1 15 5 https://www.nal.usda.gov/exhibits/speccoll/files/original/767228c1f655a4baeafc4aebd478867c.pdf ca6670a2aa1f2bbab2ae204cee969125 PDF Text Text Item D Number °2211 Silkworth, Jay CorporatB Author Division of Laboratories and Research, New York State RBDOrt/ArtlGlB TltlB Acute Toxicity In Guinea Pigs and Rabbits of Soot From a Polychlorinated Biphenyl-Containing Transformer Fire Journal/Book Title Year 000 ° Month/Day Color Number of ImaflBS D 33 Descrlpton Notes Thursday, September 20, 2001 Page 2211 of 2293 �ACUTE TOXICITY IN GUINEA PIGS AND RABBITS OF SOOT FROM A POLYCHLORINATED BIPHENYL-CONTAINING TRANSFORMER FIRE Jay Silkworth, Donald McMartin, Anthony DeCaprio, Robert Rej, Surendra Kumar and Laurence Kaminsky Division of Laboratories and Research New York State Department of Health Albany, New York 12201 �Acute Toxicity in Guinea Pigs and Rabbits of Soot from a Polychlorinated 'Biphenyl-Containing Transformer Fire. Silkworth, J.B., McMartin, D.M., DeCaprio, A.P., Rej, R., Kumar, S., and Kaminsky, L.S. (1982). Toxicol. Appl. Pharmacol. 00,00-00. A fire involving a pblychlorinated biphenyl (PCB)-containing transformer extensively contaminated the State Office Building in. Binghamton, New York with a soot-like material containing 1 ppm 2,3,7,8-tetrachlorodibenzo-p-dioxin, 50 ppm 2,3,7,8tetrachlorodibenzofuran and high concentrations of numerous other polychlorinated dibenzodioxins, dibenzofurans, and PCBs. The oral LD50 values of the soot and of its benzene extract in female guinea pigs in 0.75% aqueous methyl cellulose were 410 mg soot/kg and 327 mg soot equivalent/kg, respectively. Soot (dose range 1- 500 rag/kg) decreased WBC counts, platelet counts, and percent neutrophils, and increased percent lymphocytes in females at 100 mg/kg. Serum triglycerides were elevated in males at 100 and 500 mg/kg and in females at 500 mg/kg. Alkaline phosphatase andY~ glutamyl transferase were lowered in females at 500 and 100 mg/kg, respectively. Histopathology revealed dose-related goblet cell hyperplasia of the pancreatic duct and salivary gland duct metaplasia in males. at 500 mg soot/kg. Body weight loss was observed in both sexes Thymus weight decreased in both sexes at 100 and 500 mg/kg, and kidney weights decreased in males at 100 and 500 mg/kg. Dermal application of soot to rabbits for 24 hr caused no overt toxicity, although hepatic centrilobular hypertrophy was observed in both sexes. Similar application of soot extract caused a local serous inflammation in addition to hepatic �centrilobular hypertrophy. The oral LDSOs for 2,3,7,8-TCDD in guinea pigs in aqueous methyl cellulose or corn oil were 19 and 2.5 Vg/kg, respectively. It was concluded that the soot matrix alters dermal but not oral toxicity of its components, that the toxic effects were consistent with those reported following exposure to dibenzodioxins and dibenzofurans, and that the aqueous vehicle markedly diminished the acute toxicity of 2,3,7,8-TCDD relative to that in corn oil vehicle. �On February 5, 1981, a transformer was involved in a fire at the State Office Building in Binghamton, New York. The transformer contained a dielectric fluid (Pyranol) which was composed of the polychlorinated biphenyl (PCB) mixture, Aroclor 1254 (65%) and chlorinated benzenes (35%) together with some trace additives. The fire resulted in extensive contamination of the building with a soot-like material. .- Chemical analysis of two soot samples collected in the stairwells of the 3rd and 4th floors of the building indicated that the highly toxic compounds 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF) were present at concentrations of 2.9, 2.8 and 273, 124 ppm respectively (Smith et al., 1981a). Based on PCB pyrolysis experiments which indicate the relative contribution of 2,3,7,8-TCDF to the total polychlorinated dibenzofurans (Buser etjal., 1978) it was estimated that the soot possibly contained approximately 0.5% polychlorinated dibenzofurans. Both 2,3,7,8-TCDF and 2,3,7,8-TCDD are highly toxic compounds and their toxicity has recently been reviewed (Huff et a1., 1980). 2,3,7,8-TCDD is lethal at very low concentrations in certain species (oral LD50 in guinea pigs is 2 ng/kg, in mice 284 vg/kg). Other effects observed include thymus involution, spleen weight reduction, bone marrow hypoplasia, liver megalocytosis, bile duct hyperplasia, testicular degenerabion, renal pelvis hyperplasia, adrenal cortical atrophy, hemorrhage and cutaneous lesions. The most commonly observed dermal effect of both com- pounds in primates is the formation of acneform lesions. Both �compounds produce general debilitation and wasting. 2,3,7,8-TCDD is also a potent teratogen in mice and a carcinogen in rats. Environmental disasters in Italy and Japan have resulted in human exposures to both 2,3,7,8-TCDD and 2,3,7,8-TCDF and have provided some insight into the human toxicity of these compounds (see references in Huff et al., 1980). In many environmental contamination accidents the identification and quantitation of the individual compounds of known toxicity may be sufficient to permit risk assessments of human exposure to be made. However, because of the complexity of the contamination of these soot samples, additional animal toxicology studies with the soot were essential for such assessments to be accurate. Since the soot contains many PCB, dibenzodioxin and dibenzofuran and biphenylene isomers and congeners in addition to unknown components, the potential for synergistic or inhibitory interactions of the toxicity of any component by one or many of the other components is unknown. Also, the binding affinity for the various chemicals to the soot matrix is probably variable and is unknown. It is possible that soot particles could be excreted after ingestion without releasing the tightly bound toxic materials which would substantially diminish the toxicity. It has been demonstrated, for example, that activated carbon, when administered with 2,3,7,8-TCDD, almost completely prevented the uptake of the dioxin by rats (Poiger and Schlatter, 1980). On the other hand, chemical extraction procedures may not remove all of the toxic compounds from the soot matrix. This would result in a low estimate of the total toxicity of the chemicals present 5 �in the soot. Animal toxicity studies of the crude soot will not resolve all of these questions but should provide a clear indication of the overall toxicity of the soot taking these factors into account. There are two major aspects of potential human exposure to the soot and its components: acute exposure of personnel during clean-up operations and chronic exposure during any subsequent . - occupation of the building. The potential pathways of human exposure to the soot, in both cases, are dermal absorption, ingestion or inhalation of soot particles and volatilized components. Only acute oral and dermal exposures were addressed in the present study. The results provided information on such exposure and provided a basis for dosing during any subsequent subchronic and chronic studies. In view of the complex mixture of xeno- biotics present, the soot was treated as a single entity for the purposes of the study. Acute oral exposure was tested in guinea pigs, a species known to be sensitive to 2,3,7,8-TCDF (Moore et al., 1979), probably the most hazardous toxic component of the soot because of the relatively large quantities present. To model the poten- tial human exposure by ingestion, the soot was administered as a powder suspended in an aqueous vehicle containing 0.75% methyl cellulose to facilitate administration. A similar system has recently been demonstrated to be a safe vehicle in toxicological studies (Fritz and Becker, 1981). Acute dermal exposure was tested with rabbits which are susceptible to dermal lesions following direct exposure to polychlorinated dibenzodioxins (Huff �et al., 1980). The potential of the soot matrix to diminish bioavailability of the xenobiotics was also investigated by comparing the toxicity of the soot itself to that of a benzene extract of the soot. METHODS Male and female New Zealand White rabbits (3.5 kg) were used (H.A.R.E., Hewitt, NJ). Male and female Hartley guinea pigs (500-600 g) were obtained from a colony maintained in this Division. All animals were acclimated on arrival to a 12-hr light cycle for at least a week. Room temperature was maintained at 22-24°C, and relative humidity at 40-60%. Guinea pigs were housed two per standard rat cage and were identified by individual body markings. They were fed Certified Guinea Pig Chow 5026 (Purina, St. Louis, MO) and tap water ad libitum. Rabbits were housed one per standard rabbit cage and were fed Certified Rabbit Chow No. 5322 (Purina, St. Louis, MO) and tap water ad. libitum. Contaminated soot was collected from the stairwells of the 3rd and 4th floors of the State Office Building in Binghamton, New York with a vacuum cleaner fitted with clean collection bags. It was then sieved through #40 wire mesh to remove gross inert contamination. An extract of 5.39 g of the soot was prepared by Soxhlet extraction with benzene for 16 hr and the volume of benzene was reduced to 5 ml by heating the solution. 2,3,7,8- TCDD was obtained from the Dow Chemical Co. (Midland, MI) as a solution in toluene. The soot was analyzed as previously repor- ted (Smith et al., 1981b). �Several investigations were performed and are described individually, a) Acute Oral Toxicity of Soot in Guinea Pigs: The soot was suspended in aqueous 0.75% methyl cellulose and administered by gavage to groups of 6 male and 6 female guinea pigs at doses of 1, 10, .100 or 500 mg soot/kg body weight in volumes of 0.5 ml/100 g body weight. Lower doses of soot were administered in a single dose and the top dose was administered in three aliquots at approximately 1-hr intervals. fasted overnight prior to dosing. Animals were Control groups received either 0.5 ml aqueous methyl cellulose/100 g, 500 mg activated carbon/kg in 0.5 ml methyl cellulose/100 g or were untreated. All animals were observed daily for overt toxicity and behavioral alterations. Body weights were recorded 5 days per week and food consumption was monitored weekly. All animals, which survived the 42 day observation period were anesthetized with an overdose of carbon dioxide, exsanguinated and necropsied. At necropsy major organ's were weighed and 32 organs and tissues from each animal were fixed in 10% neutral buffered formalin. Tissues were processed by standard paraffin embedding and sections were stained with hematoxylin and eosin. Hematocrit, hemo- globin, RBC and WBC count and differential cell counts were determined. Serum was collected and analyzed for aspartate aminotransferase, alanine aminotransferase, Y~§lutamyl transferase, alkaline phosphatase, lactate dehydrogenase, and triglycerides. �b) LD50 of Soot and Soot Extract in Guinea Pigs: . Female guinea pigs in groups of six were administered a single oral dose of soot of 250, 500, 750, 1000 or 1250 mg/kg suspended in 0.75% aqueous methyl cellulose, or a benzene extract of the soot at doses equivalent to 4, 20, 100, 500 or 1000 mg soot/kg suspended in the same vehicle. In the latter case the benzene concentration was adjusted to 18% at all dose levels including the methyl cellulose control. was 0.5 ml/100 g. The volume of all doses The extract doses were administered in a single aliquot while the soot doses were administered in two to four aliquots over a maximum period of 6 hr. A soot control group received 1250 mg activated carbon/kg in the aqueous vehicle. • Body weights were determined three times weekly and animals were observed daily. All animals which survived the 42 day observation period were sacrificed. LD50 values were calcu- lated using a modification of the method of Bliss (Carmines et al., 1980). c) LD50 of 2,3,7,8-TCDD in Guinea Pigs: Female guinea pigs in groups of six were administered 2,3,7,8-TCDD by a single gavage administration at doses of 0.1, 0.5, 2.5, 12.5 and 20 Vg/kg as a solution in corn oil (0.5 ml/100 Vg) or in suspension in 0.75% aqueous methyl cellulose (0.5 ml/100 vg). Body weights were determined twice weekly and animals were observed daily. All surviving animals were killed on day 42 of exposure. d) Dermal Exposure of Soot and Soot Extract to Rabbits: The effect of dermal exposure to soot was determined by 2 applying 500 mg soot/kg to 64.5 cm of the shaved, unabraded, �dorsal surface of three male and three female New Zealand White rabbits for a 24 hr period. Active carbon, 500 mg/kg, was applied to one male and one female rabbit as controls. The soot and carbon were moistened with sterile saline and held in place with large adhesive bandages for 24 hr after which the patch was removed and the area washed free of loose soot or carbon particles. Disk collars prevented ingestion of soot and were left on until there were no visible traces of soot (14 days). The relative dermal toxicity of the extractable components of the soot was determined by spreading an extract of the soot in benzene at a dose equivalent to 500 mg soot/kg over a 64.5 area of dorsal skin of one male and one female rabbit. was protected as described above. cm 2 The area Benzene was applied to one male and one female rabbit as controls. observed daily and weighed twice weekly. All rabbits were All rabbits were sacri- ficed on day 67 using carbon dioxide and were examined for gross pathology. Liver, thymus, kidney and samples of skin from ex- posed and non-exposed areas were saved for histopathology. 10 �RESULTS - a) Acute Oral Toxicity of Soot in Guinea Pigs: Male and female guinea pigs, were necropsied 42 days after a single oral administration of Binghamton soot in 0.75% aqueous methyl cellulose. At doses of 1 and 10 mg soot/kg there was no consistent significant dose-related alteration from control values in body weight gain, liver, spleen, kidney, thymus or adrenal weights, hematology values or serum chemistry values (Fig. la,b, Tables 1-3). However, significant changes were observed in groups which received 100 and 500 mg soot/kg. Thirty-three percent mortality was recorded in the females administered 500 mg/kg (Fig. Ib). Decreased weight gain occurred in both sexes at 100 mg/kg and the body weights of both sexes at 500 mg/kg were significantly below control values (Fig. la,b, Table 1). The absolute thymus weight and the thymus weight relative to brain weight were significantly diminished from the control values in males at the 500 mg soot/kg dose and showed dose-related decrease in females administered 100 and 5jQG mg soot/kg. The absolute and relative kidney weights were decreased in a dose-related manner in males administered 100 and 500 mg soot/kg. The combined adrenal weights were significantly reduced only in males administered 100 mg soot/kg (Table 1). Hematology values from male and female guinea pigs administered either 1, 10 or 500 mg'. soot/kg in addition to males administered 100 mg soot/kg were unaltered from control values (Table 2). However the 100 mg soot/kg dose in females resulted in significant decrease in the WBC count, platelet count and the percent of neutrophils in whole blood and an increase in the 11 �percent of lymphocytes in whole blood. Serum chemistry values are shown in Table 3. There were no significant alterations from control values in male guinea pigs administered 1, 10, 100 or 500 mg soot/kg in aspartate aminotransferase, -y^lutamyl transferase, alanine aminotransferase, alkaline phosphatase or lactate dehydrogenase. However, trigly- cerides were significantly elevated in a dose-related manner in the 100 and 500 mg soot/kg groups. Female guinea pigs showed a dose-related elevation in serum aspartate aminotransferase at 100 and 500 mg soot/kg, a decrease in y-glutamyl transferase at 500 mg soot/kg, a decrease in serum alkaline phosphatase at 100 mg soot/kg and an increase in serum triglycerides at 500 mg soot/kg. Histologic examination of 32 tissues from both sexes of control guinea pigs or guinea pigs administered either 1, 10, 100 or 500 mg Binghamton soot/kg indicated that the soot affected only the pancreas and salivary gland in a clearly dose-related manner and that the observed microscopic lesions occurred only in the males (Tables 4a,b,c). Goblet cell hyperplasia of pancreatic interlobular ducts was observed in all males administered 500 mg soot/kg and in one of the six males administered 100 mg soot/kg. Normal duct epithelium was replaced by a single layer made up primarily of mucin-secreting cells which resulted in an epithelium of twice normal thickness. Metaplasia of salivary gland interlobular duct epithelium was observed in 3 of 6 males administered 500 mg soot/kg. The epithelium was thickened by pro- liferating epithelial cells which appeared similar to those pre- 12 �sent in the stratum spinosum of skin. Goblet cells/ which are present in normal columnar epithelium of the duct, were present in the superficial layer of many of these thickenings. There were no lesions in any animals which indicated cause of death. Fatty infiltration of the liver was present in two animals administered 500 mg soot/kg. These large cytoplasmic vacuoles were located centrilobularly in one male and periportally in one female. Microscopic lesions which occurred in many control and treatment groups and showed a tendency to be more frequent and/or severe in treatment groups included bile duct hyperplasia, hepatocellular cytoplasmic inclusions, vacuolation of the adrenal cortex and focal lacrimal adenitis (Tables 4a,b,c). Bile duct hyperplasia was observed in 3 of 4 control groups and in all treatment groups. A grade of -H was assigned to livers with one to a few foci of bile ducts per 25 x microscopic field proliferating 100-200 ym outward from the portal area. Fibroplasia was present in some of these foci. A grade of +2 represented 5-15 areas similar to or larger than those graded -i-1. Lesions graded -J-2 were observed in females administered 10 and 100 mg soot/kg and males administered 500 mg soot/kg. Hyaline eosinsophilic spheres and rings were found in hepatocellular cytoplasm of animals from every control and treatment group. Vacuolation of adrenal cortical cells was present only in female guinea pigs. Cytoplasmic vacuoles ranged in size from that equal to the nucleus to nearly that of the total cytoplasmic area. The size and shape of the vacuoles were compatible with having been lipid filled. A grade o£ -fl was assigned to those 13 �adrenals in which about 11-30% of the cortical cells contained vacuoles. A grade of +2 was assigned to adrenals in which about 31-50% of cortical cells contained vacuoles. Only one female guinea pig from the 500 mg soot/kg received a +2 grade. Focal inflammation of the lacriiual gland was observed in every male control and treatment group but only in one female administered 500 mg soot/kg. Lacrimal glands graded +1 contained a few foci containing lymphocytes and a few neutrophils located in and around acini. Degeneration of a few acinar cells was indicated by nuclear pyknosis, karyorrhexis and cytoplasmic vacuolation. The most severe (+2) lesion was found in one male administered 500 mg soot/kg in which 10-50% of the gland was involved. Microscopic lesions for which there were no indications of a relationship to treatment were observed in both sexes in both control and treatment groups. These lesions included hepatic focal coagulative necrosis, hepatic mononuclear cell foci/ focal interstitial nephritis and renal mineral foci. Focal coagulative necrosis of hepatocytes occupied areas from less than 0.2 mm to over 1 cm in diameter. Inflammatory reactions were absent from early lesions but later lesions possessed a basophilic rim of Kupfer cells and other macrophages, a few lymphocytes, degenerating hepatocytes and fibroplasia. Proliferating bile ducts were also present in the rim when necrotic tissue was adjacent to a portal area. A few small (100-150 ym diameter) foci of lymphocytes and a few macrophages were-observed in many livers and were not associated with degenerative 14 �changes of liver tissue. Focal interstitial nephritis consisted of one to several foci of inflammatory cells, primarily lymphocytes and a few neutrophils, located between and occasionally in cortical tubules. A few cortical tubule cells were undergoing degenerative changes as indicated by nuclear pyknosis and karyorrhexis. Many kidneys also contained one to a few mineral foci beneath the pelvic epithelium or in the adjacent renal pelvis. These foci, which measured about 0.2 mm, were often surrounded by a fibrous capsule. b) LD50 of Soot and Soot Extract in Guinea Pigs: A single oral dose of either 250 or 500 mg soot/kg to female guinea pigs resulted in a less than normal rate of weight gain after an initial 10-day period of weight loss of 12 and 15%, respectively, of starting weights (Figure Ic). Deaths occurred as early as day 12 and as late as day 42 in these groups. Doses of 750, 1000 or 1250 mg soot/kg produced losses of 27, 37 and 34%, respectively, of initial body weight during the study. Deaths occurred as early as day 9 and all animals in each of these dose groups were dead by day 27. The 42 day LD50 for soot was calculated to be 410 mg soot/kg (Carmines et al., 1980). ^ Female guinea pigs administered an extract of the soot equivalent to 4 mg soot/kg gained weight at the control rate during the entire observation period (Figure Id). Doses of either 20 or 100 mg soot equivalent extract/kg resulted in slower rate of weight gain than in controls although there were no deaths at these doses. Animals administered either 500 or 1000 15 �mg soot equivalent extract lost up to 31 or 36%, respectively, of their initial body weight during the study. The cumulative mortality was 80% and 100%, respectively, in the 500 and 1000 mg soot equivalent/kg groups. Deaths occurred as early as day 7 and as late as day 21 and were preceded by gradual weight loss. The 42 day LD50 of the soot extract was calculated to be equivalent to 327 mg soot/kg, c) LD50 of 2,3,7,8-TCDD in Guinea Pigs: Female guinea pigs administered a single dose of either 0.1 or 0.5 yg 2,3,7,8-TCDD/kg in corn oil gained weight at the control rate (Figure le). Animals administered 2.5 yg 2,3,7,8- TCDD/kg gained weight at a lower rate than controls after an initial weight loss of 7%. Deaths were not observed until day 32 and by the end of the 42 day observation period the cumulative mortality was 50%. Groups administered either 12.5 or 20.0yg 2,3,7,8-TCDD/kg lost 34 and 33%, respectively, of their initial body weight and had reached 100% cumulative mortality by days 16 and 9 respectively. The 42 day LD50 of 2,3,7,8-TCDD in corn oil was calculated to be 2.5 yg/kg. Female guinea pigs administered either 0.1, 0.5, 2.5 or 12.5 2,3,7,8-TCDD/kg in 0.75% methyl cellulose gained weight at the same rate as controls. .However, animals administered 20.0 yg \ 2,3,7,8-TCDD/kg in methyl cellulose lost up to 15% of their initial body weight by day 12. The first death in this group occurred on day 12 and the cumulative mortality reached 67% by day 42. The 42 day LD50 of 2,3,7,8-TCDD in methyl cellulose was calculated to be 19 yg/kg. 16 �d) Dermal Exposure of Soot and Soot Extract to Rabbits: Rabbits dermally exposed to soot for a 24 hr period exhi- bited no signs of overt toxicity or weight loss during the 65 day observation period. Histologic examination of thymus, kidney and skin from exposed and unexposed areas showed no lesions. How- ever, hypertrophy of centrilobular hepatocytes involving 25-75% of the hepatic lobule was observed in 2 of the 3 exposed males .. . and 1 of the 3 exposed females. Large round vacuoles, indicative of fatty infiltration, were also observed in approximately 25% of the hepatocytes of the female with centrilobular hepatocyte hypertrophy. Rabbits exposed to active carbon were in excellent condition throughout the study and were histologically normal. The male and female rabbits which received a single dermal application of an extract of the soot equivalent to 500 mg soot/kg each developed a mild inflammatory reaction at the application site which first appeared on day 4 (Figure 2). The lesion developed into a serous inflammatory reaction of moderate intensity and 2-3 mm in thickness. The reaction reached and main- tained its maximum severity during days 14-34 after application. Complete healing had occurred by day 41. Microscopic evaluation of skin taken from the reaction site on day 67 appeared similar to control tissues. Thymus and kidney tissue from the male and the female rabbits exposed to the extract were normal. However, although the liver from the male appeared normal, centrilobular hypertrophy which involved 51-75% of the hepatic lobule was observed in the female. There was no weight loss in animals exposed to the soot extract. Control animals which received a dermal application of benzene were in excellent condition 17 �throughout the observation period and were histologically normal. DISCUSSION The results of these studies have provided a basis for the assessment of the acute toxicity of the Binghamton soot by relating its toxicity to that of the known components of the soot and by addressing the question of the bioavailability of its toxic components. Chemical analysis of the soot sample used in these studies indicated a composition of approximately 1 ppm 2,3,7,8-TCDD, 50 ppm 2,3,7,8-TCDF and 0.5% PCBs in addition to many chlorinated dibenzodioxin and dibenzofuran congeners. However, the carbon- like matrix of the soot presented the possibility that the toxic components of the soot may be tightly bound, and may prevent absorption and result in an observed toxicity lower than expected. This concept is supported by previous reports that a charcoal matrix almost completely prevented absorption of 2,3,7,8-TCDD (Poiger and Schlatler, 1980). The toxicological findings of this study, in which guinea pigs were administered a single oral dose of soot, included mortality, decreased weight gain, immediate and precipitous weight loss after which there were no cases of survival, thymic atrophy, decreases in kidney and adrenal weights, decreased platelet and WBC counts and an increase in serum aspartate aminotransferase. Pathology findings indicated that glandular and duct epithelium were primary target tissues. These findings are consistent with the findings of McConnell et al. (1978) in which guinea pigs were administered 18 �various purified chlorinated dibenzo-p-dioxin congeners, and with the findings of Moore et . l . (1979) in which guinea pigs were a. administered 2,3,7,8.-TCDF and indicate that the soot toxicity is due to its chlorinated dibenzo components. The oral LDSOs of the soot and an extract of the soot, 410 mg soot/kg and 327 mg soot equivalent/kg, respectively, indicate 4 that the carbon-like matrix has only a minimal role in decreasing soot toxicity. The method used for extraction of the soot has been demonstrated to be the most effective in the extraction of chlorinated dibenzodioxins and dibenzofurans from fly ash (Kooke et al., 1981). However, our dermal studies with rabbits, although the numbers of animals were not large enough for statistical comparisons, indicated that the soot matrix prevented a local inflammatory reaction even though enough absorption occurred to produce liver pathology similar to that produced in rabbits exposed to the extract. The contrasting absence of hepatocellular hyper- trophy in our guinea pigs exposed to either soot or soot extract represents a species difference in the toxic response. The aqueous vehicle used in the study with guinea pigs was chosen because it is toxicologically innocuous (Fritz and Becker, 1981), provides a stable suspension of the soot thus facilitating homogenous dosing, and is more likely to model potential human oral exposure than would an oil based vehicle. However, pre- viously reported acute toxicities of 2,3,7,8-TCDD and 2,3,7,8TCDF (see Huff et al., 1980; McConnell _et al., 1978) have used oil vehicles. Therefore, to compare soot toxicity with chlori- nated dibenzodioxin and dibenzofuran toxicities, an assessment oE 19 �the role of the vehicle was necessary. Our data with 2,3,7,8- TCDD (LD50 = 19 yg/kg) indicate that the aqueous vehicle diminishes acute oral toxicity in guinea pigs by a factor of approximately 8 relative to that in corn oil (LD50 = 2.5 pg/kg)« If similar factors apply to other chlorinated dibenzodioxins and dibenzofvirans, an acute oral exposure to the soot in an aqueous vehicle would be less hazardous than in an oil vehicle. The oral \ LD50 of 2,3,7,8-TCDD in corn oil in our study was consistent with the literature value (Huff et al., 1980). Based on the chemical analyses of the soot (Smith et al., 1981b), the LD50 dose of soot administered to the guinea pigs contained approximately 0.4pg 2,3,7,8-TCDD/kg and 21 y g 2,3,7,8TCDF/kg. Therefore, since the LD50 of 2,3,7,8-TCDD in the aqueous vehicle is 19 yg/kg, the lethal effects of the soot did not arise from the 2,3,7,8-TCDD but rather from the 2,3,7,8-TCDF and/or other pollutants. Two analyses of a sample of soot which differed from that used in this study, but which was collected from the same building, revealed relatively high quantities of a wide variety of other chlorinated dibenzodioxins and dibenzofurans (Stalling, 1981; Rappe, 1981). The LD50 of 2,3,7,8-TCDF in guinea pigs has been reported to be 5-10 yg/^3 (Huff et al., 1980). If it is assumed that the acute toxicity of 2,3,7,8-TCDF is also diminished by a factor of 8 when administered in aqueous vehicle then a major fraction of toxicity of the soot must arise from components other than the 2,3,7,8- chlorinated compounds. In summary, our findings indicate that: the soot matrix does not significantly alter the oral toxicity of the soot but 20 �does influence its dermal toxicity; the toxic effects produced by the soot are consistent with previously reported effects produced by dibenzodioxins and dibenzofurans in guinea pigs; the amounts of 2,3,7,8-TCDD and 2,3,7,8-TCDF in the soot are, alone, insufficient to account for the observed toxicity and therefore other dibenzodioxins, dibenzofurans and/or other contaminants are involved; and the aqueous vehicle used in these studies diminished 2,3,7,8-TCDD toxicity. 21 �REFERENCES Buser, H.R., Bosshart, H.P., and Rappe, C. (1978). Formation of polychlorinated dibenzofurans from the pyrolysis of PCBs. Chemosphere 7, 109. Carmines, E.L., Carchman, R.A., and Borzelleca, J.F. (1980). A method for the evaluation of dose-effect data utilizing a programmable calculator. J. Environ. Pathol. Toxicol. 4, 23-30. , Fritz, H., and Becker, H. (1981). The suitability of carboxymethylcellulose as a vehicle in reproductive studies. Arzn. - Fors. Drug Res. 31, 813-815. Huff, J.E., Moore, J.A., Saracci, R,, and Tomatis, L. (1980). Long term hazards of polychlorinated dibenzodioxins and polychlorinated dibenzofurans. Environ. Health Perspect. 36, 221-240. Kooke, R.M.M., Lustenhouwer, J.W.A., Olie, K., and Hutzinger, 0. (1981). Extraction efficiencies of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans from fly ash. Anal. Chem. 53, 461-463. McConnell, E.E., Moore, J.A., Haseman, J.K., and Harris, M.W. (1978). The comparative toxicity of chlorinated dibenzo-p-dioxins in mice and guinea pigs. Toxicql. Apgl. Pharmacol. 44, 335-356. Moore, J.A., McConnell, E.E., Dalgard, D.W., and Harris, M.W. (1979). Comparative toxicity of three halogenated dibenzofurans in guinea pigs, mice and rhesus monkeys. New York Acad. Sci. 320, 151-163. Poiger, 'H., and Schlatter, C.H. (1980). Influence of solvents and absorbents on dermal and intestinal absorption of TCDD. Fd. Cosmet. Toxicgl. 18, 477-481. Rappe, C. (1981). Report on the analysis of Binghamton soot. Report University of Umea, Sweden. Smith, R.M., O'Keefe, P.W., Hilker, D.L., Jelus-Tyror, B.L., and Aldous, K. (1981a). Chemical analysis of 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlordibenzofuran in a soot sample from the transformer explosion in Binghamton, New York. N.Y. State Department of Health Report. February 20, 1981. 22 �Smith, R.M., Hilker, D.L., O'Keefe, P.M., Kumar, S., O'Brien, J., Jelus-Tyror, B.L., and Aldous, K. (1981b). Analysis of a Binghamton soot sample for tetrachlorodibenzofurans and tetrachlorodibenzop-dioxins. N.Y. State Department of Health Report. October 1, 19.81. Stalling, D. (1981). Chlorinated dibenzofurans and related compounds in soot formed in a transformer fire, in Binghamton, NY. Preliminary Report, Columbia National Fisheries Research Laboratory,' U.S. Fish and Wildlife Service. 23 �TABLE 1 BODY AND ORGAN WEIGHTS FROM GUINEA PIGS 6 WEEKS AFTER A SINGLE ORAL ADMINISTRATION OF BINGHAMTON SOOT IN 0.75% METHYL CELLULOSE* Controls Sex Untreated Vehicle Active Car bonk Binghamton Soot ng/kR 500 ing/ kg Parameter 1 10 100 500 723+15 655±33 732+17 692+44 739±24 698425 737+21 667+24 649+34 641+12 522±40e 570+29C M F +202 +213 +196 +115 +200 +126 +186 +78 +100 +45 -3 -31 Brain Wt(g) M F 3.75±0.05 3.72±0.08 3.87±0.050 3.75+0.04 3.91+0.12 3.79+0.12 3.75±0.06 3.9340.18 3.65±0.05C 3.68±0.03 3.7440.08 3.61+0.06 Liver Wt(g) M 31.0041.60 36.00+3.31 29.63+1.65 30.60+3.76 32.01+3.43 30.13+3.21 34.61+1.65 34.01+3.80 30.0842,48 28.1241.86 27,85+2.24 22.71+0.41 Liver Wt/ Brain Wt (%) M F 8.28+0.41 9.75+0.97 7.67+0.35 8.17±1.02 8.2440.94 7.91+0.63 9.22+0.38 8.68+0.96 8.29+0.79 7.64±0.52 7.42+0.50 6.296+0.06 Spleen Wt (g) M p 0.58040.025° 0.628±0.043 0.758+0.061 0.74940.108 0.688+0.027 0.941+0.066 0.726+0.050 1.12040.103° 0.650+0.034 1.016+0.073 0.853+0.084 0.818+0.107 Spleen Wt/ Brain Wt (2) M F 0. 15540. 007C 0.17040.012 0.196+0.015 0.20+0.03 0.176+0.007 0.285+0.030 0.19440.014 0.28440.019° 0.17940.011 0.276+0.020 0.227+0.020 0.227+0.030 Body Wt (S) M Body Wt Change During Study (g) F :1 b Data expressed as mean +_ standard error, n »• 4-6 per group. Active carbon in 0.75% aqueous methyl cellulose served as the control group for statistical evaluation using the Student's t-test. c p^O.05 p<0.02 p^O.Ol p^O.OOl d c f �TABLE I (Cont'd) BODY AND ORGAN WEIGHTS FROM GUINEA. PIGS 6 WEEKS AFTER A SINGLE ORAL ADMINISTRATION OF BINGHAMTON SOOT IN 0.75Z METHYL CELLULOSE* Controls Sex Untreated Vehicle Active Carbon'* Binghamton Soot mg/kfi 500 mg/kg Parameter 1 10 100 500 Thyr.us Wt (8) M F 0.527+0.029 0.433±0.034 0.598±0.122 0.711+0.058 0.431+0.033 0.693+0.064 0.457+0.014 0.584±0.058 0.327+0.028 0.527+0.015° 0. 250+0. 038C . 0. 368+0. 018f Thymus Wt/ Brain We (%) M F 0.141*0.009 0.117±0.009 0.154*0.030 0.190*0.02 0.112*0.009 0.183*0.013 0.122*0.003 0.151*0.018 0.090*0.009 0.143*0.004° 0. 066*0. 010C 0. 102*0. 006e Combined Kidney Wts (g) M 5.129*0.157 4.810±0.365 5.153+0.249 4.982+0.442 4.923*0.244 5.170*0.428 5.480+0.243 4.658+0.311 4. 218+0. 151e 4.223+0.178 3.955+0.217e 3.671+0.526 Kidney Wt/ Brain Wt (%) M. F 1.37140.049 1.296+0.096 1.334+0.053 1.330+0.120 1.267+0.077 1.363±0.090 1.462*0.059 1.204*0.107 1. 159*0. 05C 1.147+0.049 1. 056+0. 045e 1.018+0.015 Combined Adrenal Wts (g) M F 0.256±0.012 0.236+0.023 0.283+0.012 0.282+0.018 0.262+0.010 0.295*0.019 0.272+0.010 0.287+0.022 0.249±0.009C 0.276*0.020 0.237+0.017 0.305+0.035 Adrenal Wt/ Brain Wt M F 0.06910.004 0.064+0.006 0.074+0.004 0.075±0.005 0.099+0.033 0.078+0.008 0.073*0.002 0.074+0.008 0.068*0.002 0.075*0.005 0.063+0.005 0.084 ±0.008 F 3 Data expressed as mean + standard error, n - 4-6 per group, *° Active carbon in 0.75% aqueous methyl cellulose served as the control group for statistical evaluation using the Student's t-test. c p^O.05 PlO.OOl �TABLE 2 HEMATOLOGY VALUES FROM GUINEA PIGS 6 WEEKS AFTER A SINGLE ORAL ADMINISTRATION OF BINGHAMTON SOOT IN 0.75% METHYL CELLULOSE3 Controls Parameter Sex Untreated Vehicle Active Carbon Control" Binghamton Soot mg/kg 500 mg/kg 1 10 100 500 PCV(Z) M F 49±1 50±1 45±1 44±2 47+1 46+1 46+1 44+3 47+1 43+2 4112 4112 WBC (xlQ5/cc) M F 4.9±0.8 5.5iO,5 4.5±0.3 10+1.0 5.5+0.7 7.9+1.8 5.0+0.4 9.2+2.1 5.8+1.1 6.610.8C 4.5+0.5 7.2+1.4 RBC (x!09/cc) M F 4.2±0.3 4.8±0.2 5.110.2 5.2+0.5 5.2+0.2 . 5.5+0.2 4.810.3 4.610.2 5.3+2.5 4.910.3 4.5+0.4 5.2+0.2 Platelet (x!07/cc) M F 42+24 50±26 8±3 34+4.7 8+3 24±3.8 9+5 23+13 1114 1413.3d Lymphocytes % M F 73+6 78±2 73+4 64+6 67+7 65+6 65+1 73+6 7215 80+2C 71+3 66+11 Neutrophils % M F 26+6 21±2 2614 34±6 31+8 34+6 35+2 2315 28+5 2012C . 27+4 33+11 Eosinophils % M F 0.6±0.2 0.7±0.5 0.3+0.2 2.5+0.6 1.0+0.7 2.3+0.8 0.210.2 4. 6+1. -9 0.5+0.2 0.810.3 0.7+0.4 1.4+0.4 Monocytes M F 0.3±0.2 0.5±0.2 0.3+0.2 0.5+0.3 0.8+0.5 0.8+0.2 0.510.3 0.3+0.2 0.3+0.2 0.3+0.2 0.7+0.2 0.8+0.2 . 1817 23+9.5 • a b c Data expressed as mean + standard error, n = 4-6 per group. Active carbon in 0.75% aqueous methyl cellulose served as the control group for statistical evaluation using the Student's t-test. o<0.001 �TABLE 3 SERUM CHEMISTRY VALUES FROM GUINEA PIGS 6'WEEKS AFTER A SINGLE ORAL ADMINISTRATION OF BINGHAMTON SOOT IN 0.751; METHYL CELLULOSlf Controls t Parameter Sex Untreated Vehicle Active Carbon11 Binghamton Soot ng/kg 500 mg/kg Aspartate M AT.-! notr.-ir.r; ferase F (v;M/nd.n/L) '11.6+4.8 •y-Glutamyl '!'rar!::rcr,-tr:r(ljM/min/L) 12.411.1 H p 68.8+11 14.8+2.1 1 10 53.2+5.4 37.313.1 46.7+6.0 44.218.1 53.8111.6 5319 13.111.0 19.0+1.7 .13.511.6 18.0+1.1 500 100 60.6+11.6 51.513. 5^ 44.513.0 60.019.3° 14.110.7 13.810.9 13.5+0.7 13.9+1.5 10.9+1.3 11.711.0e *t Alan in e K .'ur:inotran:;rernse F (UVsdn/L) 29.7+1.0 25.3+2.1 35.314.6 23.2+1.5 30.713.1 24.5+2.0 35.5+3.1 24.6±2.2 27.0+1. 8 23+2 2613 20+2 Alkaline Phosphatase (uM/mirt/L) M F 160112 163120 126120 126121 123+13 93112 155+8 77+7 107+6 7217C 11119 85113 ' •iC't.ttte Dohyclrogenase M F 590+33 562+17 567148 600+38 741199 638+65 620+87 571137 486+62 567+87 476+98 539+30 M 101122 138+24 87+5 101+17 113+39 114+28 114+32 77121 166+34° 120+29 282+38^ 168+10" (yM/nin/D Triglycericies Ong/dL) Jjata expressed as mean + standard error, n = 4-6 per group. Active carbon in 0.757. aqueous methyl cellulose served as the control group for statistical evaluation using the Student's t-test. C , p<0.05 d ^ ^ 0, 7 l ' P<"0.05 a p<_0.001 �TABLE MICROSCOPIC LESIONS IN CONTROL GUINEA PIGS everage grade of lesion Female , Carbon + MC Z en i, ma Is with lesion ct f tissue examined •e. Z eainals vith lesion everage grade of lesion % eaimals vith lesion a 3 U) a Male, Carbonb+ MC average grade of lesion Male, MCa Male, Untreated Pancreas ;netaplasia of duct epithelium Q 6 0 0 6 0 0 6 0 0 6 0 Saiivary gland ;squareou6 mctaplaoin of duct epithelium 0 6 0 0 6 0 0 6 0 0 6 0 Liver;fatty infiltration 0 6 0 0 6 0 0 6 0 0 6 0 Liver; bile duct hyperplasia 0 6 0 2 6 33 2 6 33 3 6 50 1.0±0 Adreual;cortical vacuolation 0 6 0 0 G 0 0 6 0 3 6 50 Liicriraal gland; focal adenitis 3 6 50 3 6 50 1 6 17 0 6 0 Liver; focal necroaio 3 6 50 3 6 50 4 6 67 1 6 17 Livcr;mononuclear cell foci 1 6 17 5 6 67 2 6 33 3 6 50 Kidney ; focal interstitial nephritis 2 6 33 5 6 83 2 6 33 4 6 67 Kidney jmineral foci 2 6 33 1 6 17 2 6 33 0 6 0 g VI o> •a u u •g <B 1 8 o 3 ia (a •ri O •ri ta <0 r-i U (U r-i <M O J ID 0) H « •ri It in r-i a H -a a oo o) to 8 w HI •ri "0 41 U S U) m •ri 0) Lesion a b 0.75% sicthyl cellulose, 0.5 ml/100 g body Active carbon, 500 og/kg body weight 0 1 1.040 1 o to •ri O r-4 0) 3 •o OJ <u u to l.OiO 1 to w 4-1 ta 1.0 ±0 �TABLE MICROSCOPIC LESIONS IN MALE GUINEA PICS. AWlNISTKKRDjnMrjIAKrOM. SOOT8.. 1 mp,/kR a o wJ 10 mR/kp, a 0 a o 1-1 ui 0} _l ^0 Q) c "i "5 •d 3 ft 01 (U >M ta a o IS 4) (-1 r-i Q) r-< o "8 « in Pancreas ;n:etaplasia of duct epithelium 3 X t! 3 ^ n) *O <!) a T * 4) in w H a DO a rt "a * a •K, Lesion a o -rt f to .H 3 "K. M oa !QO wr./kp, H la 4) f-t a 0 a -ri in O a a ^ *M (U r-t i-< a g ^t "S 1* CO U CJ CO Q *v U ^^ r-i 1 3 ^ 0) a U) •rl J3 *** ti it "S a A ff •g a t-i a to B •H •rl n to 41 ta Qt ta U 1-4 » •rj 4J a -K. a a o 4) 4) 0) *•) n vi 3 <H to W 3 U) U) 500 WE/kf r S 4) § Q a) H B) -ft. •Si M a •e. 41 4) t-i "g H V tl ta ^ ^{ UJ tH CO vt *H •S. g Tl (0 41 r-4 V-i 0 1 M 1 >«• •o O •ri U) M 3 S M CO 0) CO 0) <u ^ . 0 7 0 0 . 6 0 1 6 17 6 6 100 Salivary gland ; squamous metaplasia of duct epithelium 0 7 0 0 6 0 0 6 0 3 6. 50 Liver; fatty infiltration 0 7 0 0 6 0 0 6 0 1 6 17 1 Liver;bile duct hyperplasia 1 7 14 3 6 50 2 6 33 3 6 50 1.7±0.6 Adrenal;cortical vocuolation 0 7 0 0 6 0 0 6 0 0 6 0 Lucrical gland; focal adenitis 2 7 29 2 6 33 2 6 33 5 6 83 Liver; focal necrosis 2 7 29 4 6 67 1 6 17 2 6 33 Liver ;taonosvuclear cell foc^. 5 7 71 2 6 33 0 6 0 3 6 50 Kidney; focal interstitial nephritis 3 7 43 2 6 33 4 6 67 6 6 100 Kidney ;cdneral foci 3 7 43 2 6 33 3 6 50 3 6 50 1 1 ±0 Soot atlninistcred orally in 0.752 aqueous methyl cellulose. 1 ±0 1 ±0 1 ±0 1 ±0 1.2±0.5 �TABLE Ac a &4 •Ri «s« i « 0 s 0 o Tl n V i-l 2 * * I $ 0 U CO ani&als vrlth lesion tissue exsained a 5 <a fin i Mis vith lesioa Li aion 100 inR/k R 10 niR/kf r 1 inR/fcc . J! O ta "0 X a 0) a 14 u •rl 01 <u * : r-t <H * V) CD g <U H ti. «s« •H S 3 fr« VI 4J IU r-i 2 g A •s •g n 01 t-4 to «I a) 3 h 1 3 500 mp,/k R gs 3 ^ : * i o TI •rl tissue examined , MICROSCOPIC LESIONS IN FEMALE GUINEA PIGS, ADMINISTERED BIKGI^fTOH SOOTa to a ts m « g H TI fl lu «K» •Ki M ta a o •rl g Tl 10 0 T-i £ S u tl a a U> rH r-i <H a u ri e> a a o TI u <i) * <a o u *o S ca ft) 3 Tl •M § •ta 1 I s s« s «S« M 4> bO (a qt u u 1 g P^:'.crca3;metaplaoia of duct epithelium 0 5 0 0 6 0 0 6 0 0 5 0 Salivary gland ;squasiouG oetaplasia of •' duct epithelium 0 5 0 0 5 0 0 5 0 0 5 0 L!\'er;fa£ty infiltration 0 5 0 0 6 0 0 6 0 1 5 20 2 Liver; bile duct hyperplasia 3 5 60 1 ±0 3 G 50 6 6 100 1.5±0.7 2 5 40 1 ±0 Adrenal; cortical vacuolation 2 5 40 1 ±0 3 6 50 3 6 50 1 ±0 5 5 100 LucriMl gland; focal adenitis 0 5 0 0 6 0 0 5 0 1 5 20 Liver; focal necrosis 1 5 20 1 6 17 1 6 17 2 5 40 Liver ;rjononuclcar cell foci 3 5 60 3 6 50 3 6 50 2 5 40 Kidney; focal interstitial nephritis 4 5 eo G 6 100 5 6 83 3 5 60 Kidney ; mineral foci 2 5 40 0 6 0 2 6 33 1 5 20 i Soot administered orally in 0.75% aqueous methyl cellulose. 1.7±0.6 1 ±0 I 1 1.2+0.5 1 1 �LEGENDS Fig. 1. Body weight changes in male and female guinea pigs administered single, oral doses (Day 0) of Binghamton .soot (A-C) or soot extract (D) in 0.75% aqueous methyl cellulose, or 2,3,7,8-TCDD in either corn oil (E) or methyl cellulose (F). Asterisks indicate individual mortalities during the observation period. Fig. 2. Female rabbit 32 days after dermal application of 1.4 ml benzene extract equivalent to 500 mg Binghamton soot/kg, showing a serous inflammation at the application site. �140 DAYS �� Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Alvin L. Young Collection on Agent Orange Description An account of the resource <p style="margin-top: -1em; line-height: 1.2em;">The Alvin L. Young Collection on Agent Orange comprises 120 linear feet and spans the late 1800s to 2005; however, the bulk of the coverage is from the 1960s to the 1980s and there are many undated items. The collection was donated to Special Collections of the National Agricultural Library in 1985 by Dr. Alvin L. Young (1942- ). Dr. Young developed the collection as he conducted extensive research on the military defoliant Agent Orange. The collection is in good condition and includes letters, memoranda, books, reports, press releases, journal and newspaper clippings, field logs and notebooks, newsletters, maps, booklets and pamphlets, photographs, memorabilia, and audiotapes of an interview with Dr. Young.</p> <p>For more about this collection, <a href="/exhibits/speccoll/exhibits/show/alvin-l--young-collection-on-a">view the Agent Orange Exhibit.</a></p> Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Box The box containing the original item. 088 Folder The folder containing the original item. 2211 Series The series number of the original item. Series IV Subseries II Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Creator An entity primarily responsible for making the resource Silkworth, Jay Donald McMartin Anthony DeCaprio Robert Rej Surendra Kumar Laurence Kaminsky Description An account of the resource <strong>Corporate Author: </strong>Division of Laboratories and Research, New York State Department of Health, Albany, New York Title A name given to the resource Acute Toxicity in Guinea Pigs and Rabbits of Soot From a Polychlorinated Biphenyl-Containing Transformer Fire Subject The topic of the resource BSOB animal studies dioxin https://www.nal.usda.gov/exhibits/speccoll/files/original/f3952984a72c2245626b9dc9b1d87f74.pdf 38e9c40370894bea57b99dfbd68d8cca PDF Text Text Item ID Number °1442 Author Corporate Author ROpOrt/ArtiOlO TitlO Perspectives on the Safety of 2,4-D JOUmal/BOOk Title Comments from CAST Year ™& Mouth/Day December Color ^ Number of Images 21 Descpipton Notes Tuesday, May 15, 2001 Page 1442 of 1514 �[AST ISSN 0194-4096 PERSPECTIVES ON THE SAFETY OF 2,4-D COMMENTS from CAST 1987-3 December 1987 Council for Agricultural Science and Technology �Council for Agricultural Science and Technology (CAST) Member Societies American Academy of Veterinary and Comparative Toxicology American Association of Cereal Chemists American Dairy Science Association American Forage and Grassland Council American Meat Science Association American Meteorological Society American Peanut Research and Education Society American Phytopathological Society American Society for Horticultural Science American Society of Agricultural Engineers American Society of Agronomy American Society of Animal Science American Veterinary Medical Association Aquatic Plant Management Society Association of Official Seed Analysts Council on Soil Testing and Plant Analysis Crop Science Society of America Institute of Food Technologists North Central Weed Control Conference Northeastern Weed Science Society Plant Growth Regulator Society of America Poultry Science Association Rural Sociological Society Society of Nematologists Soil Science Society of America Southern Weed Science Society Weed Science Society of America Western Society of Weed Science COMMENTS from CAST Publications in the COMMENTS from CAST Series are official letters and other comments of broad interest, usually written by one person. Each COMMENT bears the names of the persons who prepared it, and they are responsible for the content. Through representatives on the CAST Board of Directors, the member societies are responsible for the policies and procedures followed by the headquarters office in developing, processing, and disseminating COMMENTS from CAST, and, depending on the nature of the publication, the society representatives nominate qualified persons from their respective disciplines for participation in the preparation. Aside from these involvements, the member societies have no responsibility for the content of any COMMENT. Authors of COMMENTS from CAST, other than persons in the headquarters office, serve as scientists and not as representatives of their employers. They receive no honoraria but are reimbursed upon request for travel expenses associated with the preparation. Their time is contributed by their employers. Costs of publishing and distributing the COMMENTS are borne by CAST. CAST encourages the reproduction of its publications in their entirety for independent distribution, but it has no responsibility for the use that may be made of them. CAST does not endorse either products or services; thus, a reproduction of a publication made in such a way as to imply an endorsement would be considered inappropriate. Headquarters Office 137 Lynn Avenue, Ames, Iowa 50010-7120 Telephone 515-292-2125 �PERSPECTIVES ON THE SAFETY OF 2,4-D COMMENTS from CAST 1987-3 December 1987 Council for Agricultural Science and Technology �Task Force Members Lawrence J. Fischer (Chair), Center for Environmental Toxicology, Michigan State University, East Lansing Donald E. Davis, Department of Botany, Plant Pathology and Microbiology, Auburn University, Auburn Judith Marquis, Department of Pharmacology and Experimental Therapeutics, School of Medicine, Boston University, Boston David B. Marx, Agricultural Statistical Laboratory, University of Arkansas, Fayetteville Wendell R. Mullison, Herbicide Consultant, 1412 North Parkway, Midland, Ml 48640 Gary D. Osweiler, Veterinary Diagnostic Laboratory, Iowa State University, Ames Stanley H. Schuman, Department of Family Medicine, Medical University of South Carolina, Charleston Robert D. Sweet, Department of Vegetable Crops, Cornell University, Ithaca Sheldon L. Wagner, Agricultural Chemistry Department, Oregon State University, Corvallis Robert B. Wallace, Department of Preventive Medicine, University of Iowa, Iowa City �Foreword The public faces what it may think are insurmountable obstacles in dealing with the relationship between human health and chemicals in the environment. Wide-ranging opinions exist on the benefits and risks associated with chemicals used in production agriculture, food processing, home lawn care, and other areas of daily life. Plenty of evidence exists that chemical use has benefited agriculture and the food supply through the control of pests and diseases of animals and plants. Yet consumers and producers alike are asking necessary and critical questions about the impact of these chemicals on human health. One chemical used widely to control weeds on farms, forests, lawns, and golf courses for four decades is 2,4 dichlorophenoxyacetic acid or 2,4-D. It is suspected by some to cause cancer in humans. The release of a paper by Hoar et al (1986) implicating 2,4-D in the increased incidence of non-Hodgkin's lymphoma in a group of Kansas wheat farmers led the CAST board to initiate a task force review of the 2,4-D literature. The task force, under the leadership of Dr. Lawrence J. Fischer and consisting mainly of epidemiologists, toxicologists, and weed scientists, met to review the situation, agree upon an outline for the report, and establish a writing protocol. The task force agreed to focus on epidemiology, exposure to 2,4-D by various segments of the population, and animal toxicology in the report. The resulting report, "Perspectives on the Safety of 2,4-D," addresses public concerns regarding health risks and use of the herbicide, and explains how animal toxicity studies are conducted, with specific reference to 2,4-D. On behalf of CAST, we thank the task force participants, who gave of their time and expertise to prepare this report as a contribution from the scientific community to greater public understanding of chemical issues. We thank also the employers of the participants, who made the time of their staff members available at no cost to CAST. The members of CAST deserve special recognition. Their unrestricted contributions in support of the work of CAST have financed the preparation and publication of this report. "Perspectives on the Safety of 2,4-D" is being distributed to all members of Congress; to certain members of the U.S. Department of Agriculture, the Food and Drug Administration, and the Environmental Protection Agency; to media personnel who have asked to receive CAST publications; and to institutional members of CAST. Individual members may receive a copy upon request. The report may be republished or reproduced in its entirety without permission. However, if the report is republished, credit to the authors and CAST is requested. William W. Marion Executive Vice President CAST Billy E.Caldwell President CAST �Contents SUMMARY 1 INTRODUCTION 2 EPIDEMIOLOGICSTUDIES The Nature of Epidemiology Studies of 2,4-D as a Possible Cause of Human Cancer The Kansas Study Ongoing Studies 3 3 4 4 6 HUMAN EXPOSURE TO 2,4-D Manufacturing Personnel Applicator Exposure Forestry Applicators General Public Environmental Sources of Exposure Conclusions Regarding Exposure 7 7 7 7 8 9 9 TOXICITY STUDIES IN LABORATORY ANIMALS Advantages and Limitations of Animal Studies Toxicity of 2,4-D from Single and Repeated Doses Cancer Testing Using Laboratory Animals Carcinogenicity of 2,4-D in Animal Studies 10 10 10 11 12 REFERENCES 15 �Summary All available information gained from epidemiologic studies, and from controlled experiments in laboratory animals should be used in making a judgment regarding the safety of 2,4-D. Using such an approach, this task force concludes that 2,4-D, as it is generally used, does not represent a significant human health threat. However, users should apply it with the care and respect required of every chemical that can cause harmful effects in high doses. Many chemicals enjoying wide use, such as detergents, gasoline, and certain insecticides fall into this category. A recent epidemiologic study concluded that human exposure to 2,4-D related to its use in Kansas agriculture was associated with an increased incidence of cancer. This finding should not be dismissed as wrong, nor should it be accepted as a correct reflection of the safety of 2,4-D. This study, in light of its strengths and weaknesses, must be evaluated with results from other studies, which indicate that 2,4-D use does not represent a significant cancer risk. A cautious approach dictates that reports of possible carcinogenic effects of 2,4-D in humans serve to increase our scientific vigilance and investigation into the issue. Results from several ongoing epidemiologic studies of cancer and herbicide use will be available in the near future. If those results support the findings of the study conducted in Kansas, then the government should give serious consideration to restricting the use of 2,4-D. Should the forthcoming data not indicate a link between 2,4-D exposure and human cancer, then our present conclusion will stand. �Introduction Use of the herbicide 2,4-D started about 40 years ago. It revolutionized weed control practices on farms, forests, waterways, and lawns. Users continue to apply 2,4-D to millions of acres because they find it effective. In general, they perceive it as fairly safe for themselves and the environment. Periodically, however, questions have been raised regarding the safety of 2,4-D for humans. Most recently the "Kansas Farm Worker" study indicated that high exposure to 2,4-D was associated with one particular type of cancer (Hoar et al., 1986). The results of this study, conducted by scientists at the National Cancer Institute (NCI), prompted renewed concern for the safe use of 2,4-D. An excellent, recent review of the scientific literature does exist concerning the safety of 2,4-D (Canadian Centre for Toxicology, 1987). This report will not duplicate that effort. A CAST Task Force met in June of 1987 to discuss the safety of 2,4-D and to develop a report that would benefit the informed public. The goal of this document is to place in perspective both the current and older information relevant to the safety of 2,4-D to humans. Task force members hope that unwarranted fears will be laid to rest. At the same time health risks that may be present, or that have not yet been studied adequately, will be brought to the public's attention. Safety evaluations made from partial or narrow segments of information should be avoided when a large amount of toxicity data are available. Instead, conclusions should be drawn from all available data. Readers should understand strengths and weaknesses of the procedures for producing information used in safety assessment. Consistent with these views, this report will discuss and integrate a variety of toxicologic information. It addresses the usefulness and conduct of epidemiologic studies in humans and discusses the question of whether or not 2,4-D exposure is associated with a higher risk of cancer. The report gives particular attention to the Kansas Farm Worker study. Next, it considers some important issues surrounding the extent of human exposure to 2,4-D. Finally, a discussion is presented concerning the relevance of laboratory animal studies in evaluating the safety of humans exposed to chemicals in general and to 2,4-D in particular. Throughout the report, an attempt has been made to engender an understanding of the methods by which information regarding chemical safety is generated and applied to assess human risk. This report should help readers draw conclusions about the question of 2,4-D safety. It should also provide the public a better appreciation for the difficulties involved in arriving at final conclusions regarding the safety of chemicals introduced into the environment. �Epidemiologic Studies The Nature of Epidemiology Epidemiology is the science that examines the distribution and causes of disease in populations. When exposure of humans to certain chemicals is suspected of causing disease, epidemiologists gather information on the extent of human exposure to the chemical. They use statistical methods to link exposure to an increased incidence of the disease. The goal of an epidemiologic study is to provide an accurate estimate of disease risk associated with an exposure situation. Readers should understand that no substitute exists for human epidemiologic studies. However, they are expensive to conduct, difficult to design, and the results arc rarely as clear as everyone would wish. Nevertheless, epidemiologic studies can provide information on adverse health effects caused by human exposure to physical, chemical, or infectious agents. Some epidemiologic studies of health effects provide clear and straightforward answers. One example is the association between cigarette smoking and lung cancer. Another is the clear-cut association between alcohol drinking and automobile-related fatalities. A third example is the harmful effects of radiation such as those produced by the atomic bombs on the exposed human populations of Nagasaki and Hiroshima. Little doubt exists about the cause of disease or death in these studies because of the severe impact on health caused by smoking, by alcoholrelated impaired driving performance and by high radiation levels. On the other hand, when we consider whether or not exposure to a particular pesticide such as 2,4-D causes adverse health effects, the reader will notice that a clearcut answer is difficult to obtain. Several factors may contribute to this difficulty. First, the chemical in question may not provide severe enough biological damage to be easily detected as a causative agent by epidemiologic methods. In addition, the disease under scrutiny may have multiple causes that confound the identification of the pesticide as a contributing factor. Whether or not low intermittent exposure to a particular pesticide or chemical over a period of 20 to 30 years, for example, can contribute to the cause of cancer docs not represent a simple scientific query. Note that cancer has an incubation period of 10 to 20 years in humans. Any other event or exposure, in addition to the pesticide, occurring during the preceding years must also be considered as a possible cause of the cancer. Exposure to radiation for treatment of a tumor, occupational exposure to asbestos, tobacco smoking, and heavy alcohol use, or any combination of such factors, would make it difficult to assign the cause of cancer to pesticide exposure alone. Studying the causes of major long-term illnesses, scientists in this field usually use two primary methods. The first is the cohort study in which the emphasis is on locating and studying an indisputably exposed group of individuals. The term "cohort" indicates a group of individuals who share a similar degree of exposure to a chemical. Factory workers exposed repeatedly to a suspected cancer-causing agent would represent a typical cohort. A "control cohort" means a group of relatively nonexposed persons. Researchers compare the incidence of disease (e.g., cancer) in the exposed cohort to the incidence of disease in a nonexposed control cohort. Individuals in the control group are often matched as closely as possible in age, sex, and lifestyle to the persons in the exposed group. Time between initiation of exposure and the measurement of the disease's appearance must be considered. Cancer, as noted above, may not appear for 10 to 20 years after sufficient exposure has occurred. Cohort studies tend to be small in terms of total number of persons involved. Large numbers of exposed persons often are not available, and the number of exposed persons having a particular disease (e.g., cancer) may be small indeed. Another type of study is the case-control study. It is superior to the cohort study in its ability to detect differences among groups in the total population, in part because the case-control study can use all cases of a disease from a large population. The larger the number of cases, the more accurately scientists can detect causes of disease. Disease-free persons selected for a control group are matched by age, sex, race, or other relevant variables with persons in case groups. Researchers interview individuals in case (disease) groups and control groups to learn of possible exposures to the suspected agent (e.g., 2,4-D) in the preceding 10 to 20 (or more) years. Difficulties do exist in asking questions about exposures which may have occurred repeatedly over the preceding 20 or more years. Unless exposures were dramatic, persons in case groups and control groups may lack accurate recall of events surrounding possible exposure. Accuracy of recall represents an inherent problem in most case-control cpidemioiogic studies. Some persons may forget exposure (under-reporting), while others may think they were exposed when they were not (over-reporting). A link between exposure and the disease is detected when there is a higher than normal incidence of the disease in groups of individuals exposed to the chemical. Finally, the epidemiologist must �INCREASES IN CANCER INCIDENCE determine that no significant difference other than that of chemical exposure exists between cases and controls to explain the increased occurrence of the disease. WHITE FEMALES, 1975-84 Studies of2,4-D As A Possible Cause of Human Cancer Swedish epidemiologists reported results from a casecontrol study in the late 1970's indicating that Hodgkin's disease, non-Hodgkin's lymphoma, and soft tissue sarcoma occurred more frequently in forestry workers and farmers who were regularly exposed to phenoxy herbicides, including 2,4-D (Hardell and Sandstrom, 1979; Eriksson et al., 1981). It must be said that these three forms of cancer are not as easy for pathologists to identify and classify as are some other forms of cancer. Of the three, Hodgkin's disease (HD) is the most concisely described and defined. Pathologists have more often disagreed over the identification and classification of soft tissue sarcoma (STS) and non-Hodgkin's lymphoma (NHL). Disease classification difficulties can lead to problems with interpretation of the results obtained in epidemiologic studies. The results from Sweden associating phenoxy herbicide exposure in forestry and agricultural workers to an increased risk for HD, STS, and NHL were severely criticized in scientific debate. In addition to possible disease classification problems, criticism focused on a lack of scientific rigor in the design of the studies. Forestry workers were exposed at that time to multiple pesticides, including 2,4,5-T, which is known to contain a dioxin contaminant that causes cancer in animals. Other criticisms included lack of adequate exposure information, bias in the recall of exposure, and lack of a clear dose response relationship. Despite their deficiencies, however, the Swedish studies pointed out the need for further investigations. After the Swedish reports, case-control studies were made of New Zealand agricultural workers exposed to phenoxy herbicides (Smith et al., 1984; Pierce et al., 1986) and Vietnam veterans possibly exposed to Agent Orange, a 1:1 mixture of 2,4-D and 2,4,5-T (Greenwald et al., 1984). The results showed no increased risk of cancer due to exposure. These studies also have been criticized for some of the same reasons as were the Swedish studies. A more recent report presents results of a case-control study in Washington state (Woods et al., 1987). It shows a small increased risk of NHL in forestry workers and farmers who may have had prolonged exposure to herbicides and other types of occupational chemicals, but the results also show that increased risk could not be associated with any specific phenoxy herbicide product, including 2,4-D. A number of cohort studies have been conducted using individuals known to have experienced exposure to 60 WHITE MALES, 1975-84 40 t; 30 10 Hlii...... :->„ Figure 1. Increases in cancer incidence over a ten-year period in the United States. (From: 1986 Annual Cancer Statistics Review, December 1986, National Cancer Institute). The large increase in lung cancer in females is believed to result from a change in smoking habits many years ago. The cause is unknown for the increase in Non-Hodgkin's Lymphoma (NHL) in both sexes. Decreases in some forms of cancer have occurred over this period and are not shown here. 2,4-D. The Ranch Hand report on Air Force Personnel (Wolfe ct al., 1985), the Ontario Hydro Study on Forestry Workers (Green, 1986) and a report on manufacturing personnel (Bond et al., in press) all indicate no link between 2,4-D exposure and cancer of any type. Although each of these studies contains relatively few exposed individuals, thus limiting their ability to detect an association between 2,4-D and the disease, it is persuasive that all three have obtained the same result. The Kansas Study For unknown reasons, deaths from NHL have increased 20 to 30% since 1975 across the United States (Figure 1; National Cancer Institute, 1986). Investigators assume causes for such an increase may have occurred 10 to 20 years ago. What factors could have contributed to this steady, gradual rise? National Cancer Institute �(NCI) epidemiologists questioned whether the introduction of herbicides into general agricultural use after 1946 could be a contributing factor. Geographic frequency maps of these lymphomas suggested possible higher incidence in agricultural areas in Iowa, Nebraska, Minnesota, and Kansas (Pickle et al., 1987; Cantor, 1982). These are areas where herbicide use has been quite intensive. Realizing that multiple causes of cancers such as HD, STS, and NHL may exist, NCI investigators launched a well-designed case-control study in Kansas attempting to find an association between these cancers and exposure of farmers to herbicides, including 2,4-D. Scientists used a statewide cancer registry in which all cases of the three cancers detected within six years had been recorded. There were about 200 cases of each of the three types of cancer. People having these tumors were matched with control persons who did not have cancer. Researchers matched control (noncancer) persons using age, sex, race, and vital status (living or dead), since the study included both living and deceased cases. Results of the Kansas study were widely publicized in the mass media, with news reports leaving the impression that exposure to 2,4-D produced an increased risk of cancer. The study did conclude that herbicide exposure to farmers under certain circumstances produced a higher incidence of NHL, but unlike the earlier Swedish studies, researchers found no association between herbicide exposure and STS and HD. Thus, the Kansas study only partially supported the Swedish results. This lack of complete agreement between different epidemiologic studies is not unexpected. A general lack of agreement among epidemiologic studies attempting to link 2,4-D and cancer has existed. The Kansas study results indicate that farmers exposed to herbicides more than 20 days per year show a six-fold increased risk of NHL relative to nonfarmers. Farmers who didn't take protective measures when using herbicides showed the highest risk. Farmers who used protective measures or who did not directly apply the herbicide themselves experienced no increased risk of NHL. Should other studies confirm these results, it would indicate that if a true risk of cancer from phenoxy herbicide exposure exists, users can reduce it to very low or undetectable levels when they take appropriate care applying the chemicals. The Kansas and Swedish studies do agree that there is a link between herbicide exposure and NHL. Scientists have argued, however, that the Kansas study contains several weaknesses which would tend to invalidate its conclusion that 2,4-D exposure results in an increased risk of developing NHL. (MacMahon, 1986; Morgan, 1986). A fundamental problem with a case-control study is lack of accurate recall in an interview (Bradburn et al., Non-Hodgkins Lymphoma Colon/Rectum 14.3% 3.4% Oral 3.2% Lung 15.7% Fifteen Other Sites 31.3% Figure 2. Incidence in 1984 (age-adjusted) of various sites of cancer in men and women of all races. (Data taken from 1986 Annual Cancer Statistics Review, National Cancer Institute, U.S. Public Health Service, page HI-B-19) 1987). Farmers in the Kansas study were asked to remember details of herbicide application that occurred over 20 years ago. If a farmer had died of cancer, his widow or children were asked to recall details such as the type of herbicide, the number of years of use and the days used each year. It is unlikely that an accurate picture of exposure can be gained this way. Certain results of the Kansas study show these inaccuracies. For example, 75% of farmers or their relatives said they used no herbicides on their farms. This result cannot be correct given Kansas agricultural practices. This then is an example of large scale under-reporting of herbicide use. A consistent dose-response relationship docs not exist in the data obtained from Kansas farmers. Comparing cancer patients who had used herbicides for more than 26 years with those using them for six years did not show that longer use caused a higher risk of NHL. Another criticism is that the number of cancer cases in each exposure group was small. Often researchers calculated an increased risk based on the assignment of two to five cancer cases to a particular exposure group. Because the degree of exposure was based on memory or recall during an interview, which is recognized to be a relatively inaccurate process, errors in the assignment of cancer cases to a particular exposure group are expected. With so few cases in each exposure group, a small number of inaccurate exposure assignments can invalidate the conclusion that a particular exposure group exhibits a higher cancer risk. NHL is a relatively rare form of cancer, representing 3.4% of all cancer cases nationally (Figure 2; National �Cancer Institute, 1986). The small number of cases in a farming state such as Kansas makes detection of a cancer-causing effect of herbicides extremely difficult. If herbicide exposure in connection with farming causes a slight increase in NHL, relatively few cases can be expected to occur from this type of exposure. If a cancer with a higher incidence in the population (e.g., lung or colon/rectum) were being studied in connection with 2,4-D use, a larger number of cases would be involved and the likelihood of obtaining a statistically valid conclusion would be increased. In spite of criticisms, the Kansas study is believed to represent a useful epidemiologic study. Such studies are recognized to have inherent problems and limitations (Colton, 1986), but most experts reviewing the Kansas study acknowledge the skill, size, scope, and quality of the investigation. They do not agree with the authors, however, that it is a strong or specific finding. Where does this leave the reader and the public? In general, knowledgeable scientists do not feel confident in connecting NHL and unprotected, prolonged use of 2,4-D. Nonetheless, it can be acknowledged that a statistical association has been revealed among a very small subgroup of Kansas farmers who applied herbicides without protection for an extended period of time. Researchers did not investigate whether viral infection, family history of cancer and radiation exposure—all suspected causes of NHL—could have occurred more frequently in the herbicide-exposed farmers. Nevertheless, readers must accept results from the Kansas study as a single piece of evidence in the solution of a puzzle demanding many pieces of evidence. It does not represent sufficient proof that exposure of the public to 2,4-D under its normal use constitutes a cancer risk. Other evidence is necessary, and this should become apparent upon reading subsequent sections of this report. Ongoing Studies At the present time, two other large case-control studies are in progress that will yield additional information on phenoxy herbicide exposure as a possible cause of cancer in humans. These studies are similar to the Kansas study and are being conducted in Iowa, Minnesota, and Nebraska by investigators from the National Cancer Institute. Those studies may or may not eventually confirm results found in Kansas. A preliminary report of results obtained in Iowa and Minnesota presented at a Soil Science Society of America meeting, indicates that no increased risk of NHL in farmers exposed to 2,4-D occurred (Cantor and Blair, 1986). Regardless of the final outcome of these studies, more definitive information will be available after their completion in 1988. �Human Exposure to 2,4-D Consideration of possible adverse human health effects caused by 2,4-D requires knowledge of the extent of human exposure to the chemical. Assessing human exposure is one of the most difficult steps in calculating human health risks ascribed to chemicals. This section of the report will consider human exposure to the herbicide 2,4-D as it may occur in factory workers, chemical applicators, and in the general public. Manufacturing Personnel Epidemiologists have conducted studies on the health of factory workers manufacturing 2,4-D. Most published cohort epidemiological studies on the health of workers engaged producing 2,4-D do not include information on the amounts of 2,4-D to which they were exposed. One noteworthy exception is the mortality study by Bond et al. (1987). That report gives results of industrial hygiene measurements in 2,4-D-exposed workers performing different types of manufacturing operations from 1949 to 1983. Researchers measured concentrations of 2,4-D in the air surrounding workers. The highest amount of the herbicide found in the air was 4 milligrams per cubic meter (mg/m3). This occurred in 1949 and involved operation of a drier. The next highest level recorded that year was 0.4 mg/m3. These amounts were reduced over the years in that operation. By 1983 values ranged from none detected to 0.01 mg/m3. In these workers, no excessive deaths occurred from cancer or any other disease that scientists could attribute to 2,4-D exposure. Particular attention was given to studying the possibility of increased brain tumors, soft tissue sarcomas and lymphatic cancers in the workers. Like many cohort epidemiological studies, this one had relatively small numbers of subjects available for study. However, the results showing a lack of association between 2,4-D exposure and cancer conform to those from other studies of workers engaged in manufacturing 2,4-D (Axelson et al., 1980; Riihimaki et al., 1982; Wiklund and Halm, 1986). These studies, each containing small numbers of exposed individuals, combine to give substantial evidence that a cause and effect relationship between 2,4-D exposure and mortality from any cause docs not exist. 2,4-D or other herbicides that enter the bodies of applicators. Much of this variation is due to decided differences in applicators' work habits and hygienic practices. Some did not wash their hands, wore the same clothes all week long, and cleaned out plugged sprayer nozzles by blowing through them with their mouths. Others wore rubber gloves and supervisors made sure they avoided excessive contact with the herbicide. These workers washed their hands after contact with herbicides and changed clothes and showered daily. However, these reports all agree on the following: (1) inhalation of 2,4-D from the atmosphere due to spraying operations is minimal and need not be considered when determining worker exposure; (2) the major route of exposure is dermal, especially from hand contamination; (3) only about 6% of 2,4-D deposited on the skin is absorbed and the absorption rate is slow; (4) absorbed 2,4-D is excreted rapidly in the urine; and (5) the total amount of 2,4-D excreted in urine is approximately the same as that absorbed into the body after herbicide exposure. Forestry Applicators An excellent study by Frank et al. (1985) concerned the exposure of forestry workers engaged in applying 2,4-D from helicopters at the rate of 1.4 pounds per acre. This study is of particular interest because herbicide application in forests has been a major concern to some people, and has generated great attention from the media. The report includes two noteworthy points. First, from estimates of 2,4-D in urine, the highest dose to any worker was 0.022 milligrams per kilogram (mg/kg) of body weight per day. One method of judging the risk of 2,4-D exposure to humans is to compare this dosage with an acceptable daily intake (ADI)a of the herbicide in our diet. In 1971 the United Nations World Health Organization (WHO) and the Food and Agricultural Organization (FAO) appointed scientific panels which established an acceptable daily dietary intake of 2,4-D of 0.3 mg/kg of body weight per day. Comparing a 0.022 mgAg/day dose in the highest exposed forestry worker to the ADI value of 0.3 mg/kg/day, workers could absorb approximately 15 times more 2,4-D before reaching the level scientists have deemed an unacceptable daily intake. The second major point of Frank et al. (1985) arose Applicator Exposure Applicator exposure to phenoxy herbicides, especially 2,4-D, has been carefully studied in Canada, Europe, Turkey, Scandinavia, and the United States. Research results vary considerably as to the actual amounts of a An ADI is the estimated maximum amount of a material that people could eat every day of their lives without harmful effects and is based on knowledge gained from laboratory animal studies. An ADI value is calculated using a safety factor to account for sensitivity differences among humans and between humans and laboratory animals. �8 from results obtained from a human volunteer who stood directly under the spray swath for a single exposure. The chemical was applied at a rate of 1.4 Ib of 2,4-D per acre and from a height of 36.6 feet. This is approximately twice the rate that workers would apply to a lawn. To create a "worst case" situation, spray was allowed to dry and the volunteer did not shower or change clothing. The amount absorbed was 0.44% of the total amount of 2,4-D deposited on the skin and clothing (shorts, T-shirt and sneakers). It totaled 0.0045 mg/kg of body weight. In this exaggerated exposure case, the dose of 2,4-D was only 1.5% of the ADI value for 2,4-D. Using the latest no-observed-effect-level (NOEL)*3 of 1 mg/kg for 2,4-D in laboratory animals (Mullison et al., 1986), this exaggerated human exposure resulted in a dose more than 200 times below that dose to which rats have been exposed for a lifetime without showing any adverse health effects. Since this result was from an exaggerated exposure situation created around one person, other researchers may or may not be able to reproduce its results. Nevertheless, the result agrees with other results indicating that exposure of 2,4-D to applicators or bystanders is not likely to produce overt toxicity. Kohli et al. (1974) and Sauerhoff et al. (1976) conducted experiments to study the metabolism and excretion of 2,4-D. Human volunteers ingested single doses of 5 mg/kg of 2,4-D without observed ill effects. The rapid excretion of 2,4-D in the urine found in this study indicates that the chemical will not accumulate in the body upon repeated exposure. Nash et al. (1982) state that a 50- or 60-year-old, 80 kg (175 Ibs.) farm or forestry worker with 30 years' exposure to 2,4-D for 30 days each year, may absorb and excrete 900 mg of 2,4-D in a lifetime. A lifetime intake in applicators ranging from 36 mg to 2900 mg has been calculated from urinary excretion data as reported by the Canadian Centre for Toxicology (1987). The range of exposures is large because the extent of lifetime exposure depends upon the total number of days during which an applicator applies 2,4-D. General Public A common use for 2,4-D is to control weeds in turf, particularly home lawns. What are the health risks when home "do-it-yourself" applicators treat their lawns? The answer to this question can be formulated using two primary factors: First, an estimate of the toxicity of 2,4-D to humans and second, an estimate of the human exposure resulting from an application to a lawn. Spraying 2,4-D as a liquid or applying it in a granular b NOEL is the daily dose that causes no adverse effects when fed to laboratory animals for extended periods (up to a lifetime). fertilizer are the two usual methods by which 2,4-D is applied to lawns. The chances of human exposure are greater with spraying than with the use of the granular form because 2,4-D liquid concentrate normally is used to prepare the actual spray solution that is applied. Splashes and spills can occur when handling the concentrate, resulting in possible exposure to any part of the body that is not protected. Applicators may also have contact with the spray itself unless they wear protective clothing. By contrast, when the herbicide is applied with a granular fertilizer, the applicator does not handle a 2,4-D concentrate. Most fertilization is done using small gravity-fed mechanical devices an applicator pulls or pushes across the lawn. Since fertilizer particles are larger and more dense than spray droplets, they are less likely to be blown by the wind. Furthermore, applicators stand little chance of absorbing 2,4-D from the dry particles when they walk in shoes on treated grass. Two other aspects of exposure to 2,4-D when it is used for weed control in lawns are the length of time required to treat a lawn and the number of treatments per season. Estimates show a lawn of moderate size, perhaps 50 feet x 100 feet, would require a maximum of one hour to treat whether sprayed or fertilized. Lawns measuring !/2 to % of an acre probably would not require more than three hours. For large areas the applicator probably would use larger and more efficient equipment. Typically, 2,4-D is applied once or twice during the season, often with ten or more weeks between applications. A home owner spraying a large lawn twice a season could have skin exposure for a maximum of six hours. When compared to exposure commercial applicators and certain agricultural workers experience, this represents a much lower health risk situation. If homeowners wear protective clothing—always a prudent precaution when spraying any pesticide—they increase their margin of safety. Scientists have collected some data from experiments measuring the actual human exposure to 2,4-D from a lawn application. A commercial lawn care company studied 45 of its employees over a period of three work weeks to determine the amount of 2,4-D they absorbed when applying the herbicide (Yeary, 1986). The 45 workers were stationed at five different locations. The daily amount of 2,4-D that entered their bodies as estimated from urinary excretion measurements varied from 0.0025 mg/kg to 0.0035 mg/kg of body weight. Since the ADI value is 0.3 mg/kg, it was concluded that an adequate safety margin existed for the lawn care applicators. Approximately 100 times more 2,4-D would have to enter a worker's body each day before reaching the ADI value. A frequent question people ask concerning 2,4-D is the extent of exposure that occurs from walking or sitting on newly sprayed lawns. Data measuring this type of �exposure are not abundant, but some information is available from which estimations using an exaggerated "worst case" situation can be made. Thompson et al. (1986) provided information indicating the amount of 2,4-D that can be dislodged from a dry, newly sprayed lawn. Based on their results, a commonly used application rate of 0.75 Ib/acre would give a dislodgeable residue of 0.35 mg of 2,4-D per square foot of lawn on the day of application. The imagined situation is one in which a child plays on a lawn that, unknown to the parents, has been sprayed with 2,4-D. Assuming that a 22 Ib (10 kg) unclothed baby rolled on 10 square feet of this lawn, absorbing 6% of the dislodged 2,4-D through the skin, that child would receive a dose of 0.02 mg/kg of 2,4-D. How does this dose compare to a dose that has produced no harmful effects (including cancer) in laboratory animals given 2,4-D in the diet for a lifetime? Rats and mice have received 1 mg/kg per day in the diet for a lifetime without measurable changes occurring in any organs or tissues (Mullison, 1986). Assuming a similar sensitivity to that of test animals, the baby could receive a 50-fold higher dose and still not be above a dose that can be given to animals for a lifetime without causing adverse effects. For another comparison, the baby would receive a dose totaling 7% of the ADI, taking that value as a safe standard. These types of calculations provide some assurance that exposures during or after lawn treatment with 2,4-D are low. Comparison with results from animal studies show they represent no real health concern. However, it would be reassuring to have substantiating information on exposure derived from actual measurements of 2,4-D excretion in the urine of persons who had been in contact with sprayed lawns. Researchers could construct more accurate estimates if they possessed better information on exposure resulting from 2,4-D treated lawns. Environmental Sources of Exposure It is worthwhile to briefly consider the general public's exposure to 2,4-D in air, soil, food, and water (Mullison, 1987). The concentration of 2,4-D in the air during spray application was 2.1 micrograms per cubic meter (ug/m3). Subsequent dilution in the general air mass reduces the general public's exposure away from the spraying area to extremely low amounts. For many years Food and Drug Administration officials have conducted market basket surveys to determine pesticide levels in food. From 1965 to 1970, they found negligible traces of 2,4-D (15,000 times less than the ADI ofO.3 mg/kg)in the food (Mullison, 1981). From 1971 to 1973, they found an even smaller amount. From 1974 to 1985 they found no trace of 2,4-D. Soil surveys in agricultural use areas have shown little or no 2,4-D, which is not surprising since 2,4-D undergoes rapid degradation in soil under good plant growth conditions. Broadleaf plants are very sensitive to 2,4-D and can show the chemical's presence in soil. Over the 40 years that 2,4-D has been applied, under normal use conditions, no reports of its accumulation or persistence in soil at concentrations harmful to plant life have been reported in the scientific literature. Water is a natural resource that is receiving a great deal of research attention. Several general surveys have shown 2,4-D does not accumulate in rivers, lakes, or groundwater. Traces occasionally have been found (usually less than 1 part per billion parts of water (ppb) or 0.001 mg/liter). In light of the large amount of laboratory data on levels of 2,4-D harmful to animals, this low amount cannot be considered a problem. Federal regulations published in 1975 allow 100 ppb of 2,4-D in drinking water and a March 31, 1987 EPA health advisory indicates that lifetime exposure should not involve drinking water containing more than 70 ppb. Conclusions Regarding Exposure Information is available on the exposure of farmers, foresters, pesticide applicators, and the general public to 2,4-D. It shows that persons are not exposed to hazardous amounts of 2,4-D when label recommendations and prescribed methods of application are used. This statement can be made in view of the short life of 2,4-D in the environment; its rapid excretion in mammals, including humans; its moderate acute toxicity; and except for occasional traces, its virtual absence from the food we eat, the water we drink, and the air we breathe. �10 Toxicity Studies in Laboratory Animals The potential for 2,4-D to produce harmful effects in man can be estimated using knowledge gained from studies of its toxic effects in laboratory animals. Researchers have conducted and reported on animal toxicity tests throughout the more than 40 years that 2,4-D has been used as a herbicide. Hundreds of relevant scientific reports have been published. This report makes no attempt to review them. Rather, we will provide a discussion of the importance and limitation of animal studies and summarize the conclusions that can be drawn regarding the potential toxicity of 2,4-D in humans. Advantages and Limitations of Animal Studies Animal toxicity studies continue to be an integral and essential part of evaluating human risks. While a variety of microbial, cellular and tissue systems are available for screening selected potential effects, a thorough evaluation of the response of a complex mammalian animal system remains the most comprehensive way to test the toxicity of a chemical. Part of the science of toxicology is extrapolating from experimental effects in animals to human risk. Animal testing presents sonic unique advantages and some distinct limitations in the risk evaluation process. An advantage of animal testing is that researchers can deliver measured dosages of chemicals in a controlled manner by several exposure routes. They can use appropriate controls at each important phase of research. Because certain laboratory animals can ingest, absorb, metabolize, and excrete chemicals similarly to man, attempts are made to select test animals that handle each specific tested chemical in a manner most similar to humans. Thus, the species of test animal is important. For one chemical mice may make better predictors for humans, while for a different chemical, rats may be more predictive. Increasing response to increasing dosage is another basic principle of toxicology. Animal dosing studies are valuable, because controlled chemical administration can be used to elicit the dose-response relationship in a predictable manner. The more predictable and controlled a test animal's response, the more reliably researchers can make comparisons to human beings. Another advantage in using test animals is that researchers can select age, sex, state of health, nutritional factors and reproductive status, which may facilitate prediction for specific human populations such as the developing fetus or a malnourished individual. Thus, prediction is enhanced by being able to target specific risk factors. In addition, chemical administration can be selected for short- or long-term evaluation. This can be done over an animal's entire life, as in cancer studies. Animals may be given dosages of chemicals substantially beyond the expected human exposure. This fact allows the fullest expression of adverse response and increases assurance that the possibility of a toxic response in humans will not be missed. Commonly, the lowest dosage in animals causing no observed effect, NOEL, is used to calculate an ADI for man. Usually, the NOEL determined in animals is divided by a factor of 100 to 2,000 to calculate an ADI for humans. In this way a safety factor is introduced to insure that humans are protected should they be more sensitive to a particular chemical than arc laboratory animals. Some inherent limitations of animal studies must be considered: (1) The genetic makeup of all animals is unique, and one can never find an animal model that is exactly the same as the human. (2) Spontaneous disease in animals may alter the response to chemicals in a way not duplicated by human disease. (3) Animals usually do not live as long as humans. (4) Animals possess different metabolic rates than humans. (5) Anatomical differences from humans such as placental type may not allow precise prediction of placental response or fetal susceptibility to chemicals. (6) For cancer studies, spontaneous tumors in an animal population may be quite different than in humans. (7) Homogeneity of responses in animals may not adequately reflect heterogeneity in the human population. (8) Seasonal and diurnal variables maybe important in animal studies but not applicable to a human population. (9) Finally, it should be noted that animal studies use relatively small numbers of subjects due to logistical and cost factors. Such studies must depend on tightly controlled experimental conditions and statistical evaluation of the results. Toxicity of 2,4-D from Single and Repeated Doses Laboratory animal studies evaluating the ability of 2,4-D to cause death after a single high dose have indicated that the chemical shows moderate acute toxicity (World Health Organization, 1984). The LDfo (lethal dose in 50% of the animals tested) ranges between 300 mg/kg and 1000 mg/kg, depending on the animal species and the type of 2,4-D formulation tested (World Health Organization, 1984). Dogs are slightly more sensitive than most species to 2,4-D's lethal effect. In that species the LDso is approximately 100 mg/kg. Humans have ingested large amounts of 2,4-D in suicide attempts and have survived single doses on the order of 100 mg/kg (Berwick, 1970). It is not unreasonable to �11 speculate that the LD$Q in humans is in the same range as that for the majority of animal species tested. Lethality studies also have been conducted by administering smaller doses of 2,4-D each day over a 3to 16- week period. Researchers have tested many species and compiled the results for review (World Health Organization, 1984). These studies indicate that scientists have observed no adverse effects at doses of 30 mg/kg/day in rats or 10 mg/kg/day in dogs. Other toxicity studies indicate that 2,4-D is not extremely more toxic when given over a long period of time because the chemical does not accumulate in the body after prolonged exposure. Researchers do not know the precise cause of death after ingestion of large doses of 2,4-D. Damage to muscles and nerves controlling muscular movement has been suggested in the acute (single, high dose) toxicity of the chemical (Singer et al., 1982; World Health Organization, 1984; Wagner, 1983). Recent neurological studies in laboratory animals, however, do not indicate an effect of 2,4-D on the nervous system (Toyoshima et al., 1985; Mattsson, Albee et al., 1986, Mattsson, Johnson et al., 1986). The occurrence of 2,4-D toxicity after a massive dose in humans represents a rare situation and detailed information from this type of medical emergency is not readily available. Studies of the toxicity of 2,4-D given in single, high doses may not help to predict human effects from 2,4-D that might occur when applicators use the chemical as a herbicide. More relevant are studies in which animals are exposed to much lower doses of 2,4-D for nearly a lifetime. Recent results from lifetime feeding tests show no adverse effects in rats and mice fed 1 mg/kg/day (Mullison, 1986). Somewhat higher daily doses than these (e.g., 45 mg/kg) produce a loss of body weight and slight changes in the kidneys of the animals, while still higher doses will shorten their lifespan. Researchers have tested whether or not 2,4-D causes birth defects and altered reproduction in laboratory animals. Results from studies in several different species have been compiled (Wagner, 1983). Doses greater than 80 mg/kg to pregnant animals will cause some fetal death. Lower doses show lesser effects in offspring (e.g., lower birth weight). Doses below 10 mg/kg to pregnant rats produce no adverse effects on offspring. Harmful effects of 2,4-D observed in testing laboratory animals occur at doses that are very high compared to those occurring in humans using 2,4-D. Human exposure to single or multiple life threatening doses of 2,4-D only occurs in an accidental or catastrophic situation, or due to intentional ingestion. On the other hand, we know that low doses of some chemicals can produce cancer. Safety testing of most chemicals includes animal tests to evaluate their potential for causing cancer. Cancer Testing Using Laboratory Animals Cancer represents a change in normal cells resulting in their uncontrolled growth and loss of normal function. Cells in the body that are transformed by cancer can exist in a particular organ, such as the lung. They may multiply to produce a tumor which eventually damages the organ. Cancer cells may spread to other organs, causing multiple sites of damage. This uncontrolled growth and spread may continue until death ensues. The process by which normal cells change into cancer cells is called carcinogenesis. Both chemicals occurring in nature and synthetic chemicals may cause cancer. Viruses, bacteria, other life forms, and radiation may also contribute to the carcinogenic process. Normal cells may transform into cancer cells, involving at least two distinct stages termed initiation and promotion. Initiation, the first and primary event, involves a change in DNA, the genetic material carried in all cells of the body. A chemical could cause change by attaching itself to DNA or by participating in biochemical processes ultimately resulting in abnormal DNA. Creation of abnormal DNA in a cell also can occur spontaneously, unrelated to the presence of a foreign chemical. Cells can repair DNA damage, whether it is caused normally or due to attack from foreign chemicals. However, sometimes the repair system is overwhelmed by an excess of a DNA-damaging chemical. If a cell does not repair damaged DNA, it is initiated or primed to change into a cancer cell. Then the initiated cell undergoes a chemically-induced change called promotion. A chemical acting as a promoter changes an initiated cell into a cancer cell. Scientists do not understand the processes connected with promotion as well as those connected with initiation. A single chemical can act both as an initiator and a promoter, producing cancer by itself. In other cases, two chemicals are involved, one causing initiation and another causing promotion. Chemicals that act only as promoters will not damage DNA. They can only cause cancer if critical DNA damage already has occurred as the result of naturally-occurring events or due to the presence of a DNA-damaging foreign chemical. Laboratory tests are available to determine whether chemicals can act as initiators or promoters. Several procedures are available to examine whether a particular chemical can damage DNA. These tests often use animal cells or bacteria and are usually carried out in a test tube. They require only 1 to 2 days and can detect initiators (also called genotoxic or mutagenic chemicals). A chemical causing unrepaired DNA damage will produce detectable mutations in cells growing in a test tube. This provides a signal that the chemical may cause cancer. Short-term tests for chemicals that act as pro- �12 moters are not yet available. Current methods to detect a promoter require its repeated administration to animals that have previously received a single dose of a DNAdamaging chemical. Detection of promoters requires waiting months for animals to develop tumors or lesions that will become tumors. Tests for initiators (mutagenic chemicals) are performed regularly, but tests for chemical promoters are carried out less frequently. The ability of a chemical to produce cancer (i.e. tumors) in laboratory animals is usually assessed before the government approves that chemical for a use that may involve human exposure. Cancer tests are conducted by exposing rats and mice to the chemical for nearly a lifetime period (approximately two years). The chemical is usually placed in the animals' feed, but can be given by other means. Individual groups of animals are given different amounts of chemical in their feed. A control group receives no chemical treatment. Typically, three different amounts of chemical are given to three groups of animals for low-, medium-, and high-dose treated groups. Researchers choose a maximum tolerated dose (MTD) for the highest dose. This MTD produces some measurable effect on the animal, such as a small loss of body weight besides possibly causing cancer. Lower-dose animal groups may exhibit no obvious effects from the chemical and may or may not produce cancer as determined by microscopic analysis. Even the lowest dose administered usually will be much higher than that to which humans may be exposed each day. Scientists must use high doses in these animal tests because their goal is to detect a chemical's cancer-causing potential. It would be useless in animal cancer tests to attempt to mimic expected human exposure. Relative sensitivities of animals and humans to cancer induction are never known at the time researchers conduct the test. After approximately two years of chemical exposure (about the lifetime of the test animal), the animals are sacrificed. Using microscopic techniques to visualize structural details of the tissue, pathologists examine all major organs for evidence of cancer. The number of cancer sites (tumors) in each animal is recorded. A certain number of animals in each study group may be sacrificed after one year of exposure to examine whether tumors are present at a younger age. Tumors may be present in some control animals, i.e., animals that receive no chemical treatment. These animals exhibit the normal rate of cancer due to causes not related to chemical exposure. If significantly more animals in the treated groups exhibit tumors than in the control group, the inference is made that the chemical caused an increased incidence of cancer. More animals should exhibit cancer as test chemical doses increase. This dose-related increase in cancer incidence strengthens the conclusion that the chemical causes cancer. A small increase in cancer incidence observed only in the animals receiving the highest dose is somewhat less conclusive. Cancer testing also must determine a dose that docs not produce an increase in tumor incidence. No increase in tumors related to chemical exposure should appear in animals receiving the lowest test dose of the chemical. Attempts to detect cancer-causing properties of chemicals using relatively high doses in laboratory animals represent well-accepted procedures in toxicology. Researchers have found many cancer-causing chemicals this way. They have associated only a small fraction of these chemicals with cancer occurrence in humans. Two reasons suggest themselves for why humans exposed to chemicals that produce cancer in laboratory animals do not show increased cancer rates. First, epidemiologic methods used to detect causes of cancer in humans are less sensitive than the animal testing procedures described above. Next, laboratory animals are not always identical to humans in their responses to chemicals. Nevertheless, scientists rarely find a human carcinogen that does not cause cancer in animals. This degree of predictability provides a basis for continued use of animal testing procedures to detect cancer-causing chemicals and to estimate the risk of chemical-induced cancer in humans. Carcinogenicity of2,4-D in Animal Studies Early attempts to determine if certain phenoxy herbicides cause cancer may have been confounded by traces of dioxin impurities resulting from the chemical manufacturing process. The most notable example was the presence of a potent, cancer-causing dioxin (2,3,7,8TCDD) in the herbicide 2,4,5-T. Dioxins occasionally found in 2,4-D are not among the most toxic types of these persistent chemicals (Environmental Protection Agency, 1980). This explains why toxic changes observed in laboratory animals treated with high doses of 2,4-D over an extended period of time are not the same as toxicity occurring from administering potent or nonpotent dioxins (EPA, 1980). Toxicity resulting from large amounts of 2,4-D exposure in animals can be attributed to the herbicide and not to dioxin contaminants. It follows that //2,4-D exposure were to cause cancer in laboratory animals, this could be attributed to the herbicide and not to traces of nonpotent dioxins. Whether or not 2,4-D itself may cause cancer in laboratory animals is not a new question. Oncogenicity studies in both mice and rats were included in the initial data for 2,4-D that were required by EPA. While no carcinogenic effects were evident in rats, mice, or dogs, the studies were considered insufficient under newer Federal Insecticide, Fungicide, Rodenticide Act (FIFRA) �13 Pesticide Assessment Guidelines. In 1980 the Environmental Protection Agency (EPA) required that these studies, in addition to many routine acute and chronic toxicological studies be repeated for product registration (Office of Pesticide Programs, EPA, 1980). One of the leading scientific groups charged with the safety evaluation of chemical substances, including food additives, pesticides, dyes, and others, is IARC, the International Agency for Research on Cancer. In both 1977 and 1982 IARC reviewed all available data on 2,4-D. It reported them inadequate for a definitive judgment on whether or not 2,4-D caused cancer in laboratory animals (IARC, 1977 and 1982). This was consistent with the EPA's decision to require additional data. Following the EPA call for more data, major manufacturers of 2,4-D formed an industry task force to sponsor the very expensive studies required to re-register their products. Two chronic feeding studies were commissioned by that task force. They have recently been completed and submitted to the EPA. While their results are subject to differences in interpretation, as lifetime feeding studies often are, readers should consider results from these two most recent studies along with previous data to address the question of whether or not 2,4-D is carcinogenic in laboratory animals. One of the recent lifetime feeding studies was conducted in Fischer 344 rats at dose levels that were clearly in compliance with the requirement for an MTD (Hazelton Laboratories, 1986). Changes were seen in the kidneys of rats given highest doses. This satisfied the MTD requirement. No abnormal changes were observed at the lowest dose of 1 mg/kg/day. This result provides a NOEL. Male rats, but not females, fed the highest dose (45 mg/kg/day) exhibited a statistically higher frequency than did concurrent study controls of a brain cell tumor known as an astrocytoma. No increased incidence of tumors occurred in rats given 1, 5, or 15 mg/kg of 2,4-D each day. Researchers have argued that the higher incidence of tumors in rats receiving the highest dose of 2,4-D is due to chance. Fischer 344 rats usually exhibit tumor development at highly variable rates. Also, an increased tumor incidence in only the highest dose group docs not represent a clear dose-response phenomenon and is not strongly supportive of the hypothesis that 2,4-D causes cancers. A report from the laboratory conducting this study stated, "This finding is, nevertheless, suggestive of a possible carcinogenic effect at a dose of 45 mg/kg/day." Indeed, 2,4-D may be a weak neurocarcinogen in rats, but this effect has been questioned because it has not obeen observed previously in laboratory animals given 2,4-D. It also appears that animal response characteristics in this study are not the same as those previously observed in tests with other neurocarcinogens (Koestner, 1986). The second recently completed chronic feeding study was conducted using mice from the cancer-sensitive B6C3F1 strain (Hazleton Laboratories, 1986). Test results exhibited no evidence of 2,4-D-related carcinogenicity in any tissue or organ system. Under current policy for chronic studies submitted to the EPA, this study did not achieve an MTD. That is, the highest dose did not produce a loss of body weight or cause other signs that the animals were not in good health. However, the highest dose used in this study (45 mg/kg/day) was 600 times the maximum reported human exposure. Even at this high dose no evidence appeared of increased incidence of cancers, including brain tumors. Known neurocarcinogens in animals are generally found to be mutagens. Scientists have conducted numerous mutagenicity studies on 2,4-D, both in vitro and in vivo. They do not support the generalization that 2,4-D is genotoxic (mutagenic). Recently, the Canadian Centre for Toxicology (1987) assembled researchers to review in great detail all available data from studies on 2,4-D that pertain to its possible mutagenicity. This expert panel examined 29 in vitro mutagenicity studies. Nineteen were negative; of the remaining 10, nearly all resulted in equivocal data (e.g., effects that were not dose-related or from test material that was not adequately identified or defined). Negative results were reported in tests using both bacterial and mammalian cell lines. Some tests on both cell lines showed positive results, but in all cases the studies can be criticized because of the use of cytotoxic doses, or conditions that in some way compromised their validity. In vivo studies on the genetic toxicity of 2,4-D also did not confirm any suggestion of mutagenicity. Canadian Expert Panel members reviewed twelve studies. Eight were negative, one yielded equivocal data and three were positive only at doses that otherwise are toxic to the organism. Research has established that 2,4-D is cytotoxic at very high doses. Mutagenicity studies are readily confounded by cytotoxicity or nonspecific cell damage. This rather large battery of studies does not provide convincing evidence that 2,4-D is mutagenic. As mentioned above, neuropathologists agree that neurocarcinogens generally are mutagens. All data showing a lack of mutagenicity for 2,4-D add further doubt to an interpretation that it produces an increased incidence of astrocytomas in Fischer 344 rats. Results from the most recent cancer studies in rats and mice do not present a clear answer regarding whether or not high doses of 2,4-D can cause an increase in tumors in laboratory animals. These results arc not unexpected because if a chemical is not carcinogenic, or is an �14 extremely weak carcinogen in animals, tests often will show mixed results. Tumors in rats and mice do normally occur. A positive test requires a slight but statistically significant increase in the normal tumor rate as a result of 2,4-D administration. Repeated attempts to show a slight increase in tumor rates with a noncarcinogen may produce a small percentage of incorrect results, but the majority of such tests should yield correct results. In the case of 2,4-D, a number of cancer studies have been conducted in rats and mice, nearly all of which have yielded results indicating that the chemical does not cause an increase in the normal incidence of tumors. In summary, evidence that feeding 2,4-D to laboratory animals causes cancer remains very weak. When assessed together with earlier animal studies, recent data do not provide sufficient evidence to warrant a serious concern that 2,4-D is an animal carcinogen. The results are consistent with those from epidemiologic studies which to date have not shown 2,4-D to increase the risk of human cancer. Other scientists who have recently reviewed available data from animal tests and epidemiologic studies in humans reached the same conclusion. In March 1987 the Expert Panel on Carcinogcnicity of 2,4-D reported to the Ontario Ministry of the Environment that "the existing animal and human data are insufficient to support the finding that 2,4-D is a carcinogen" (Canadian Centre for Toxicology, 1987). A Scientific Advisory Panel of the U.S. EPA consisting of nationally recognized scientists from the academic community has recommended to the agency that 2,4-D be reclassified from a possible human carcinogen (Group Q, to another chemical group (Group D). This reclassification recommendation shows the panel believes that inadequate human and animal evidence exists for classifying 2,4-D as a possible carcinogen for humans (Koestner, 1987; Federal Register, 1986). �15 REFERENCES Axelson, O., L. Sundcll, K. Andersson, C. Edline, C. Hogstedt, and H. Kling. 1980. Herbicide exposure and tumor mortality. Scand. J. Work Environ. Health 6:73-79. Berwick, P. 1970. 2,4-dichlorophenoxyacetic acid poisoning in man. Some interesting laboratory and clinical findings. J. Amer. Med. Assoc. 214:1114-1117. Bond, G. G., N. H. Wetterstroem, G. L. Rousch, E. A. McLaren, T. E. Lipps, and R. R. Cook. 1987. Cause-specific mortality among employees engaged in the manufacture formulation or packaging of 2,4-dichlorophenoxyacetic acid and related salts. British Journal of Ind. Med. (in press). Bradburn, N., L. J. Rips, S. K. Shevell. 1987. Answering autobiographical questions: The impact of memory and inference on surveys. Science 236:157-161. Canadian Centre for Toxicology. 1987. Expert Panel Report on carcinogenicity of2,4-D. Guelph, Ontario, Canada. Cantor, K. P. 1982. Farming and mortality from non-Hodgkin's lymphoma: A case-control study. Int. J. Cancer 29:239-247. Cantor, K. P., A. Blair. 1986. Agricultural chemicals, drinking water, and public health: An epidemiologic overview. Soil Science Society of American Workshop Paper No. 2. Madison: Soil Science Society of America. Colton, T. 1986. An editorial, herbicide exposure and cancer. J. American Med. Assoc. 256:1176-1177. EPA, Residue Chemistry Branch, Hazard Evaluation Division. 1980. Surveillance Index, Chemistry Data, 2,4-D. Washington, D.C. Eriksson,M.,L.Hardell,N.O.Berg,T.Moller,and O. Axelson. 1981. Soft tissue sarcomas and exposure to chemical substances: A case reference study. Brit. J. Ind. Med. 38:27-33. Federal Register, Vol. 51, No. 185, September 24,1986, p. 34000. Frank, R.,R. A. Campbell, and G. J. Sirons. 1985. Forestry workers involved in aerial application of 2,4-dichlorophenoxyacetic acid (2,4-D): exposure and urinary excretion. Arch. Environ. Contain. Toxicol. 14:427-435. Green, 1,. M. 1986. Mortality analysis of Ontario hydro forestry tradesmen cohort 1950-1982. Toronto, Ontario, Canada: Health and Safety Division, Ontario Hydro. Grecnwald, P., B. Kovasznay, D. N. Collins, and G. Thcrriault. 1984. Sarcomas of soft tissue after Vietnam service. J. National Cancer Inst.13: 1107-1109. Hardell, I,, and A. Sandstrom. 1979. Case-Control Study. Soft tissue sarcomas and exposure to phcnoxyacetic acids or chlorophenols. Brit. J. Of Cancer 39:711-717. Hazlcton Laboratories. 1986. Combined Toxicity and Oncogenicity Study in Rats; 2,4-dichlorophenoxyacetic Acid, final report. Vol. I. Vienna, VA: Hazelton Laboratories America, Inc., Project No. 2184-103. Hoar, S. K., A. Blair, F. A. Holmes, C. D. Boysen, R. J. Robel, R. Hoover, and, J. F. Fraumeni. 1986. Agricultural herbicide use and risk of lymphoma and soft tissue sarcoma. Journal of Amer. Med. Assoc. 256:1141-1147. IARC. 1977. 2,4-D and Esters. In: Some Fumigants, the Herbicides 2,4-D and 2,4,5-T, Chlorinated Dibenzodioxins and Miscellaneous Industrial Chemicals. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man, Vol. 15. Lyon: Int'l. Agency for Research on Cancer. IARC. 1982. IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Chemicals, Industrial Processes & Industries Assoc. with Cancer in Humans. Monographs, Supplement 4, pp. 101-103. Int'l. Agency for Research on Cancer. Kocstner,A. 1986. The brain tumor issue in long-term toxicity studies in rats. Fd. Chem. Toxicol. 24: 139-143. Koestner, A. 1987. EPA Scientific Advisory Committee Member, personal communication. Kohli, J. D., R. N. Khanna, B. N. Gupta, M. M. Dhar, J. S. Tandon, and K. P. Sircar. 1974. Absorption and excretion of 2,4-dichlorophenoxyacetic acid in man. Xenobiotica 4:97-100. MacMahon, B. 1986. Review of Hoar et al. and Related Literature. Response to EPA Purchase Order 6W-3948-NASA. Washington, DC: Hazard Evaluation Division. Mattsson, J. L., R. R. Albee, K. A. Johnson, and J. F. Quasi. 1986. Neurotoxicologic examination of rats dermally exposed to 2,4-d amine for three weeks. Neurobehavioral Toxicology and Teratology 8: 255-263. Mattsson, J. L., K. A. Johnson, and R. R. Albee. 1986. Lack of neuropathologic consequences of repeated dermal exposure to 2,4-dichlorophenoxyacetic acid in rats. Fund. Appl. Toxicol. 6: 175-181. Morgan, D. P. 1986. Review of Hoar et al. and Related Literature, September 15, 1986. Response to EPA. Washington, DC: Health Evaluation Division. Mullison, W. R. 1981. Public Concerns About the Herbicide 2,4-D. Proc. Annual Meeting Western Society of Weed Science 34:154-193. Mullison, W. R. 1986. An Interim Report Summarizing 2,4-D Toxicological Research, Sponsored by the Industry Task Force on 2,4-D Research Data and a Brief Review of 2,4-D Environmental Effects. Industry Task Force on 2,4-D Research Data. 7 pp. Washington, DC: 2,4-D Industrial Task Force. Mullison, W. R. 1987. Environmental fate of phenoxy herbicides in the environment. J. W. Biggar and J. N. Seiber, Eds. Agricultural Experiment Station, University of California-Davis: Division of Agriculture and Natural Resources; Publ. 3320, pp. 121-131. Nash, R. G., P. C. Kearney, J. C. Maitlen, C. R. Sell, and S. N. Fertig. 1982. Agricultural applicators, exposure to 2,4-dichlorophenoxyacetic acid. In J. R. Plimmer, Ed. Pesticide Residues and Exposure. A.C.S. Symposium Series 182, pp. 119-132. National Cancer Institute, Division of Cancer Prevention and Control. December 1986. 1986 Annual Cancer Statistics Review. Office of Pesticides Programs. 1980. 2,4-D Fact Sheet. Washington, DC: EPA. Pickle, L. W., T. J. Mason, N. Howard, R. Hoover, and J. F. Fraumeni. 1987. Atlas of U.S. Cancer Mortality Among Whites: 1950-1980. Bethesda, MD: National Cancer Institute. Pierce, N. E., A. H. Smith, J. K. Howard, R. A. Shcppard, H. J. Giles, and C. A. Teague. 1986. Non-Hodgkin's lymphoma and exposure to phenoxyherbicides, chlorophenols, fencing work and meat works employment: A case-control study. Brit. J. Ind. Med. 43:75-83. Riihimaki, V.,S. Asp, and S. Hernberg. 1982. Mortality of 2,4-dichlorophenoxyacetic acid herbicide applicators in Finland. Scand. J. Work Environ. Health 8:37^2. Sauerhoff, M. W., W. H. Braun, G. E. Blau, and J. E. LeBeau. 1976. The fate of 2,4-dichlorophenoxyacetic acid (2,4-D) following oral administration to man. Toxicol. and Appld. Pharmacd. 37:136137. Singer, R. M., M. Moses, J. Valciukas, R. Lillis, and I. J. Selikoff. 1982. Nerve conduction velocity studies of workers employed in the manufacture of phenoxy herbicides. Environ. Res. 29:297-311. Smith, A. H., N. E. Pcarce, D. O. Fisher, H. J. Giles, C. A. Teague, and J.K.Howard. 1984. Soft tissue sarcomas and exposure to phenoxyherbicides and chlorophenols in New Zealand. J. National Cancer Inst. 73:1111-1117. �16 Thompson, D. G., O. R. Stephenson, and M. K. Sears. 1986. Persistence, distribution and dislodgeable residues of 2,4-D following its application to turfgrass. Pestic.Sci. 15:353-360. Toyoshima, E., R. F. Moyer, S. R. Max, and C. Eccles. 1985. 2,4dichlorophenoxyacetic acid (2,4-D) Does not cause polyneuropathy in the rat. Journ. Neuro. Sci. 70: 225-229. Wagner, S. L. 1983. pp. 153-197. Clinical Toxicology of Agricultural Chemicals. New Jersey: Noyes Data Corp. Wiklund, K. and L. E. Halm. 1986. Soft tissue sarcoma risk in Swedish agricultural and forestry workers. J. Nat'l. Cancer Inst. 76:229234. Wolfe, W. H., G. D. Lathrop, R. A. Albanese, and P. M. Moynahan. 1985. Epidemiologic investigation of health effects in Air Force personnel following exposure to herbicides and associated dioxins. Chemosphere 14: 707-716. Woods, J. A., L. Polissar, R. K. Severson, L. S. Heuser, and B. G. Kulander. 1987. Soft tissue sarcoma and non-Hodgkin's lymphoma in relation to phenoxyherbicide and chlorinated phenol exposure in Western Washington. J. National Cancer Inst. 78:899-910. World Health Organization. 1984. 2,4-dichlorophenoxyacetic acid (2,4-D). Environmental Health Criteria, 29. Yeary, R. A. 1986. Urinary excretion of 2,4-D in commercial lawn specialists. AppliedInd. Hygiene 1:119-121. World Health Organization. 1984. 2,4-dichlorophenoxyacetic Acid 2,4-D). Environmental Health Criteria, 29. Yeary, R. A. 1986. Urinary excretion of 2,4-D in commercial lawn specialists. Applied Ind. Hygiene 1-119-121. � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Alvin L. Young Collection on Agent Orange Description An account of the resource <p style="margin-top: -1em; line-height: 1.2em;">The Alvin L. Young Collection on Agent Orange comprises 120 linear feet and spans the late 1800s to 2005; however, the bulk of the coverage is from the 1960s to the 1980s and there are many undated items. The collection was donated to Special Collections of the National Agricultural Library in 1985 by Dr. Alvin L. Young (1942- ). Dr. Young developed the collection as he conducted extensive research on the military defoliant Agent Orange. The collection is in good condition and includes letters, memoranda, books, reports, press releases, journal and newspaper clippings, field logs and notebooks, newsletters, maps, booklets and pamphlets, photographs, memorabilia, and audiotapes of an interview with Dr. Young.</p> <p>For more about this collection, <a href="/exhibits/speccoll/exhibits/show/alvin-l--young-collection-on-a">view the Agent Orange Exhibit.</a></p> Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Box The box containing the original item. 054 Folder The folder containing the original item. 1442 Series The series number of the original item. Series III Subseries II Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Source A related resource from which the described resource is derived Comments from CAST Date A point or period of time associated with an event in the lifecycle of the resource 1987-12-01 Title A name given to the resource Perspectives on the Safety of 2,4-D Subject The topic of the resource animal studies cancer risk assessment human exposure ao_seriesIII Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Alvin L. Young Collection on Agent Orange Description An account of the resource <p style="margin-top: -1em; line-height: 1.2em;">The Alvin L. Young Collection on Agent Orange comprises 120 linear feet and spans the late 1800s to 2005; however, the bulk of the coverage is from the 1960s to the 1980s and there are many undated items. The collection was donated to Special Collections of the National Agricultural Library in 1985 by Dr. Alvin L. Young (1942- ). Dr. Young developed the collection as he conducted extensive research on the military defoliant Agent Orange. The collection is in good condition and includes letters, memoranda, books, reports, press releases, journal and newspaper clippings, field logs and notebooks, newsletters, maps, booklets and pamphlets, photographs, memorabilia, and audiotapes of an interview with Dr. Young.</p> <p>For more about this collection, <a href="/exhibits/speccoll/exhibits/show/alvin-l--young-collection-on-a">view the Agent Orange Exhibit.</a></p> Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Box The box containing the original item. 029 Folder The folder containing the original item. 0482 Series The series number of the original item. Series III Subseries I Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Creator An entity primarily responsible for making the resource Belova, R. S. L. A. Sokolova Source A related resource from which the described resource is derived Gigienai Sanitariya Date A point or period of time associated with an event in the lifecycle of the resource 1971 Title A name given to the resource Toxicological Evaluation of the Herbicide 2,4-D-Butyric Acid From the Standpoint of Food Hygiene Subject The topic of the resource animal studies dioxin health effects ao_seriesIII https://www.nal.usda.gov/exhibits/speccoll/files/original/711ac6420f9aff7f3d5a95b56850972a.pdf 74d315fb0c3923814c0c67e4f70b5f20 PDF Text Text °1761 Item ID Number Author CorpOratB Author Center for Environmental Health, CDC ROpOrt/ArtiClO TltlO Typescript: Detailed Responses to Subcommittee Questions on Dioxin, for the Record, September 1983 Journal/Book Title Year °000 Month/Day Color O Number of Imaoes 31 DOSGTlptOU NotflS Includes a memorandum from Edward N. Brandt to PHS Agency Heads introducing the report. Monday, June 11, 2001 Page 1762 of 1793 �0 STS- 1 0 �Public health Ssivice •'.' DEPARTMENT. OF HEALTH & HUMAN SERVICES Date •v*:-Tr~r: vTi";- • v' •-. ; ^ :y : :-:^^ ,11 1983 From ' -'."V '" ''.'' •'•'.'.''•• ' • • ' " , . -.Assistant Secretary for Health Subject •••i)'. 1 .'- : ••.»'*- ' ; ' ~ ' - -'-:-'•'•••;'.' ' ''•••''•'••• 1 '• •'• • .;-;% PHS Views on Dioxin • • • ' - . • " ' , . ,: ;(.-'«v,:^.1- ."'-,{}"- •'•.• "•'."'X 'i !; . : • : • • ' • _ ' ; i •:._'..' ' '"•• -| '"..•' v ' ; TO '\-': ^-]-^'"±^\:J^: ;-:•: • • . • • : • ; • ' . -, •;. . PHS Agency.Heads .. • .'-. . . , • • ' •!.. OASH Staff Office Directors, : ; ,-...• ;O'.Attached please find an updated copy of the PHS views on' dioxin. It reflects'/:. •;.;''all,"of,the .scientist?s""-vle\ta"i and will be updated periodically. :;.. • ;;.//(;^: ; ' :.V^ : ; '' ':;"-'f:iv'-'''''•''-''• ''''••" '''''•''& t.''f-^'-\''i'i^.':-'--''~fi ''•'•'.• ' v ^''•'^Shouid^'you ' ""• ''•-',- :':''.•*: .'£1'!fr\' I will be pleased to 'receive them.•&££-**;?i : ^;-J'Than!<''y6u^^ • ; :• |.- -:]&K^iMi^&i&^^ •' ':,«>'•:. .'.';., M""--;'--'.^.** •':•,•..,./...••;.¥•.,", pj'.'-" : >'«.«?•' I " A ' ! ' " /*^ w«i<V * •1 r'.r?K : , . - r :?; i:-. ' " --•• "' • •• : '*i ' ; - . - • - . ,' : -.''. . ' s ;-,:•,.-•.^.v'-"-iW? ; 'f- J -'^• "• ,'."" .-•-.' ')"" ••.!''•' •'•[•> •-'^.••;-i>.^ti' !•. • ''«...j •'{••'. • • ' • : • • • •'. ' •- "• ••:'•-. ..-"• 'if-~ '!f; j-s *'•"••,•:'• • • • . ; • ' ' • • • ' >~,. .'-. •i ; - - . 7 !...i^ ,-••-.•.•!* :'.'S.::•.¥••:?*•&.•••'&.'• . .. . ' . 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' . jsufficiently," 2) sufficient time 'has . not. elapsed between-th;e;^^i;M-; ; : : v ; • •--••^'•• <Y^^^ v-i;';^' ;^ v.v -4;;^H^BirfS^ ' x p o s ure ia n d - theQitucly fb'r--"dise'aise. d e v e l o p m e n t , 3) 'a .'population; Jtocj; smail^;fpr; : re >:r.^\^^f»^f»;i^i'^1;^^^^^^ •-"•":- ^^^^j^^Vy^^'t^^^c^r^^'T'z^jL--' i-j'i i'^-^^-jv-^-—- ••'» wi,'^'? «•<•-:>«iv-*-^u'i«"=.i'-i-ri^-iVvi-.-v ne v ; ami ria t io nontamihat'iph 6 f;: t H e " ' c brnrner ci a I'-* p r o d u c't' wi t h d i o x i n'••.', T n e: ."c a s e c o'n t irp 1 \• s t'ti d Te s • .,,. • . '>,V •/• ^y, "•K-^^.iiA:^;^3);;::':^^r:^:^ ^Wr •• • '^••^•-•1 ^^i;^ ;^ ^y:;-''^:""'^-^; :'. li^'i.'u^r^''5 >s^'.--ij:j^ t?'i'l'i.':'::_ij2.'-'^;X j"l'iL''''i'~'i.'r-ii*. J''- : l'"'-K-4 Jr ^n <4'^ U'/^Ur.U'x"-".i U, 11 -'^^ *-ii'-''-'-.'Jr1 ;•'??; n elude: f ' ' ' *. 'V oft; erbicidesi-^ h e n o x y.a c e t i c' a c i ch ( . • LI" .** J,'l "<-*. '.' • Jl i ' T ' 0 80 . .•ijl«"W.'--. i;*-V.*r .' Rational cieatHj. raUs; ;for::men:Cage;d ^O/ ..".^.^'^:l:' ; . r "---'•(.-' •••'•y-''- : J'-f'"'Vi/;.-iv'i,. : '-"'. : --'.:-'^t'-:"*J -^•^-^v::s^'-'ao n l y " 0 . 0 7 % o f d'eathViJoijld : h a u e been ^expected . ; ; R^cenUy/;:anot|vepg|Jg • ' '*:•: • - : .$$ •-:;:-r^-^ -p^i:-. •.il^ife^fSi^H:^;!.-^ ?^4;/;!|i;;-.-' h:-' ^ T^ ^:^^:^v;V^fcf^fe^^-a^:^ srson. on^in c^'of' &iS'^plur^ip^^ :;^-,- ^^-^-;Sf.^a^"'^c^f&i^»^l^ ' ' ' - ' V •' • '>>' ;•;"' - ",'/ • ' ! • ! ' i';.; :.:i.'"v ;.• "'•.'•.?•'• :'..^_' '"'; •:''-'-• •' .: ••"- j" I ' • ' • • • " . ' ' ' • ' ' • ' ' • ' - 1 ' ' •{•''•'' ' • • - : • ' . ' ."'^'•"•"r-.V'j:-"'"^" �•^ •• -•> ' :•...•' ' . ,~ . -t V. : .•:," ,.- ; ;»••<".''•..-•"••"•-•....'.•,..'•' •'••:'-\~! i>-.'*•''ii .. ••••'.• .-.-;-v;/Ku-l-i.-T" ::r'--.J-' '' "(.-^, .jorkers.'. .jo r k e r s:. •i'-i^&- •: r;;;: J-I^/.':--': (Reggi'ani, :,.!?£ ne ! problem with^all'of 'these'' studies ;;.including;re^ ne 'i:-'.*-i ' J! v:. '-'-'- ''>- '.'-''S-;:. '.;''-' >«'c:T.K T'.-' --j.i-.-' 'i' '. ''•' ' • • • • ' ' J'v' - *1 • •-;:!-!4,«*-.j;-:4:!-^'.-'^ :•' -ij i^-^-'i'^s;..-- --. . - .<"•' -.-. •",-•;.-:;.• -*••-•'•=• :.:Y.;^^:"-* •••.:;" :«--V' -• :.. Vi^'V '-•:•- >'-i4 J,.*v Si'.'-J?:A:4 ^V ' ..-> ^^^^ ;:'•Jt^-^:•:l^:«v^i•*^^^^tft: that no 'expos tire .data" are: auailable:, In situations where, no systemic/ health/: - *. '' '•• »'. / *i * . '• v : i t" V • ; > " ' " ' ' ' *• r ''.•'! >1 ' ./'•' V '/» j^' vi i: : '"-•• ' '""* • I " ' 1 '' • '' •' •' ' " •••'''• ' ', ' ' T'I , '• ' : »' ! ', • ! - ' • . , '• -' ''" • • ' : - • ^^,. - f *V' . .'7* '. ;T* r ."•* -jkij-''' - ^-^r^' f*"V- ^ffects-'uiere" observed", '•'"absorption /of TCDD ': may ' have, been minimaiv^rjnon^xi^n: r+,-r-;~;~V!, c^:-&&&W $\f ?'*$&' Q'X* '!£* -V. r-y"::-::"---"- ! '•• i: •V-"'r^:^v-:^^^^^3^^ - or J n s t a n c e !; 'it h e h"iV6es't'-sbil,ievel in'Zone : A in S e v e s o /close .to::; thai factory - - instance^ = <: ; ; ; ; ; : ; •••.••••,-.:--••.-.• j- • i-^.^--'-A--t^.;';' i-r::-^ -?' . ^-i'"^ • -[':-;..""•.'.••: . . " ; - - . - ; '•- - v " • •.. ^V'r ^?. ~ -> • .:." Si-» ••• .:*-;:/j-^v-Wf-'--^---* -y : : ! :^ r:^^^-^ ^ ^^^,^i^ :^^^ •-•-/.^i--^t.^-'-i^,^-t-^'i^^ '. > '•*. jas ; 5 5 ' ; -legetation )f ;he uegetation.-was';>emo^d^early l^moreover; peoplejin ;the>rea cjose to^^he^: - - -: ' - ' ' - - : i - : •' • *?.'.'..'.-: ['• .. - • ;-.':^^u ' ;;i-^;'v-:' • '•-, &\'£^-:&Ui&%& • C-s f :.i,H,:t. ': ,-=••;^7^?:' ,^>>;r.:i -•^--^•if^^;K ivi"^:r-::' '"\ ^^ ' "^S'^^M^^^f^^- ^iWr^- «R;; �' -6-.: ;he s t u d i e s haue;'>'houjri';;that dioxin .''causes '"V M u l t i t u d e of. effects and;; that^it^'rnay^-: iffect''diff'^renV:'bVgan*. systems';'in|;differment- species of;*animals|.a^though^the-';£; :hymus'-is" affe^tid^iri^all '";sj5ecies^'testedi ',' Jhe:' mechaniyjn^lopacjt^orj^Qf^ Is hot;''well::;und^^ significant find|figs^liayef0en.^^cj^ ^ I& l ^ ^ ' J: )ind •a/,\recep't4r^'P' y rot6^ ^n.40,?^^'M^n'^y.-Tt^ •i ^d nay jome orqanic v c'bmppunds' into;-f qr'ms" which 'can ;: later: iritieract lwithyfjv;^^^^^ 1 ^^'•'- ^. 's:S--;-^VA's^::^! •••'^.iV.^f^^i'-1' K - - •.•"-•.;'!':':' -v- : .'-'.'"- ^"V ; .•.?•^''':• ;:'B•:•:i.v v :^^!^ ; il'^ -,^ �-7- P e r h a p s b e c a u s e . o f t h i s ' m e c h a n i s m o f a c t i o n , t h e toxic" e f f e c t s ; of''dio.xin nay be d e l a y e d , • In most small l a b o r a t o r y animals g i v e n , a lethal 'single; dose •;: -f dioxin/, ^the '"median "time .'to., . d e a t h is 2-3 weeks; For larger.' 'domestic';'•:.>-'^;T animals, dogs,;Xrid..monkeys/ A ; ,th.e; m e d i a n time \is_longer^rMany tpjxiVj,''coni^p.Unc?svK ; u c h a s';. n Ic o 'i i n e, / : c y a n i d e V^'.'a rid : bo t iii 1i n urn'" to x i n, '•' are f r a p i d 1 y.^me t a b'oilii ed^^Slpf' •media ted''.immune. Yep;on;seV; v is;:;toxic;' to .the;' l i v e r , ;a'hjd^causes^ r, ..have 'only' V .;" !:•-*•:.-••.:..:•:.• ;\--v.^.'V. ; ,'i-Vf in • rats : a• n•••:••* f 'micey^.;^•'.;j•-|v^:v^-.^^:1i.;-':-ir'-T^^S •bee'n co*nduct ed *i'"''i. ' • • • » • ••-•• '• d -;'i.. .• "' .,.;.,-•,,. .j.i.^^y.-: 't--.-- •'•• ,<'•.:-'•'•'.•• '• -H"- '• "-i"" .'•'<:'* 1 • tr,~'-f' "!;'»•- '- '- • . ^ . . ' « , A ; ! . . . •;"?.-•••..;•-.. ;;,r--->. [ f.-,*.-. .•!;•'.•••:••••*•- ,',.' ^ w'. ,-. • : - . • - . - , • ; < • ,: ••- . ...; ;.. *- ;-;.i ..f i-;,.-.:-. : :"^4r a'v ,-;';•-•-. ," i:.'^-^^-^ -: r-.v^l|^MI^S^^s:S^:^M®I^^IW Kociba; : et al^Xi^ 78 !) n^R 0 ^^?^; si'.5^110'^ i ' n ' w h i c h ^ groups of -50/male^aricr."BO;;: ; 1 emale ;Spr4gue-pa^leyJrats^t§Rar were fecJ.idiets: .con-taining, 22,-)f 08, arid 2,193 ng/kg"Cna"riogram/^ ^This' ; .fs^equiyalent- .t*q;>-^'[, aily doses t "of. O . O O l V ,0/bi;;/.ancl. 0 , 1 ' ug TCDD/kg bui (micr.ogram TCDD/,kilogr^m;.%:, ody L )T:" 'The.'" controls v'c brisis t e d ' of 86 male and ' 86 'female" rat's'y'Hr^Numerpus' .^;".-:.;.-xi;?v-i-:-.:^:;>- : r^'^^^^^r--!;..:,.-:;i •• : . ;:-;'• • : ; .!: '.:•:•' .-.;-.,;;'•:.'-:':• .•-,-.. •^^^••''\:?'^^.^^ d^;/^vs>"-- '' - ';: ? :.^ ; -^i;V-i;' ••;.-', , .--' . s.-V--'-v,; .. • :-;-^-:-^-.!-'^-f--./ V^e^^^^-^'^^ ;^r;--fv^^^^,--:,,:-,;: .o;,-^,-^:^,.,.; : • ; - . • - ; . : ,' *: :.. . > } , - j--; V. ' .•« /;.:V ^- ;/.:.,-; XW;. $..; : : �-8r. .oxicolbgic."effects' "were o b s e r v e d at 0.1 ug dioxin/kg bw/d ( d a y ) , including-; V n c r e a s e d . rnp.rtality / ' d e c r e a s e d body weight gain, d e p r e s s e d hemat'plogical;,;;V//.. arameter's j l.in.crs'a'sed urine levels of pprphyrins ', 'and" rnbrphological • change's"; i ; £l ft 2 4- *1 f» T * * r r i * ^ ^ * l * s " * ' ^ >>-J"v* X" X" 1*1 *i **» 5» J* /s w* i» s - • " tSK\r4 iiia^c^iilstfc** 4- "» j* ** i i j*» ** . i i l i n v * r f S - " / > t N r » r t w » i i r f ^ ^ « J - ' ' - « k A."" *J ^'.i.' » —i'^L " * *s : CDD/kg "bw/,d..vf.pr.;< one.-.'iv* -x-.'-"_-. year; . • : • >:T.,,-':' .'-'•i.V.."••'• "Av'«-:v:i : . /The' ; inclderiVe/of liver/, tumors' was /significantly ^Increased^inVthe^^^F ;-^*&3&^ -->$s^^ .7-ug-dioxin/kg-bw/d.- group-"- (48% tumor incidence) compa'red. with = that: of."•tn'e"^--f : ; .-'•" -•• •'vVRrf-><>^;v:^v.;::"-:^ vVvA-fci?;^-v.^.r;;\f.^:;. • y.r;'-;-:;.-:^ :..\-:v.. '/•: •';.' .•":;;":;i ';.!;^-.t.. " - l^^-'f^^^.^--^-; ontrol group^/ClS^l^urnpr^^incid^ '.y, The incidence pf:^liver tumpVs.^oBs';^ Tiue' hese animals'did : not ; surviu long enough for, tumors to'. 'develop. "".'This study",' v ^ •>«•;: ' • ; : ^ . ^ . .-.-;;• :; ^;.::- '-i,:. •. ••;,- ' " • • • ;•.•;•••; '•'?•/•;?.•••: '•;'•.•,.-•. ';"\"-''^---:v'^.f / r:-:;;' uggested that/TCDD^was carcinogenic at 0.7 ug/kg/d . '• J'|v=;V .?- ": ' •;••.' ••;-V'"' •v'ik-^P?-'rcinogenic at' 0\ 7 - - •':!""--'' •• • • - - " ' ' * ^ : - ' " • ' ' ' ' ' ':'' ' ; The National;,Tpxicpiogy/Program (NTP. 1982) .also conducted... carcinogenicity tudies .in '•„••=••• ••;.••..-'.;.'mice! •• brai""administrati6h of --j-i^,:-.-"^.- •.•':*v....--.-i-:.--^-.-!1» .-' -'. -•. •> •*-*.>••-«„-- ?;.--V, rats 'and .--i-. --':''•-•»•:'•!««•,-•;•.;..•.•.•"• j » <-•-•-•• -v-.-;-"-"I; •!•'-••'•• dibxin "Was investigated r in -.: •'. ' ' •'.---:,..'• .':.••••'.'. 'w-v "'-,•'•;• ''••„.'.-;.' yV-i^i^-V.1. *•<*'< '-:.'':.>", J •'••:"- "•'••.•*' ".:•• '.•'••V-1'"1 : :' '^'.': ;? -^ -V'¥' i'i"-:--""~vj T" v:-::^"V ''•' -•:.' '•'- • V^''*--^;'"' ';5 '•'' roups /of 50''male ';and';''5p' female' Osborne-Mendel. rats'; ancS;/50 male!;, B6C3FltmTcV;/; . o.oi, 0.65i;';^or';^/5;^ g / k g / w k ) /!./.. Under" the.: conditions /'of it his Vbioas s a y , 'dipxin.was carcindgeriici'for �•' . . ' • ' , .. *-9— • • : - •'"•' r'"' ""'• - • • "' > o t h O s b o r n e - M e n d e l rats and. B 6 C 3 F 1 m i c e , p r o d u c i n g t u m o r s of the liver arid' ' • " .hyroid. - - i _ .- -" I n ' a d d i t i o n , t h e ' c a r c i n o g e n i c i t y of d e r m a l a p p l i c a t i o n s of an.':.TVJ'-.'•• .'.: _' : ._ ; J .. J _-"i'"L i f - .1 _• ^ ':. *•'.. '"'L :. .-1 •-• » -i i- - < i- '. " - i _• ._ .'. - A igat'edV^-Simil^ i ->'.'_ 1 /•' ^'/^''-li:' 1 . i " _ " . '".' ' ' i ' ' _ " L .•;.""'•; one apjaii'catioriL.-.o^'-BQ^u'g'^vf^'l imethylb'enzanth'ra.'cene*' ( p M B A ) J ' i a : a'cetone , 1. wk r before J: ---"-•'- '•-:->'-; '^-i"--—•-i-^-'-- i j- . i-I ~ r ~ : ~~ dioxin-'uias .sdminisjte^ed ' . -.'" '• • ffi,''-.'''•• '•• '.n',:.'': '•.-:•** ••••' -.ri-'.!--..-! •},"•'%'•'."v"; .--\.!'-' ' ~ '.' -'v!;.;< •':'••':'' : .',' • •,-""'. _ -* /* '.J '•' » 'V ' i j -"•-'.. ' i , - ••*•' '"*•«* - . : .> ;<• , • . . ..^ . -'-.. . i » . . - . • ' • . • : ;;-V^--':,'-:n:';iv--.-'::-;i^,.-'!-:-:K'4/';j^1^;- •'••••;,•'•.;C' : " - ; '•• r ^ { • " • ^ , 'f>ma1 pi? ' rr-»r'<a-i upri O O O V " i j a (it nyi n v ^nbl -i r a f T nri^'.V *• '""•'',-")- '" • •'•'''» < / ••- t-- '"•* .•--i - ""* »-j " 'V-.-....-, he ir In -:..-•>;.;• >.:,;. ^ ^ ^ ^;q ignif.icantlyVdi ' . ';;./; ^^.i^,: he controls"',.'' : ^.^/;U *i v'••:: --^'T-H;lH:: i :.r- /:i';; . v , . - ' ; . '--'•,'..',- r '!, '... :^JC^: ; -v;i:^T -'. :.::^ ;•••;/:••'•'•'•"-' • : --,-'):?':••'-, ••}• ''-.: - *i>v''-riv'^>.^" ' ? ^-Vv v tv.tv':'v . :/'•••' •'••'••-.Vi.';/-;•'• ;•. L^iJt^^v.^rj;_.;-w^y;/"5^v-':"-f v ' : It is' : nbt " y e t : ' k n o w n whethVr 'dioxin is both. a. promoter' 'and/: ari:"initia'i:or;-'.' ;,. .•; .;.*.,.; • *:,.;;:V :.V.., M"^r^;-;;^\ ":;T;i-, / ,,;;: .y:.•. • ,'•.',•' -•;-.., j-v ; i - > • v.'!^. •!r^':: ;^v^-^ ^^.>: f cancer/"; and;';^jr^Do : th,r w^ predbmina^tes•;'.J Poland ^et-'al.;.;;^:; 1982)^have-^ecehtly "preyerited^ey^ /J : dioxiiY jirp^tes^tumoj:^^ :; ^ RS/j Hairless ' mice; •''>ito¥: eValV (1980) '.have "shown dipxiriVto .iDe" a^ .potent; •>:; ;1 -i .'',-xv/.^; i:£. - ''• ^.-" ':.-' - ^;%:> :-^nOiS^-';: '": ; .;r''x'-' : -:J'^'. :;:i-;;:- -.^' ^f^i^v'^'^^V^'^^i^fv^'y^ : : 1 urnor promofir" in^a' two-s£a'gV' "rriociel fof care indigene's is '.in;;.rat liue'r..'^.. 'V'-v ' ^ '-v'T-'- . . ' ' V ' ' " - ' - ' • * : : ; i'' i ~ !; ; ' •" •' '• •• ; -'.,••••'-' . > - " ' - J . '• ' '., " , . ' • ' . ' " • ' . - , ^"0 ' • "- ^ • ' » * ' ^ J ' ,' ' "'-" - : ' ' . •; » • " - ' - " • , ' ' ' ( " " ' ' . - " - �•10- The guinea"pig 1 s immune system is extremely sensitive.to.dibxin ,• Weakly' oc <:> C df d.ri ."no rH r>Vi n / l / r t hi it Pr\v*'- ft •' N I A O (/ c r<e>rn*e>ccorl +-fno 'rte>T a i/ li'rl ' I-. u ri a *•» c-a ri o -!"i."J Ti J 1; • ose's of l t ug/k'g- bw in. rhesus' monkeys ..; Thus, far,' a, no,-pbseruable-effect:'''1's.ge: •'";': >•; '-'••: •;:>^--j;>f-^'1'.' ':^T •:•' ": ;:^^-'^i'.\|^r':iK';":: ';!..':'.:' "^i •:" •• • '••'-'•^ "'"•"'••'0 ••"";,••:-^''^^-^^'^^:B n re pcpduct'JyV'.'6 tit comes i'JT^the;; rheVu's'' monkey has'' not Been'; Reported;' 'nor.^haO'Q": g-terrri' \].-?\-;,:'•• '.•-.'». •"•"-•'•!'•'•"'.'''. •.•-•'J'-';-.'-^ ;•.'•-.-' •'"••• ;•'•,'•••• '";';' ;;•• '•''•'••.'>; .-'i' b'eeri ^conducted" toVt-^ ny long- ,;:.';<'-!' (s'e'yerall years) • or • multigeneration studies '-,-?'<---::;; ''.-.•..'•.'•;'•••>.-•*'•• ..'S ••:•;.•...•••"••''.-' etermine .cl'" ihrpniVJiealth ;effects,-in --the more sensitiyV.species .•^-C'.r'^'^^rii^vf;: Some health effects haue" been '.'observed in humans which also 'oc.cur.' in-.v :. xperirnental'tanimals,; including. c'hlqracne, liuer toxicity, including Pp'rphryij �•.utanea tarda/, (PCT)", an i n c r e a s e in s e r u m l i p i d s , and abonormal liver., f u n c t i o n ~ e s t s . ; ; HbweyerT.lt is not"."clear" whe'ther .other e f f e c t s o b s e r v e d in. anirnals.:;".:,. > c c u r in hu*manS:)\ :: ''"Recently/"a.7pqsyibie'.'asspciation between exposure'"•'to"'diqxiri'" • - •/ .-• y:^^:^§^^ £.-«.;?•: •':• ^;;'^,:/}-;;.:-.;'-. :';7..'-.,>S'--'..'---:;:'i::;-.' ^if^-'^-^^-.'S'^ ind phQnoxyl^ne^bi^ products', knci ah i n c r e a f eViri . mesen^c:.h:y1nal:;;;^t ..'•-'.•' '^Vll^Ha&i^ •:'-Tri'l-D:?::- -.'. :^.^-^-^:-/^V;;:;"^'V-^'-^Sr-:;i^'^ lermall'y^to/'di'^ ndmber;'pf:..e'piderpiolq^ ies- a n d ^ h e a l j t h - assessrrients'''',i'rii Kurriahsv.'haue g i u •eL---.:•,'.; negatiue''>e'sults-v.^5^^-^-^fH n , :--: -tv: .:.••;••> : ' --•-'• .•':...'.-;,•«-^-r •'•:--V^-^-';^^-.^:' , . •,---~.->--~:fi&:i.iy*~w-':v-iu^.-^ *•<-..••;•« - •-• . 1r •s&^&®W&*&£$%%^ ' • ems , r • • _ • • > • •• • *• ' , ' ' • ' , ' . • ; ( " . ' i - * - ! !:*.*'•*'" i - v •;:••(• •'•.£•--! ':l--;r-i'' • / ? • * • . • • . ; -,3' '•; ^'- — ,•- .' • ' • - • — . ' ' - : ^ s ^. •_ ••..- - -f-.f. ,;•>.•'. V) !: . -' Jl •-• ;•:•.';> jroblems associated with- epidemiologic 1 studies a f t e r .loto-level. exposure 1 ,.;-.-.-:.;;•.; ••.\;[:.^-ff^j$zj*^^ •^>^r^-'^^Ai: :-^/kr;v^/ BA I^L ^. [>v H xs m «•» '. !?i'w^ /s 'l' «-\ >* ^ • j ' s i M . ^ i t ^ r H ^ B ^ v M • • l*v ^s '** -^. i i ^* A '' JT^ J« i <t« l-i y««' J *^ J- +- *i /* t I I +- "^ j**i i> "*i t^'' m ^v r\ •* I I us. •? »*s »^ "' .. ' ' . '•'-'' • ' « - - . hes ; r J :xpps i t_ ..... _ . -. . , . . ... ^ .„-,,... , „......-..(,. . -t - ..... - , - - . . . . , - . - . . - . . . - . - , .-.n.. -- .. - t - - - , . , - . , . _______ ...... - ,,- "-{''- unction irit"pe'6pie;-.b"ec'aus8^Vxt"eh'siue-' baseline 'dataTf6K^'tKe7g"erieraiVpo''puia^i6n"on < : . . c\l^5^^mi:.;f;ji?^^K^^tr*:r;:--r< ^-(S:M;®%fr?;tfSe?s5;©|S?i5 o not j'exis t^.an^d. lpecau,se ^ small'! differiiences:; in immune,, function r would b'e^.'V.^r&i^V cult ifficult to -'prove ...;' Another"; example ,is that effect's on 'reproduction .after^;:: i ow-leyel exposure '.in. the' general .population, are difficult to detect/ since.;;; eyel ther 'confouniding'uariables^^sucH; as"^^^ ational ecreational drugs, and malnutrition,, outweigh the effects of .dioxin"/; .This" -;;"; i: ; :j f 1 1 ; •-•• • • • .' ••• ' • ••• •;' • •. •":'<•'•• '•-'••'•.•'! ; -;v '•' ': "?- ""' - . :.'.•;'•• ' • " • '-"'f. •".' . ' • • , • •-.• .• • • • ». ••• "';.,'..- '• '. .-, V • ' •' .'•'•' ' " '•^••• '.- •-' ld ould be .so',', .'simply be'cause- exppsure^.to chemicals s u c h , as. alcohol .is m u c h ' m o r ' r e u a l e n t and o'cVurs at. hig'h'er do'sage levels in the g e n e r a l population." </.•• ' - • ' - '•-••• ' ^ - --' . . . . . . - ' . • ; - > -' ' - - • • • ' ' • • B e c a u s e 7 "of - t h e s e limitations : !as far as the : general : population. is' : ..-.V:"-l;' . : - ^ ,;.• ^^v•^^.:H•^.^^;::;^^< l y'!:'V^-ji • ^,l•.'•: 'M -'^ v;v--"".: .".;. '\ •• "• ? ">;! - : 7:-;^V:^v^^-^v^oncerned, v worker;;' population extensiveiyrr.sin;.ce.';.th'ey sually hav|y higifer;"exposures ..^ ^Hbueuer,- 1 the", number;, of / w o r k e r s e><p'psed ; .,tp., \;;., : ioxin d u r i n g productlon'Vro.cesses .'.is ' relatiyel'y - '• '••'•:'.'••.'• ' '•'••''-*'—•! \- •"'••»'.' ' ' " ' ' f • ' ' • ; ' - ' . :' '~. ,."'' '' .' ' '•'.'•'•''•',''•'•1 ' ' ' ' -i' ", "•••'.£•'.:••':.'' ' • " ' " ' .' 'I* ' "• >"'*•'''. . ' - • ''' ' ' ' t •'.'.',- ''--. "' --':"!'"• -.;''" •^-''-.'- •"•• :; . "' ' '''' �ill industralized nations) and may not be large enough to show small changes.. Jiey are predominantly adult males/.and the literature gives no information"•'•' ibout the doses,.of, dip'xin ^these workers actually received, nor are the. report1 :lear on how thoroughly these workers were examined. "t - . - • ' " • ' • * ' • " - • " ' ' - '.' •', •*' ' '" ' •:*• •' ' !' ' ' • - ' i Furthermore, wo'men ancf .' ' • 'i. ' '• r •' - -' ' " . . " " • " ' • ' • ,-, fc . '-*J''•»'•••• v •,'•"*> "i « <. ;hild,ren, who make up a large portion of the general population, are not t '"" •eally represented in this group. The lack of definitive human da^ta dictates s ', > * • * ' ' ' '' -.hat animal data must be used to predict possible human health effects:' r r f> ' " ' ' t * I y « \* lowcver, some animal species are much more sensitive to, the"toxic effects of ^ • ' -' > . f 3 ' , ' " ^a jioxin than others. In rats in a 2-year feeding study, a daily dietary dose r r v v " *r, - \^ vT •"'*'''. ' ' * * A %Vi ^ ' ' r / \> - .)f 1 ng/kg bw/d has been reported as a no-observable or detectabUe } e'ffe'cjtj' level. On the ot'her hand, ^i/" monkeys are siuen a s^-n9^e d"ose of I'ug/kg.bV, :hey cease to reproduce normally '(Mc'Nulty/ 1^982) . ^Although 'the', V7"* ^''^ij!^ *,*' ::pidemiological data seem to suggest that humans are less sensitive than'* I x ** i , » *l ¥* * * • < 1 , , ^ f * t"" nonkeys, we do not know exactly how sensitive or resistant humans are.'* ^ v f Moreover, since the human population is heterogeneous some subpopulations 'may f * * s * •>e much more susceptible than others. In the absence of useful"human data, prudent public health policy '' i i lictates an assumption that,hunans could suffer effects similar to those "1 ' " ' observed in animals and that preventive public health policy must,be based"'on vail able ahimalf.dat'a-. �Question 2: •Jhat dioxi'n health e f f e c t s re's e a r c h is^cjjrrentlv underway 'and what .'Un.llit '.; ze 11 ij's about '_the:"njaVu re ;'£md: exte"nt"'of h Urnari health'_-E>rQb 1 emis' as : so'ciateci' &i±fi'V; . health^ette^tS4pjr^their: expo^sura.^tp^ftgent Orange»-;;;a The questipn^of'uihethe;r-'',the .'health of people who liye >r have lived'in';' areas ".con tamina ted' udth.^'aboVe ,'back ground" leu els "of dioxin '(e .g,' Times, B e a c h X / ' h a s ; JDeen ;'or.^ilt^be;.]af;fected by ' s u c h exposures £ ; , V ;'-\-y; '-^;'%}£?£ - • • - . , "i^*; ;-'^'•(:••/•'•;,'•;* : - . ; ' . ; • " • >'"vT--.V F.: : - —. * •', The -• ';•" -'*•'•.,.••• ••• -.••.•'.:.• • "<;.:•..,-• I •.• •'•••*. -\- »-- 'Vt .;-;-'-^-^:4:' ivl _ i • _ _ . _ L _ S- *• l _•S ,t .. ;. ,' ._• ; • . *•;,-•'•;.:.;.: ••"•« " • y - " •* .J'-_ "•* dioxin--* • ••-• ' '. '- -•""-. 7 i: ' ' •' ' '"V.; ^ ;' • S" •„ " ' i'.*. •- "'. * -•--'--' '. • • , =1"' . ' ' " 'V '•,'',"•."-'" ' : ' •• , • f • .".'.'-, ;;.'-""^ - * ~ : ?.: , ' j-1 -> '•" ' " ' • , "" ' .' "' ' ' �T h e s e "studies a r e c o n d u c t e d o r . f u n d e d b y ' t h e U . S . A i r F o r c e , t h e '.dmirdstratio'n,... a n d . The D e p a r t m e n t ; of : Health and H u m a n S e r u i c e s ( C e n t e r s for, d i s e a s e C o n t r o l / C e n t e r , for ^ E n v i r o n m e n t a l ; H e a l t h / N a t i o n a l I n s t i t u t e " of ,r',;;:;;:.:.""''l-;i ) c c u p a t i o n a l .SaTsty and Health',, ari'd: 'National Institutes^,for. Hea.ltH/NationaTiv'. '•; ••\v-'.\'!=r^:^-^;-.V^v"!:!;*'l.' 'V i-^/vv^:^i^l ; ^i •.: : ':^:---- ^"' :"-"':::iv.;^;";';/;;T^. : . /.^'^''^^.^f^,;; i n s t i t u t e of; E p O i r o n m e n t a l ; Health;.Sc.le • In .addition/.-.the; EnuironV^ntaX..^ em, wi;th;. all^of,; these^tuc^i^'sVis'.^that: \£he^ actual dose ; of ; ^dipx^n^tji^^^^i ::: ^~'*-Zli?-*?n^S idu&^^ce^yeQ^ >e po'ssibTQ^tQ''mfix .pe^ I .;•-;•• :^.^m^mmm^ 1 * 1 ' ;ho did • •""•" * I- - ' -' '-I- **'• _ • • * _ ' ...".•-'' y"a"rying : ^amounts 1 of^^ "dioxin :,'with': people--': • • l_.^-*L' * f''_'_^':^'1__-.*^'.*'_ _ ! _ * — . - • _ _'. . "1 —J j^ f*. ^ 'k^. •" L. ,— _[ —I .' . ^_. ^_ ';• ^* T—•.'-.' C! "*»'_•• _• ' f * •"• "-^ ••; " esults EI u els'"could'" preVent' "such ;j mis classification and .would at 'the ; same timo;' lood leuel "'.• :::/'V^•-:;;.{|-;vi.:V-•^•/r:2':::..-^^ '"^ "''^'iff' •!"•:; • ^:':\^"^.-''': \,^';i-'':V'^r'"''"^|'''"• .,'\-Vi'::i ':;i.-.;"^'••^"'•,^vy"> iue us s the easurements'would be'meaningless;., since the' last exposure would haOe;.occu.rrec ore than 13 years, ago and since; the general populatiprf-.is exposed. to. minute,, mounts of dioxin from uarious' sources. ; - T -'/ ' ' - ' ' ' • ' .j , • • , / • : '•.-.' • . '. . • i- " • • • ' . • : : • .;;';, : " ...-'•'•' ' • :;;•"/'''.•!' . • • ' ' . ' '- ' .- .''' . . - ' " * • • " ' ; ; ' • 'L • * ' S t u d y i n g the; population; 'at;-Times B e a c h , Missouri^:.'still d o e s ' n o t . ' g i u e u s nformation : about; low-level;';iife'time . : 'e'xpo'sure to dioxin/ Since" it ujculd,bs /; n e t h i c a l to a d m i n i s t e r dipxiri to-"h'Urnan'sT we"jTiust' rely Von ahlmal'-'studi'is's'-'tp-T^ �•;ake p r e d i i dictions'about the'toxic effects of dioxin. Similarly, it' would'not •ya u s e f u l to look^. for " "acute subclinical health effects..of dioxin-.in a ; •opulation" that .had its last, "exposure many years 'ago,, s u c h a's' some.'of, the y^-;v>. iroduction'.jjjcVrkejrsVJ'. 'Iri'su'sh^a population'; the analysis;-of morbidity^a^rid.^s^vlortality"' • data' 'w'buld' 'ibe' -mo• >re~~• •*f •'•.-'. i t;• f u. -l •;-•'':"••'&•• "t;-:'-. V:, ; ^,. -•;.;•; >•- • ••:-\rJ.^^^.i:\..^.:-#-~-?R^t^:^^& r u '. . . '..., ,',i " ' f ' '. * -• "''-"". -.' ' -."'' • " • . , " _ - ' * • • • ' i " ' /''•;.,": f".'"'•'•••'"""*, "*t """"-i.'i- i* f ! e ioxih!"ex'p"b^]j.fe^ ; in ;,Work'ars ; 'occUpatio'nally. 1 exRpss^'t.p::xi^^:^ ioxin^con.t'aminaVpcl * product's i.;^ In 1979 , CDC began^uiorJk,'*pn"X/'registhy . of ; 'uTsv-'' !< • • . ' "'•'• >^'?^^i-'?^'^'-;^r^^K^;v".::^::"?'v i 1 ;.'•:-.•!."*•" •'.-'i.-v/ ^::'^';^>:^7^;'/^^':i;-'^^'^-^ «•' >roductioh. r wprkers;.whp. were pptentially exposed,; to;..,dipxinr d u r i n g - the '^synthesis r formulatipn' of/substa.n'ces';'cphtaminate'd .'.UJith di.oxin^..^;Jh'e^'sub^anc^sVincluide u c h commonly " u s e d ' productsVas tri.cHldrop'henbl; 2 ' ] 4 , 5';rT;'•'•..'the herbicide which: i - , : !-.:':' \>-':Ft-j.i^$i;Z'i*&-.&^^ •as .'one comppnehV.'pf-'Agent; Orange'; ''a . ' " : -;;.' ''": '': V.':^ •:. >V ! l'X ' ,": ."..;:;; - : . V ^ V r - - . ; '.'.-.!:;v i - ;!.."'•': .'i' • • l;" ' :':. ^ i| : ^f.V' i. ' ,'^V> ;' : ;J:? 'V'': ^'"V^ ;'.": f-'". -" ; -' After .the CDC'registryVis; completed,' qurvfirst, research task,, will..b'ev tq - ; ' : , •;-Vi^'V.O;i=Vj?V-:';:i^A^ ompare^.th'^'^aus^es^of^ide&t^ '' l''l'^!':£:i'*'*';>'. ^^'^^'ii^^-ifc^vW , S. population,?., We exp'ec^t' to ' inclu'clet about 6 ,000 'wprK'e'rs'''in" ; -this J -;stuHy:;jv-:^G f July 1, .1983,: 5,000 have;: been: included in. the ' registry'."," Enrollment' will ''bs ornpleted by December of. 1983 ;' "'we plan to have all. information >elating r tb v v ; '"he status of these wp'rkerV.collected and analyzed by .March 1985"™uieli: b'efor.e he final -'result's", of ; CDC/ s 'Agent! Orange Epidemiology Stu'dy .will ^.be"'.availabie',; CDC is exploring'., pthsr/^uses; of: the w o r k e r r e g i s t r y > '.'including, u s e ' i n -• :'-, tudi.es of certain illne.sses and" 'problems 'wi'tK reproductibn- 1 'a'm6ng^e'xp / osed '•';' V �o e r s o n s ; . . D e c i s i o n s to' p r o c e e d with t h e s e k i n d s o f s t u d i e s d e p e n d on scientific, f e a s i b i l i t y and., .the a v a i l a b i l i t y of r e s o u r c e s , Since .mos.tof th wb r^e rV ". n c lud ed in .the; " CDC ; r e gi s try '.we re ^e x^'bV^^jCi- inq' "the !l?eViVd'Y9'4b^ ••* • - • • -. • • ' • . - .:.(•;• • •'•-• .,•'.:.. -'* • :' . ' . • . ' • • ' " * ' ' -v ' - . . ": i : -V i '* '." • : . ''!• • '•'• :."i? •' . - . "• .-«'.':"•.) .'.•; ..-'•• -''-I •• ••'*-• . •.'• • • l . ' oith long latency "periods^be ''.ab*l.e'_'to^ find, t h e m . :o ' e u a l u a t e ^ f he';>t^ait!i'';'Xt^ • : • ' ' ^r : ' ' • ''Workers: ha y«p^e.ire^ • • '_".••'• •-'.'.' v '..'..".•"•• T'.:.' ;;V«-'';'J,, i.',;:!., ';.':." -Vi^ .- .• • ;--' ",: '• '.'•'.'•; ' . ' • ' • • ''•, .".:•" ":. • • * '.'•j'.^'-'U.V.'^T'"".?'- : HoweJe^>y_we."_plan. i ^^ '>.er>prif at B-yeVr;; inte;rval;0g||:|^|gt|j ! ' '"'•' '''"- ' • • ' "- " • " ' ' ' ' 'reduction;'Rer>^ H'n'nal"-Tn'e'fVf uV*^' "'nf.'-'"p'rfuf^rinm^n^l' 'Meal f K Srn*'4rireV' YfJTTFHSV Ptii$>ri'e>>! -»^:"^i' acid herbicides and - c o n t a m i n a n t s ii.v.that registry is similar, to. CDCI.sv^rn^*^ l : - • - ' -••^•- ttv>*.-.;»^V^ •>:'••: - :;>••>: :^V¥--2-o; :. -^:\.ii^,v^^.-^^:^v^>r ' • • ..'•::;'- 'V^'V^Ci. .* •-:;'4=--. ,..?:;---.V-V;-;,-.;v}.S;(^.i,::;-i '.'•'.^•.tf-:-1. • : • . • •;. -'?-, • ^^ -'::,^ ;..•'i'i.r^^-rV;^^/;-? ^-Y-.'f ^;/.^.: December 198?';'. ; ,Dr:.,"fatrici^oiichar;^ on '.detail from ;CDC/NIOSH;'±-o-;IARC/V:^ : :c:^' ' ' ••,^rf:^%;°'^/^ ';/.^ •'?':•'-'.•' ' • • • ' . ' • • • . : ' - ' ••'^• : : -:-:.-< ; ;;.-- V> .V :;•':' :?'JU'' •":-•;: *?:•'• ;ompleted the.:feas ; ibility a s s e s s m e n t .for .this project.', , Cohorts frorr\ .mor^e-.thai •20 product! on ,f a c i 1 it i e s> t n r o u g h o'u t; E u r o p e" a n d A u s t r a l i'a "a n d N eui' Z e a i a ri d ' we r &' k ; : : r. - '::;*-^^^^:^.•«'^7.:•^^ '^•^^'•••^ •t•:~ ^:•,'J.• • rVv'-.'-j. ••:;..••/ ;'-^.;-.-v^.:;:;:;Vv^: yVi.^.-."- -^\'-•rS^V^^-i ;>^-^^ ; ; ; ; ; ••v-'.^^-i-^-^v^v^xn^^^^^ii^r.?^* ! i< - vs.'. -:p;' ;::> -•;:•;,•:: 'h..- ;rv-^-:.:':5: ;i-\, •• ".'.^>.' i^«/J-:;?yy:.^;^^i: : ••'''"" ted', to. ••determine- their" suitability for epiderniologic s t u d y , Now-th"a"t ''-"' :he feasibility" study; ;has\be>n ^completed; a joint l A R C / N I E H S meeting ,:has'";b3:en s c h e d u l e d , for mid-October" 19.83 'to'' bring together potential"; collaboraiior's^tp-;^ iecide"wheth ; er'to^ontinue; t h e ; project a n d t o . d e f i n e an'."action pis- ' ' ' ' ' • -''"-" 9 7 7 , cases 'of- s o f t - ti's'su^';,sarc6m"a were r e p o r t e d among\;Siue;dish'lumberj's.'cks~'uih �; ; ',: •". ' . -.;••. :";'- "-^V,';' •:/ . -17- had been exposed to phenoxy acid .herbicides. Thi s c l i n i c a l o b s e r v a t i o n . / l e d - , researche'rs in Sweden" to cpnduct^.two separate epiderniolocic case-control ;.v studies;'which; showed; increa,seci, risk.; pf. soft/tissue sarcoma.'. Later, K result;3v< gather the'"work/."hi stories'-; and ;patholbgic:: s p e c i m e n s for all s e u e n . ' c a s e s - i r ";- ; .:*^ :A$ e'v a u a e t h e . ; ' ' '^"^^ * '' ' ' ; ' ' ; ; r sarcoma •.cages' !.a'nd';-- to- f pcu's 7 medi cal /expertise''; on .the ' ques.tion: 'of: tji legitimacy of ...grouping di/ff erent ] types of, sarcomas .;;..:. '.-,*'. .' .;•-.;; ; : ' - ;'-•«;':•':; vC.^-^i'l'•' :':'-'/;i.H'-:'';-^^Vi;;'-:':|v^-^©^^ ;i i : ' ''••• -; . P- iy^iS,:|-^|| ^:^ . ;; We beiieye'/.trtat'^nfoymatlbn' 1 ^ • • ' • : ; ' ^ : ' ; ; :;, • ''^U ''•'l^'-;:.'':' 1 ' .^..'•''.'•'-^•'••.^ •^,;:";K^ /'!.''•> .•;'-V::/^l>!-:^':"-r'''7"'-!'"-.!';2^!\ ni^v^ as'sbciatipn between^ soft. tiss\ sarcoma i n jiumans^ancf e x p o s u r e - t o 'dioxin-contaminated p r o d u c t s is - . / • • • j r . ; ' : . ; accumulating.; I n t e r n a t i o n a l ^ s t u d i e s that fail to, c o n f i r m an association.' :: ';'-. , between soft t i s s u e 'sarcprna\in h u m a n s , and e x p o s u r e to d i p x i n - c o n t a m i n a t e d ' j : '• p r o d u c t s s u f f e r 'froV the; def icienci'es p r e u i o u s l y d e s c r i b e d ' o n page 3. •.'The..;.: : o n t r o u e r s y : o y e r 'this ;as'sociation is ongoing' w i t h i n t h e j s c i e n t i f i c community.' r or these " r e a s o n s ,' Curoful'.-apidemiolpcjic a n a l y s e s a'i?e ' ireeded. The .quest5 : on o in association, of s a r c o m a s ; and e x p o s u r e . t o p h e n o x y acids and chlorophenols Is :eing a d d r e s s e d in the C D C ' D i o x i n R e g i s t r y m o r t a l i t y s t u d y a n d . will be' "•"„;'"•'. a d d r e s s e d by the I A R C s t u d y . In a d d i t i o n , o t h e r s t u d i e s , s u c h as case •• . : . �-18- ontrol studies', are being proposed and conducted;. Epidemiologic.studies . li hese will further delineate any' association. • 1. . . -' - - ;.;'- A number of' case-controT studies : haue either been"propos'ed: or'started;-.-; ; ; ; f; : ; ; 7 >'./•'^ ^?^ X-;^•'^•.•c• ^ ' •>^:";'^^^•:^'•^^r•i: ••4^•• ^ L•; ••-•n. • ''••'' .- ' • ' • • ^ V - ^ - ^V'v^/ ^^;^--^"^ A N a t i o n a l C a n c sr..: Institute *'*<*T\ <_£'.._>,, will ••^..i.^if.^j.^: >.--•*-'>.•-r-i-.--^-..-^^-.-.1-.--. e r Institi 1 - L ~ "(NCI) 'study ..---in 'concentrate'" ph Voft^t'is.sVo" ,- ," • ' ,. ..'*" ' 'f • •"'• ~ '- •. '••*:;.' ' •; - '- * ." •. v ^.;.-^-;i:;^':i^.^-Vf/•:•;'•••;."•- :.;V-;'' :»^-^'-'•'' '•' -•'V:-'''-^-"''-'';;'':' •^^^'•^^'''•^••^''-i » fc. j* ' 3. ' v^. _r\ >J *J ih. «1- ^ . Ln'm *^ - 4^1 ^i I ! I In 'r* J_ ( X^ h*t A " —* 1>S • *•«» l-v y^i W^ ! «^ t^i 4V • * ^J J*.' ft >>' ^K <-i *T * J« L*i A. jm >-. '* * ". ' 1 ">! . The Armed.'Fprce's'/ In.'stitute "of. Pathologyl^and ;the .U^S^.^Ueteransv^x/;^^-!^^;;; ie ft d mi n i s t r a t i o a wi 11\ a Is o';s c o n d u c t:;; a "c a s e ~ c on tr o 1 , s u & y o f .s o f t. t i's .| s a r c prna s r;" Since': "t he s e.'." t u mo r s 'a'r e: r a r e", fmp s t p a t h o 1 o g i s t s " ,'d o'. n 61;: s e ev'm and.- ha'y.'e diff icul'ty.;iji':diagnosing ] tjVem,,'"." Hans ' Enzan'g'er, of .the: ftir;','For.c •'•'; • '••''. ^•*^<§:>^--1:;i&^:;.';l'i-:'t$.-^^^S^h^i^^^;'^--!:/''•/•' :-'-"" ':-''^':;^:-ill':V-;.;^l" ;-.lf^&.^#:&£&(&. . Institute^pf^Pathology ;.-;is"|n; expert ,;in. the' diagnosis; of^. these"; tumors;-'.aji has 'a"large ;'colle"ctio'n'..'frpm;;around !the country. .', These;, tumors 'uiili'form;, basis:; pf .the.' study'; '••'/': ';:' -:- 1 ;';,.•.•••' ,f ••.'.'-. '• ' ]' ' ' ''"'' '' '•'"-'•' ' •'•" *•-•"-"^' CDC has! proposed.;an. additional, study ;using the NCI's Suryeillance , ' . . i r . Epide'miolpgy 'En^ Result's;. (SEER) ^network.;: ; . ;. '^-,- ••-•. '<;: • • ' - :y .X:.'::,.:;;';,v :.:::-:-; �Other pertinent ongoing or proposed studies are listed below. CDC has been conducting an investigation, with support from the Veterans Adminis'tration and -the; Department of Defense, to determine" whether" 'v'r^irV- Vietnam'veteran's; haye a higher"risk of fathering 'children with birth'^l^" defect's. . Data . 'cpllectipnvis to be .completed by the, end of;,-1983 ,", ahcf'vtKe, J l • " ^ /, -i ; p r e l i m i n a r y a n a l y s i s is to be d o n e s h o r t l y a f t e r w a r d s . < > * i • , , " <• 'i _j . , v r r - -* !v .** • •" v. * ; ;.' " ^^ CDC has developed a proposal for the Veterans^Administration to* conduct f ^ < * i ' ^ ^ m ^"* *• large epidemiology study in Vietnam Veterans. Jfi> ' " i '' V i. - ^ - " >5 V >' i t The Veterarjs ^Administration is conducting a mortality study on "personnel ! , \ who served in the military during -the Vietnam war, V * . 4 J ** t * *i ' * The .Veterans Administration has also' propose'd a. study .of twins, only' one of whom'ser.v.ed .in "J -^--'-'•••";;•"•': *' - ' ' : ''•' : • • • • • • • ^:"!S:['J&^ .•,.: U.S.'.^ ; x V ; Air. * ^ .conducting ; ^ For..,ce.is The : • ; - • • • - - : •- .. ,.'•.-• • .^---, ; •:.-•... •:^^^:^•^^ ;;5X^:^?S^ a study ; vyv^^s- - who '^^f^^^S®.' -: .conducted/- • of personnel spray:' 'in yietnam—the."Ranch Hand Study." ' ' fing ' _-...,.. Some"results;.of this study •.,' Id should becbme.'.Vvailable, ..during!; 1983 . : iV mortality ., study of .'this 'group with only a very.rlimited number of death certificates, was negative. .• • CDC is'.conducting, preliminary studies in selected;Missouri populations which haue been'e'xposed: to dioxin-cohtaminated.'soil.' Some informationv c ; • .' :• "'•^v.'V'. •••'•"* ;:"^.; -•'.-•;-£•'.• ••• • ..';,-•; ;•'•'-•;/..'•.' •'.-: •'• • j'v. •• •• . •• '-. • .- • '..'•! -'' 'j • ' •. .•.' •'•".''' '•. "'V • ' '."'.'.•.*•'.","''• - ' " '••' from'these studies should, become auail.able by the'-'end o'f 19.83. '' ''.-"•",''•": �Q u e s t i o n 3: (hat additiojiajl r^ ' Animal'r e s ear c h ' nas' established t h a t , oioxin is'"very' toxic;> '-•• t'ha"V:;'it:;is^^ ha s' e s r )xi etotoxi c , " a n d . c a r c i K o g e n i c and that it impairs the celi-mediated;;iffirmjne^^ nse';;?-:'':.p'ioxi^^ respbns b u t , instea^; : ;isi-'aii vi^Purity^n^iV" .,"•". A'.'"'number'] of •X t " s ^s^in'. i tH'e^Uni^ed V^-t^ :ertain chlorinated;^ ain .•' Most :pf : \thisV;^ibxl f ^ StatesVlVaye^jple^ "> -? ^» \j 4 f\ »-i v\ • v ^'X *I T "i "** "• V «•> r\ m A" i . i K a 4- ''.", *l a t* o . r> i i n «i T ±* KT X 4~ l~i = ^ ^K» o d ^4 "! rs v *J rt ' A T 4-'!S /M »r^ l*i - ' '*•* *-.l^i"Jsi1' '^ -i •* : e 7 and'', bi pau ai ]Lab'iii ty.; of :Jdi^i n ' f^r om;;d if f e r e n t"; soils v.;';.e;i:t hej^fjp|r;fcfnanV^. Dr ani'mais'.'; 'iV-v-' (Wo"te':, ; . .'»•_•-,•;,'. i ' - •;(.•..!•• •••r./ .""---:v.-•-'-•,;,,:••!. .../-•, •-,'.••'".'.•,•,» j -n o••t 'j .yet> •:-" '•,.•=••.:: '-.!' .--•-- > ahimal ::; .'s'i:ud"ies ; 'b\ '"Re'cently: 'completed /.but'- ,'- ' repbKted .'' -.,:',v>i-V •,':•,;,, y \ j . •••-. r i" • •' :•:> '.!•••• .-'.••- '' • :"r*--'-t•' -£i : : v -^V:& V£?*>rJ-^ -he National foxicolo'gy . Prb'gr'a"m-."b'n: bioauailability.'of ..dibxin in ."cb'ntami'n'atbdT:JI ' J '-).:^t^^-£'^v^ 5 o il s', i n d i'c a t e •• h i g K ' 1 e u e Is?, of Vd i" o x i n, a re ; b'i'o a.y a il a b 1 e:' 'i n , two 'd i f f ere n t' types jf soil''.) ^Nv':";v;?;K-{^ft^:|.;-^:;p5:^^ : : ' •'":•"'' ^ ; "'- -' : '^ "'i'^-viX^"^.^'^'* To prpuide' answers: 'to/'the "qVestion "of.'whether hii'rian health "has1 bee.n^;1"'';;. effected by'.dioxin exposure we 'must 'do additional human'epidemiology •studies'', rhe most useful studies would be. those of.the highest e'xposure to, the largsst lumber of people for; the. longest" time," If those studios showed no affect", it jould be reasonable to assume', that! nothing .could be gained from studying ndiuiduals with lower. and:...shqr.ter' exposures;.".. If health effects are.';' :- .'; :': .dentified in. these "studies'/ ^Investigators', could lo'ok.J;or them .in;,1 e'ss. exocso: populations^"" •'.'•' -;.; ':'.:; ; .:' ••.'I}':-,''-/.'":-^' '1 :'•' '•- '" ''•• '['"'' • '. • ••. -"- -'-'v":': ;';'"• .,"• '.;;-", '••':':'•'•?'•=''.• r';"" .-:' �-21- For the health effects, data", to be most useful, investigators " should;,;/ <;s. jetermine ••"."•;'. ••'* '-.-•..: ?.•-.'•' .:.•-•.-. •:'• f burdens*'1V-:'. •*•';'.the study-^ . population.•-•••.•'*.•.•'•"' • ; -U••.'•./:-./;'.'--.^"~- / . • / -•/" dipxiiy'body '•',••;'*..':-: -';"» in. 'i-' .>."->-•" •"•.'••''•?• k •?;>•';;• •••-.•'•^ - '. < v>' .....", •' ;.' .<;.*"'' / /^•^^lii":'C-'--''\,"j ' '// '- - "' • ••'•••'•"•'•' ' '•-' '> '-—••".'"•'••- :' J '- : ""- •,*•'•.' ' .' .'•'•.:• ••1"..i '" "•'' " '..'•:""•'!.' . ' ''-''•"• :'-> '"••••:' :':"-"'-:- For this reason,,; the ratio .between dioxin leyels in blood ,and acfipose./'.': tissue should be ; determined ; -The methods for dioxin analysis in blood';and ''*.'•'-''* ;: ; ••" •'.•'A>-=."v- V':" - ' -? : ^ ^ " ; ^1 : - ^ - ,; v;'--^>v-:-^| = ^ V " 0 : - ^ ^ :r"'^v' adipose tissue; "need ,'t'b be. istandardized ,.. 'and appropriate; ..quality",.cp.ntr. pls~-; and:. 1 • • •':->•; .'•.•.•*-... -/•;•.••:,:/•••";;.' •"'-' •,i; ^U'VV':;tv,;."?'";':..iv .,;'-- ;> -,r •'.;'.: • ; •. •:';."'",''• * . . '--v -ir'. "•'.-•••''..•'r,.MV-;...=wi-.'.v^ >^VJ-/-^ '. -.-:f: ' '• •"-f^'-;'X' ••"• •/£-''.:'• •'"/"-.-•/:•' ';'i •:'•'.''',•'• •^'••:,'!v..1.'..".V.::.; .:: ••• • . . . . '.; •'•;;.,• ,..-:'-.-•!' •',;-'-•' V ' ' ^ ' ' ; ; .'.,'!.••"'' ; . - V - ^' ; ^u a 1 i t y , a. ss u^ran" c e!s ;;jie e d s" to .;,b e''^e s' t a b'li s h e'd ;•;/' _ For', s c re e ni'ng ' ^u r p p^s e s V.-' we ". h'q p chat .it. wi.lij'b'e^o^ : .'lel>el"s .: in -'blood ^^fit^ls^muii^xy easier a nd /|.lesS; ' ' " " to collect/ blood 'specimens t:Han"'_to obi:ain.;$ufg'icail ''traumatic"" "' ' remoyed t | ^ s i e | /-;3^^ ;£i^jv: The folloming IniF'Qr'iTi'afcon 1 "''relates; ' .the" Subcomrnit't'ee* s:: questions; 'reoa ' ' ' 1 " 'to " ''* ' DC's determination In a.lrVs'k£._as~se^ ,.animal/data' .and_ oiV an e'valua.ti'Qr of how'ind,lviclua:is:; c'arT be/exposed .ta'spil" and Contaminants ':ih soil, ...the/CDC/' estimated t'hat^ 1'ppb of dioxin" in a residential area u)ould/represent/a risk .cor human exposure'-'.'tb'/dioxin. This; assessment was based on a number^of .'"bast judgment" as sumptions"''for, "which definitive evidence is • not; available •; .' Some/c chese assumptions deal with the extrapolation from aniipal data.to. humans'and jjith judgments concerning tha" mode;.; and ^ degree of exposure./; . ;. . ^ ;•'•'';./•/•... This 'concentration' was'"calculated by^'considering houj much dirt .a..'to(.Jdlc'.i (child age 1-3 years).''miciiit.eat/how. much dirt, might be picked up by the ski; during such activities as Gardening, and how much dust.might be inhaled.. It was also cpnsiderocl that -V//V';/' / //'// \ /'^ •//•.%:: -•'.' '^--v; M'' .• -"'.V"''/ :'/^/- �-22- ;oddlers would only eat dirt for.a few years and that gardening would not ba : ^one on a da.ily basis, particularly in the winter. It was assumed that..if.'. th iioxin was bound to soil, absorption of dioxin from skin might be 1-10%";''from he intest'inal; t;Fa:ctv-'30%;:;v.and; from the lungs, 50%. / At 1 ppb. diqxih,'In'jiJieV'.v oil'(if the-dioxin was bWhdto soil), if a toddler ate 1 gram .of' dirt,''."got''! •ne gram of soil on his or her skin, and inhaled dust from the .area,, his./bh .,-j ier total dailyfdose ^uj'ouTcJI'be between 311-400 Vicogramsvp; If; I0\'grams-'of,'dirtiere ingested and .10; gYams 'of; dirt'made' contact', with the'';s'kin","'.th'e"'.'d'b's'V"of?•'-•*:" ( .' ['•£&^£&&;^*-'^ iiSfef'-':!^. -.li"^- -' • '•-. •:.;' - i '*•• !:.\: : -f •; -l^ /:';-^T' \%f^: •'.' ''^>. 4 Therefo.rei^oh^'af.bbdyV.w for a":..10-kg. (about. 22 ..Ibs;.")';-todd.ler/,- .he doses 'that'' could';befrece'iued.^ 3>.to 4-year.-, per iocT (ages ^:I/2^^.B... ^year?)';; ....p'uring . thJ.s -timef;;the;dq.5fe^ jserj^;-nit of body"weigjit' wouldi^gradually .:.dec'rfa"se,' since^'the; child '"gains':^wei^|ht.^-^' ihile\hand-moutl^ "activities.; decrease'"','-: The' dose for';'adults ' would .b'e'';iVss'-fonr"a g bw basis-'.;.-;.•.: ;: '••'']-•-..",vv;: The no obserVable"" effect leuel 'in 'rats is.1,000 picbgrams""psr kg"bui;v with i safety factor'of-'. 100, the" daily allowable doso would',be 10 picogram/kg bw • 'or humans for a lifetime. Additional safety factors should be : added ..because • if the effects .on reproduction in monkeys at dosage .leuels of. 1', 800 - : , : . '' • I cog r a m s / k g kg, ! because^dioxin causes cancer ;in"rodents, .and because .species^ ' -ary in s e!'nsitiyity.-::\:-Exposyre'would ns 'not', be for,2^ hour's; a day sOery^'day'/ and Ithough dioxin;is,extreinely persistent in soil,'soil leucls would"gradualiy f •.. �iiminish. If an a d u l t r e c e i v e d a daily d o s e of 4,000 p i c o g r a m s , his or her - lose on a kg- bw basis "would be — f ^ — o r . a b o u t 57 p i c o g r F , m s / k g / d . .If he o r . s h e -eceived ^OO-'picograms', ...the ' d o s e would, be 5 . 7 p i c o g r a r n s / k g / d . . "f Jhese : /cSos'sge';/. Levels are belouj^the no-obser.yable e f f e c t level in rats ;v houjever ^^they^ dojnp_.t Qlow a sufficient safety ;factor,. nor do.,they take .into a c c o u n t .the.' variation. In 'sensitivity ' between/ s'pecies^;; f : . : ;:--,i.; ;'/•'•".• :;V ' .- ; . ; .-.;.:'• vv^'^r^'--^'^'-^'^.^^:.'.:'^'^^-^^^ Levels; : 'b'el;ouj.i''p!Db' in;Vsoil.:'rnay .^be . f o u n d . in;;inany' areas.- of theVUnit^d .^V^N States' andVmayyTepfe^ Some of tK^;^ources' : ;pf'-lHV?e^^^ iioxins 'are^combystiojri.' and'^gelneral pollution due" to :us_e' i j j?f""chiorinated; phenol I . . _L'.. L J ii'jL. ".'«UU.'.'JL .' T O'yl'C.' ; ' " M^,t; - ' m i ' i ' ^ U n «^A»-.Tn= 4- 4-r\r\ -1C »I1»^^S>K^A h n l i l o 11 ftV "'•-'... r\fi '.:• 7T".,- The level of.:i"ppb is! not t o ' b e c o n s t r u e d as. a "safe" leuel;...houjsuer;;-it, .s a leuel .of - c o n c e r n , "developed1 f o r ' o n e ' s p e c i f i c . r e s i d e n t i a l , site ... Levels of c o n c e r n mus"Cbe".'deyeloped', for .each. site an'd depending upon the various:;;:;^>r,>' ;ircumstances"; 'will _ likely' 1 'be different in differing sites."' • -^ :_•;''•::'-- ••;-,,; v oO./'^ �-.:•' . . •• . .•••.; . ' v ' . ' "..'• .REFERENCES' " ":;" - v'. ;;;; ';;;; Allen J R , ; Bcirsq^ti'DA.; Lambre : ckt. : ;LK,:. ; Uan .Miller . J P ' . v ; : , RGp^oductiyi^el^^^or 1 halog'enated : ;aro^tic^hyd^ ^979{320: 419-25 ;\/f./";C/ " :'\^:'.^V;v";^ ::•:•:-•'' ' ' I- '-. : • '" '. ' : •;»• ••'••• ••'-.::~'. '••"-'• •'••,-. ^'^Ul.iW^ Bauer'H^S^huizKH.^^pieg^ ! : hers teliung°uon^chlprphenol^o^ : i -. -'•-• i.^;i;-j ;^^^^^ ^j^!j^K^-j;^;i^;/ i36i-img$Ml^ A / « . • • Bucju •^•tf.^-tfW * Bleiberg ; ^ p ^ | i | | |^ norDhv'rlW/^V'ArcW^DermVtol;:' 1 :!^!;? porphyria l ! ! ; 'i^:'v P.i "; ;>-i : ; .y^i'^^.j*rl ! Carter CD, K i m b r o u o h ^ R D , Liddle J A C l i n e R F , Zack MM Jr, Barthel WF, " j '\ Koehler RE, Phillips PE. Tetrachlorodibfnzodioxin; An accidental poiconJng •• , *•• episode in horse arenas, . • • j, r >f Science 1975;188:738-^0. *r~M * < C o g g o n . D / . A c h e s o n ; . E D . ; ; D o ' p h e n o x y h e r b i c i d e s c a u s e cnncer. in > a n ? : : - Ujl£.ei ,->.-:. 1982;7:1057 r 1059, /;;';..:7. " • • . ' ^ - . - • V ' - ; - j'';. '"r , : , - ' : ' , . : , '.'.- ,' ' "; Copk R, Towns end.'J.'' <Jtt NG, a n d ' S i l u e r s t e i n G. M o r t a i l i t y , e x p e r i e n c e s ' o f , ;. e m p l o y e e s / e x p o s eiyip?;2 f '3/7^r>Vtrachlorodib 'igcU 1930;22:530--532 : ;: : Dioxin, chloracheV..and soft "tissue" sarcoma. .' Lancet 1931; 618: 3-14:^ �-25- Courtney KD, and Moore JA. Teratology studies with • •" '; '. .• . ••';'."-..: •'";;'-'./•'"' 2,4, 5-trichlorophenpxyacetic acid and 2,3,7, 8-tetrachlorodibenzo-p~dioxi.n;^;:: ~ Toxicol. 'XpP.l-v' 'Pharrnacol.' 1.97 1 ;'2Q ; 396-403 .- -' V.:''•-.''..' E r i k s s o n ' M , Berg N/Hardell 7 L> Moller: T, ;/ and ftxelson 6, ; ; ; : ; : • / r .-..;-;^,.: , :" 'V.'.i .-;'''"-:- 'V./-UV:: - ' ..:•=; ; ".'t • - - ' •••- - ' ' '• '' ' : '••; '"'•• "' V;" "^••'!l')-^-: Soft tissue ",.':.;•-'••^'•'• r '^t-''" -r-^ . -\' ^' and e x p o s u r e , to''- cherriical, subs.tances , a. c a s e - r e f e r re n t 'stud \/'-.-.'; i' B r ; '•;• J; V I n. ^'j.;.: ''?j : ' .•/-'••.'•'•" • ' • • ' . " • • ' • - ' • • • ' " ' - " ' " ' ' ' '"''- ' ! • ': ;' • ' . ; /v""':;';!>i-,"-/;"f; •-'•'.-:. ^"W,^;^^^*' " ^-^ ^.^^ "• ^' V;Vv;:ftV^.0; ??£tf.\-. 1 •' indings'-:v' ..'-'.'V '>'^--^.^--;--.i'-'>;l!1^v;'-"; .e'.wA-1u^ ; and.••indicators.-iof-:heauy:\Vi-• (•-.-• :• • i ' -r-- '.'• •; \-"^;-^?1--^'>/:^^::^:^^^-ri^'-::?f:f:t Hardell LK; and ..Sand.^troni.'ft'/:. Case-control 'study:* Sof ^--tissue 'sarcomas''and ^.;;-.exposure'i" -«------------•--••--'-;:---•-'- -••-• -»—---.:^.- -T ^>- 1979 Hardell L, Erik'son M',. Lenner P, Lundgren E. Malignant 1'ymphoma and exposure to chemical's, especiallyTorganic''solvents' chloroph.eno.ls and phenqxy. acids : -:; A case control study. B.rt 'J..._ Cancer - 1981; 43 , (2) : 169-76 . .'• Honchar P/ and Halper.in W.- / : . ; ./,':•' /; 2, 4, 5~trichlorophenol .'and- sof t Vissue'vsarccma';-^:: Lancet 1981;(1) ; 269 /;. :.:;;'V:."'. .'-. :\ '. -.'• •/; '' ' :: : .: ' ';^'. ' "" • ' '- ' •• ': t. '_ /';;.:v'"' �•26- :ftRC. Chlorinated dibenzodioxins. In: Monographs on the evaluation of the :arcinogenic risk of chemicals to man. Lyon, France ; WHO, 1978; 15 ;41—102'.. ..:',:;. Jensen NE,- Walker' ftEv. Chloracne;.. Three cases. .; Proc. 'R . Soc .••' ned;:'.;V.!-4-Hvyv^.;^.X} . , ' • .:'->::•. " •'•:.'- ^'^ .^'""- ;'. ;; -V*'-. ' •' • '-•' • ' ~~~~~ [•~^~~^.-"''~7': -:- .'.:T- . -''::v y ' lirasek I, Kalensky J, Kubec K, Pazderova J, Lukas E. -' _ ' Chlorakne, porphyria 4- ;utanea tar da und a n d e r e i n t o x i k a t i o n e n J u r c h h e r b i z ' d e v 1 9 7 6 - 2 7 328-33. ':'--'. ; - , : t i , - 4 !isJit^rvjc * • , • .- ' : . i '.imbrough RD. Halggenated b l p h e n y l s , t e r p h o n y l s , napthalenes dibenzodioxins I *' l * '* \ ' ' t . j n d related p r o d u c t s . Top; Enuiron.' Healti^ A m s t e r d a m , New Y o r k ; Elsevier N o r t i f i 'nuts'on JC;',.1s.nd.:Poland A ;.";•. Keratihization of"mouse teratoma cell line XB: >roduced by :2> 3 ,7, 8-tetrachlorodibenzo~p-dioxin : an iji :.uitjio model of:\ :oxlcit'y^;-'''C'eiV'^ , \ ^. .-:,);''/..-''',; •"'.; ':':". '\^-;^^i^]..--^^^:.-^i^:^^i :ociba RJ/ Keyes'DG, ; Beyer;.JE, Carreson RM, Wade EE, Dittenbar DA, Kalmins .RP, 'rauson LF, ..Park _DW/."Barnard SD/ ''Hummel RA, Hurhiston. CGV " Results' of a, tuo-; ;. .1 • - - • • • ' < ear chronic tdxicity and."6hcog"enicity study of 2, 3 , 7 , 8~tetrachlor;oa'ib'enzo— icity )-dioxin (JCDD) .in raiis. .rToxicol.. Appl. _P_harmacol... 1978; 46: 279-303'. �'•'.. : '' Kociba RJ, Sc'hujetz B f t . £TCDD). . ' - ' -27- ' ; .' ' '•• • T o x i c i t y of 2, 3 , 7 , 8 - t e t r a c h l o r o o ' l b e n z o - p ~ d i o x i n . D r u g . M e t a b o l i s m Reuieuis 1982; 1 3 ( 3 ) : 387-406. ...;;;/.,. , Lamb J C , : Moore 3A,' M a r k s ' T A . - E v a l u a t i o n , . o f 2 , 4 - d i c h l o r o p h e n o x y a c e t i c ' acid..-.-/ ( 2 , 4 - D ) , 2;'4', 5 - t r i c h l p r o p h e n o x y a c e t i c acid ( 2 , 4 , 5 - T ) , and ' "'. (••'•'•^:-'^'^^':f:^ 1, 3 , 7 , 8 - t e t r a c h l o r o d i b e n z o - p - d 4 o x i n (TCDp) t o x i c i t y in C 5 7 B L / 6 mice: .* ..^•- • '.. R e p r o d u c t i o n " a r i d f e r t i l i t y i n t r e a t e d 'male mice and. e v a l u a t i o n o f " c o n g e n i t a l . -----' J o i : n a l f o r m a t i'ons in their o f f s p r i n g . . .fiat 1.". Tox 1 co 1.._ Program', Res'earch T r i a n g l e institute;'-'. R ©y^eaVV h \.tri a ngl'e.'r. P a r k ' , ' NC..,' Re port Mo.' NTP-80-44/ 57pp.-;/iA;;vv^:v'^r: lay G. Chloracne frprh' the a c c i d e n t a l p r o d u c t i o n of tetrachlorocJiben2odioxin : : ' ••' - - ' - • ' < ' • ' •'•- ' - • • - o l - o a r ' h T rM^nrJ-i KdiT»rtri'4 rwi n •"'' a " s i r e n lay. G.: TetrachloroHib'enzpdioxin':l':a ' "o"iuK»Ivi o y ;' of s u b j e c t s ' ' tenk years ' af.ter.^^. • - '. v:^-••^^•^^5.-^v^'^vA-^/;:«::|-i ,;-,j-./ =•;•;: .";••.•>;;:.'V:---?;- ..•• • • • ^^.••^.•.•"•'^P^ : ; : x p o s u r e . ' ; -B'r/ J A Ind7' MedV" 1982;'39 :128-135. ": ' '--• • ' • • • . : . - - . '" "•'•':':'":^. IcConnell EEX; f-'i?-°.r.e^ JA«'.^Haseman^ JK-!, " H a r r i s . MW.- : The..comparafciue; toxic'it;y."".of ^ h l o r i n a t e d ciibenzo-p-'dioxins in mice and g u i n e a p i g s , < TJox,ic.pjU_' A££Lt.', • '' " h a r m a c o l . ; 1978b;'44:335-356. • ' : : '.'•'' '. ,.' . : '•v-.'';.- -, ' . " : , - . - " ' " ' • . - ' • ' " . ' - .""•'•• i c C o n n e l l EE, Moore JA, Dnlgard DW. " Toxicity of 2, 3 , 7 , 8-t9trachlorociiben;:o-p iioxin in . R h e s u s " r n p n k ' e y s " ' ( M a c a c a m u l a t t a ) ' following a s i n g l e oral 'dose.; . .,'.;...' "oxicol. fippl'.-" 'Pharrna'col/; l § 7 6 b ; 4 3 : 175-187. :' : ; ? : : ' • ' - . ••• ::-";"'.'".'..' : " ' / ' . . ; • �'• cNulty l\'P. •'"'. •' .:" •' : ' : - • ' •- •;.•" : i :' • ' • ' -28-. , • :• ;.,. : . • : : .' - . ./'. : : '';'"V -:. . '.-' Rhesus macaques: • Pertinence for'studies on the toxicity of ,.-'•'.. hlorinated hydrocarbon environmental pollutants. In: Chiarelli f>B;:v •••"''•••'? Berlin:".' ..."• ,. ; "- : .- l r '" arruccini P.S, ea'$V.\ Advanced . Uiews. in Primate Biology, ipringer-Verlag, 1982. '•. "( "' : u r r a y FJ, Srnith : FA, • N i t s c h k e K,D, . H u m i s t o n . CG, . K o c i b a R J , Schwetz Bft .'.'VTh'res ' * i "> *( e n e r a c i o n r e p r o d u c t i o n s t u d y o f r a t s g i v e n 2/3 , 7 , 8 - t e t r a c h l o r o •- ' * * i i b e n z o ~ p - d i o x i n (TCDD) i n * the d i e t . Tgxlcol,.. flpg,!^ .Pjia.npac.ol^^ 9 7 9 ; 50 241^252^ ,\^ * '-^! , V '1 r < *4 - « '* ational Toxicology P r o g r a m . C a r c i n o g e n e s i s b i o a s s a y of 2 , 3 , 7 , 8 > " i. ' > • "«• , e t r a c h l o r o d i b e n z o - p dioxin (CAS No, 1 1746-01-6) in Sun ss~K'obster mice i i ' ^ dermal study)...'.' Natl'-.'.Toxlcol; .Program/ T e c h . Rep,:. S'er'. : 1982a; Issue '201',"' 113 i . ,-- ; - . ' . • . • • . - . , , ational T o x i c o l o g y P r o g r a m , -,. Car.cinogenesis b i o a s s a y of \, 2 , 3 , 7t 8 :''•'' j - • ' . , . ' : e t r a c h l o r o d i b e r i z o - p f d i o x i n "(CAS fJo.- 1 1746-01-6) , i n , . O s b p r n e - M e n d e l rats' .a'nd 6C3F1 mice ( g a y a g a s t u d y ) . 982b;Issue/209, 195\pp. • N a t l .• Tox.ic.ol^^ Prog ram Tjecji^ R'feg.^ Sejv , • : -'.•.•'' eal' R f l , Olson Jr', G a s i e w i c s T A , G e i g e r L E . . /. • The toxicokinetics of. , 3 , 7 , S-tetrachlor'odib'snzo-p-dioxin in m a m m a l i a n s y s t e m s . ?_ 1982; 13: 355-386. ' , ' • ' . . ' ''. iliuer RM." ; . • ' r' ' ' : - •' / ' • •' Ojrjjg fjet ':- • ' / - ' . ' - . ' -••-'''•' Toxic' e f f e c t s o f 2 , 3 , 7 , 8 t e t r ^ c h l o r o d i b e n z o 1,4 clioxin " i n • ' ' . • • aboratory w o r k e r s . 8_r_/ J _._ IncL_ Ked_,. 1975; 32 : 49-53 , ••". '. :.. ^ �' •'•'-• /-. ;' • • ; ' '. -29- '. •• '••' ; ' )tt M, Holder B, Olson R. .ft mortality analysis of employees engaged in the' -imnufac'ture of 2,4,5-t'richlorophehoxyacetic acid. !- y Ot\Ji j• (, £, i• *r / "^O * Q f f 9 9 /L7 — ^ v '* ' 5 : ' • • ^7; r" ' , ' • . - ' ' " . ' ' • • '<• -r.1 • - -'-:-• • • • • •' • '' ' '••'• . • -• , . . " ' - , . ! ' ' :'.': '•• ;•'•";," ~ •' - -* • •- .- .. ' ...,'"• • •.'- '. . - ' . ' . • ' itot HC, 'Goldworthy T, Poland A . " : •' - ' J . J. Occup. Med^. • V .. • , . ' : '. '• • .• '• • , r . . . ', ' . '' ' '". . - . • . •'•. •;. • ' • • ' '• •• • . . . . . . ' . ' ' .- ,• .'-':, •":.-• • -. ..'' - '•• •".!'•-.'.-•'•-•.'.•''.' Promotion by 2 , 3 ,.7,3-tetrachlorodibenzo-p- J i o x i n of. h e p a t o c a r c i n o g e n e s i s -:f rom d i e t h y l n i t r o s a m i n e . . : . . C a n c e r Res ,_•• ' '• ;;,; : .' 1980; 40: 3616-20.":;^.. "v^: • '•:'^^^:^'{:^''\': '"•'.'.,•''.. ^, ' •'.- . ..: . ';.''"•'•.'•'• .'• .' . ''.'.'' 'r. •''.••••"";' 'olahcT.A',' and' ';<ende\A M ;v-V 2^V?\ 8-V2tr«chlorod mlecular :ontaminant '5 'robe' •" FecL ft, Gloyer'^E, .Kende.'ASv. '"St'e.repspec'ific^ h i g h , a f f i n i t y binding;-of. ,- :_| '• ? , 3 , 7 , 8-te'trachp'rodibenz'f3^pi-di^ hepatic, -"cy to'sbl'Jf.Jj. ^SBiolv:'chem;. <: S ,976a;25l74926r4946^^;vV:5P^^1^^ ' • ' * .. " - ' ' . • •.'.'•' .>'">!:" • • . " , * ' ' • ' . •s • > . "; • , ' " - ' '" • „ , ' ' ' • • - " ' • • • -.. d A,. Qr^enliee ,WF>' 'Kende i'ftS.^ .Studies on ^he mechanism .of action of th inated 'dib^nxd-p-Qioxins "• and related, 'compounds-. oland A y Palen D, Glouer E. -.airless mice. Annj. fU^ LC^J^ ' gcjlV Tumor promotion by TCDD in skin of HRS/j Nature 1982; 300: 271-3 . . oland ftp, Smith' D, Hatter G, Fossick P. ; A health su'ryey of workers in'a ,4-D and 2, 4, 5--T' plant . AjlpJu - Ejnulronj. • iiealth 197 1; 22; 316-27. .' . eggiani G. reas. .., .-. .'.^ Localized cohtaminatipn with TCDD-Seueso, Missouri and other Jo£ic_s dji ' Enui rjorV., jlealth i960 ; 4: 303-371 . , ... �=••.•.••'",:•• \eggiani G. ' . ' -3°- • • .--, .-..;.' Acute human exposure, to TCDD in Seveso, Italy. rnuiron.. Health 1960; 6:27-43. . ' " 3mith, AH, Fisher DO,.. Pearce N,; "league CA. .-.'. ,v\'.: 3\_ TpxlcoV^ and- ' . ;. . "". VV:•-.'. Do agricultural 'chemicals"", cause': ;oft-tissue', sarcoma? ' r Initial findings of-a case'control, study in f\JeuT' ': , "" '•'.'. Zealand. Community "Health Studies . 1982a;6 : 114—119 . ••-' '' . • , "''-:.••.. •' ; : ' • ; • • . • ; - Smith' AH ,. Fisher DO/^Giles'/HJ,. Pearc'o N." The New Zealand soft'tissue...sarcoma' case control study: interview'findings'.''concerning phenoxyacetic acid ';.'• ''I'•;• ;.'J'"-;''''-.'. trol" .•""'"^nb'1-^-;:^-^^-'".^^^-^"'1^''. ?•'!'"-' '-••':~:'-•^"•'•' • ' "' •' :'•••• --. "•"- •• '•....''••£'.•'.*: -. .;. v^ "^ sxposure. " ••,-•4P ."• Poster.'ses'sioniw.. 3rd International Symposium on Chlorinated Dio'xins '. and Related Iatedjc6'm^puhds):'..October•\12-14'':.': Salzburg', ftustria.;' lS82b - ;-V> ..••V;,^ r3 . •^'^^^^^^:^^J'^^ff^-:*J\ ;U(:1 ••'';-':;' •. / :--P'-:-::' '*-.':"'i:i ^&^y^:^\^ :''.' 3mith FA, Schwetz'.Bfl[;' Nitschke.. KDi ^'..Teratogenici'ty of ^••'•••;'•;--.: :-\;---«-.--^ K,h•'- V^'^i > 2,3,7, 8-tetrachlbr,odibenzo-p--dipxin ,in CF-1 mice . Toxicbl. fippl. Pharrnacolv OO ; 38: 517-23.•'.'- .;'. ' rt-7fi . 5 O . C 1 "7 ;: ', •••'.••• '•..'••• - • . • • • . • ' . i '• '.'•'. ' • •••'..-• : .' • : . . ' - - : . . - -...- : .,•:.•••;•.. . - . ; . • .. - - - . r : - : . ; v . . fhiess AM , •.Frentzel-Beyme R, : Link. Ri.. Mortality, s t u d y .of persons exposed. ,y.6 ..... . trichiorbphenpl-proc'ess iioxin in a ; trichiorbphenpl-proc'es accident t h a t o c c u r r e d in the BPiSF A G 1 on ' Jouember 17, • 1953 .- ; ''A.fiL 1S82 ; 3 : 179-189 . 'oth K, Sainfai-Kelle S, Sugar 3, D r u c e J. C a r c i n o g e n i c i t y testing of t h e . ; lerbicide 2 , 4 , 5 - t r i c h l o r o p h a n o x y e t h a n o l "containing dioxin and of pure r.iioxin n Swiss m i c e . . WaVurie., 1979;278: 538-549.; , , ' / ' . • ' . ; .• ' : '. . ; •• l "• - . ' • ' • �- • • • • • -si- • los JG, f-'oore JA,, Zinkl JG. • . Effect of 2, 3 , 7 , 8-tetrachlorodiben2o-p-dioxlry on '-.he immune' system of laboratory animals, 1973;5:U9-C2; ; •"'•=; 'i^-f^ • V^'vi.^V-"-'''V :'' ^nuiron^ H_ejj.t_h £jir_s_^e_ct .',.•' * " ' "•' '• ' •' . • '" •. ••• •'" • ' : e t r a c h l o r o d i b e n 2 o d i o x i n in a t r i c h l o r o p h e n o l 4 p r o c e s s a c c i d e n t . . J,,' f ied. 1980;'22;'l'l '-14':. "".;>• -.' ,: .-' '. HS/PHS/CDC S/33 ; '' .' . * :. *'•"• \" " •-'"V'''-;i " • ' ; .''-'•'.'::- r ' ••: ;' ' • :':'"':"'.vv'v\'''^;--'rv-^V'V%^'^'^:.^ Zack'J. Suskind R, The mortality experience of workers exposed to . • ' • •••"• ' , ; • • ' ' • '- •,.'•':• •-/ ;. • � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Alvin L. Young Collection on Agent Orange Description An account of the resource <p style="margin-top: -1em; line-height: 1.2em;">The Alvin L. Young Collection on Agent Orange comprises 120 linear feet and spans the late 1800s to 2005; however, the bulk of the coverage is from the 1960s to the 1980s and there are many undated items. The collection was donated to Special Collections of the National Agricultural Library in 1985 by Dr. Alvin L. Young (1942- ). Dr. Young developed the collection as he conducted extensive research on the military defoliant Agent Orange. The collection is in good condition and includes letters, memoranda, books, reports, press releases, journal and newspaper clippings, field logs and notebooks, newsletters, maps, booklets and pamphlets, photographs, memorabilia, and audiotapes of an interview with Dr. Young.</p> <p>For more about this collection, <a href="/exhibits/speccoll/exhibits/show/alvin-l--young-collection-on-a">view the Agent Orange Exhibit.</a></p> Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Box The box containing the original item. 066 Folder The folder containing the original item. 1761 Series The series number of the original item. Series III Subseries III Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Description An account of the resource <strong>Corporate Author: </strong>Center for Environmental Health, CDC Title A name given to the resource Typescript: Detailed Responses to Subcommittee Questions on Dioxin, for the Record, September 1983 Subject The topic of the resource soft tissue sarcoma animal studies ao_seriesIII https://www.nal.usda.gov/exhibits/speccoll/files/original/6e557b4dd98341b1aa4143c1bdf9bdca.pdf f94d8d48acca10e633409bc4d569daf9 PDF Text Text Rom D Number 02239 Author Tumasonis, Casimir Corporate Author Report/Article Title Typescript: Preliminary Report: Chick Embryos as a Probe of the Relative Toxicities of Soot Samples from a Polychlorinated Biphenyl-Containing Transformer, [nd] Journal/Book Title Year Month/Day Color Number of unaoes n 14 Descriptor) Notes Thursday, September 20,2001 Page 2289 of 2293 �PRELIMINARY REPORT CHICK EMBRYOS AS A PROBE OF THE RELATIVE TOXICITIES OF SOOT SAMPLES FROM A POLYCHLORINATED BIPHENYL-CONTAINING TRANSFORMER Casimir Tumasonis and Laurence Kaminsky Division of Laboratories and Research New York State Department of Health Albany, New York 12201 �Chick Embryos as a Probe of the Relative Toxicities of Soot Samples from a Polychlorinated Biphenyl-Containing Transformer. Tumasonis, C. and Kaminsky, L. The involvement of a polychlorinated biphenyl (PCB)-containing transformer in a fire resulted in widespread contamination of the State Office Building in Binghamton, New York with a soot-like material containing 1 ppm 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), 50 ppm 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), and relatively high concentrations of PCBs and other polychlorinated dibenzofurans and dibenzodioxins. The chick embryo system has been investigated as a rapid and inexpensive method for assessing the relative toxicities of large numbers of soot samples derived from different sites in the building, and as a means of assessing effectiveness of the clean up procedures. Samples were administered to the embryos in an aqueous 0.75% methyl cellulose vehicle via a hole drilled into the shell over the air sac. Soot exhibited the greatest embryo lethality when administered on day 4 of incubation. There was a non-linear dose related embryo lethal response with a marked saturation of embryo lethality between the 0.2 and 2.0 mg soot/egg doses. At 2.0 mg soot/egg administered in 0.1 ml aqueous vehicle approximately 50% of the embryos were dead by day 18 of incubation. No deaths were observed with the same quantities of active carbon or fireplace soot. Increasing volumes of vehicle increased the embryo lethal effects of the soot probably indicating that the non-linear dose response was partially due to a lack of availability of all the administered soot to the' inner air sac membrane. At doses of 2.0 mg Binghamton soot/egg some teratological effects were observed in �embryos surviving to day 18 of incubation. The effects included curled toes, anophthalmia, exencephaly and edema and occurred at low frequency and non-reproducibly. 2,3,7,8~TCDD when administered into the eggs at doses of up to 500 ng/egg in the aqueous vehicle and up to 800 ng/egg in corn oil killed 3 out 15 embryos at the highest dose and all embryos above 10 ng/egg in the two vehicles respectively. Further studies are underway to develop the chick embryo system for use in investigating the relative toxicities of different soot samples. �A fire which involved a transformer in the State Office Building in Binghamton, New York resulted in extensive contamination of the building with a soot-like material. The transformer contained a dielectric fluid (pyranol) which comprised 65% Arochlor 1254 (a polychlorinated biphenyl (PCB) mixture), 35% chlorinated benzenes and trace additives. Soot samples collected from two sites in the building were • contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF)(Smith et al., 1981a). Based on pyrolysis studies with PCBs it was predicted that the soot would also have relatively large contamination by other isomers and congeners of the polychlorinated dibenzo dioxins and dibenzofurans (Buser _et al., 1978). Predictions of the toxicity of the soot based on the known concentrations and toxicities of 2,3,7,8-TCDD and 2,3,7,8-TCDF are suspect for a number of reasons: Not all contaminating components of the soot can be determined, the toxicities of all polychlorinated dibenzodioxins and dibenzofurans is not known, the role of the soot matrix was not known (Silkworth et al., 1981) and the potential for synergistic or antagonistic effects of the pollutants on the toxicity of other pollutants is unknown. Thus there was a requirement for a toxicological assessment of the soot where it would be treated as a single compound. As part of the clean-up procedures in the building, assessments of the variations in toxicity of soot from different sites and at different times as the clean-up proceeds will require toxicologic analysis of numerous samples. A method was required which would provide a rapid analysis of large numbers of samples without enormous �resources of personnel and equipment. using chick embryos. These criteria could be met by In 1966 a group meeting under the auspices of the World Health Organization recommended that the chick embryo not be used for screening drugs for teratogenicity since it is "too sensitive to a wide range of agents and affords no parallel with the anatomical and physiological relationship existing between a pregnant mammal and her conceptus" (World Health Organization, 1967). Subsequently argu- ments have been raised in favor of the introduction of the use of chick embryos in teratology most notably by Gebhardt (1972) in the Netherlands and Wilson (1978) in the USA. A number of reports have appeared recently in which the chick embryo method has been used to investigate the teratogenicity of methylene chloride, trichlorethane, trichloroethylene, tetrachloroethylene and toluene (Elovaara et al. 1979), DDT (Swartz, 1980), cholinergic insecticides (Misawa et al., 1981) and Lambda-Carrageenan (Monis and Ravasio, 1981). The chick embryo has also recently been used to evaluate the cardiovascular teratogenicity of 2,3,7,8-TCDD (Cheung et jal., 1981). In this paper we report our preliminary investigations on the use of the chick embryo to investigate the relative toxicities of samples of soot collected in the state office building. The main criterion which will be used is embryo lethality rather than teratogenicity in view of the controversy associated with interpretation of teratological effects and the relative ease in assessing embryo lethality. �METHODS Fertile White-Leghorn chicken eggs (50-60 g) were obtained from a farm maintained by this Division. After collection the eggs were placed into a humidified (65-67% humidity), forced-draft incubator (Humidaire) and were incubated at 37.5° ±0.32°C to initiate embryo development. Contaminated soot was obtained with a vacuum cleaner fitted with clean collection bags from the stairwells of the third and fourth floors of the State Office Building in Binghamton, New York. It was filtered through a wire gauze to remove gross inert contamination. Extracts of the soot were prepared by Soxhlet extraction with benzene for 16 hr. Benzene was removed by heating the solution. 2,3,7,8-TCDD was obtained from Dow, Midland, MI as a solution in toluene. The soot was analyzed as previously reported (Smith _et al., 1981b). For administration of samples a small hole was drilled into the egg shell in the center of the airspace (determined by candling) and samples injected by a syringe (fitted with an 18g needle) onto the inner membrane. The hole was then immediately sealed with paraffin and the eggs incubated. At the end of the incubation period eggs were cracked open and the embryos were removed and evaluated for lethality, gross malformation, and subcutaneous edema. Surviving and non-auto- lized embryos were individually preserved in 10% neutral buffered formalin. Studies were performed to determine the optimal day of administration and day of termination, dose response-curve, effect of volume of vehicle, effect of polarity of vehicle and effect of the soot matrix on the toxicity of contaminants. The last study will be per- formed by comparing the embryo lethality of the soot itself with that �of the benzene extract of the soot. Effect of vehicle polarity was tested using 2,3,7,8-TCDD as the test compound. The vehicle chosen for most of the studies is 0.75% aqueous methyl cellulose. A similar system has recently been demonstrated to be a safe vehicle in teratological studies (Fritz and Decker, 1981). This vehicle has also been used in extensive studies of the toxicity of the soot in guinea pigs (Silkworth et al., 1981). �RESULTS AND DISCUSSION Thirty eggs were randomized into three groups of 10 each. On each of days 0, 3 or 4 of incubation one of the groups was inoculated with 2.0 mg spot/egg in 0.75% aqueous methyl cellulose (0.1 ml/egg). One half of each group was opened on day 14 and the remainder on day 18, and the embryos examined for viability. Administration on days 0, 3 and 4 resulted in a total of 17, 38 and 78% embryo deaths respectively. It was thus apparent that administration on day 4 was the most effective for the expression of soot toxicity in this system and all subsequent studies incorporate administration on day 4. In a series of studies designed to determine the dose response and reproducibility of embryo lethality, eggs were administered 0.02, 0.2 or 2.0 mg soot/egg in aqueous methyl cellulose into the air sac on day 4 of incubation. In each study 15 eggs/group were used. Two control articles, fireplace soot and active carbon, were also inoculated separately on day 4 into the air sac at doses of 2 mg/egg in the aqueous vehicle. lethality. In no case did the control articles result in embryo In two separate experiments 2 mg soot/egg led to 53 and 56% dead embryos indicative of the reproducibility of the system. However, studies repeated at periods over several months showed much greater variability. In one of these experiments only one of the soot-exposed embryo which survived the 18-day incubation exhibited anophthalmia, exencephaly, toe curl and a short upper beak while four other embryos exhibited edema. Toe curl was found for the majority of the chicks surviving up to the 18th day. In the duplicate experiment the only gross teratological effect observed was toe curl. In Fig. 1 the dose response curve for embryo lethality is shown. There was a marked saturation in embryo lethality between the 0.2 8 �mg/egg and 2.0 rag/egg close levels. To explain this we hypothesized that the aqueous soot-containing vehicle would form droplets on the inner membrane and that some' of the soot, distant from the droplet surface exposed to the membrane, would not be available for xenobiotic release to the embryo. To test this hypothesis we administered to groups of 15 eggs, doses of soot in differing volumes of vehicle. Doses of 1 mg/egg and 0.1 mg/egg were administered in 0.05, 0.10, 0.50 and 1.00 ml aqueous vehicle. No volume effect was noted at the low dose but at the high dose lethality increased with increasing volume until the highest volume where embryo lethality was diminished. Mor- talities were 13% at 0.05 ml, 20% at 0.1 ml, 40% at 0.50 ml and 27% at 1.00 ml. It is thus possible that low vehicle volume prevents com- plete exposure of the soot to the membrane. In a recent study (Cheung et al.f 1981) 2,3,7,8-TCDD was administered into the egg white of fertile chicken eggs in a vehicle of acetone/corn oil at doses of 0.003 to 25 ng/egg on day 0 of incubation. At no dose was there more than 45% lethality. The soot sample used in the current study has been reported to contain approximately 1 ppm of 2,3,7,8-TCDD and 50 ppm 2,3,7,8-TCDF (Smith et al., 1981b). At a dose of 2 mg soot/egg there was thus approximately 2 ng 2,3,7,8-TCDD/egg and 100 ng 2,3 ,7 ,8-TCDF/egg. In an effort to compare the soot embryo lethality with that of one of its similarly administered components, and to determine the effect of the aqueous vehicle relative to a more hydrophobic vehicle 2,3,7,8-TCDD was administered to the eggs in aqueous methyl cellulose or corn oil vehicles. Groups of 15 eggs received 0.1, 1.0, 5.0, 10.0, 100, 250 or 500 ng TCDD/egg in 0.1 ml aqueous methyl cellulose, or 10, �50, 100, 250 or 800 ng TCDD/egg in 0.10 ml corn oil, or 0.1 ml of the vehicles on day 4 of incubation, into the air sac. With the aqueous vehicle only the two highest doses were embryo lethal producing 1 and 3 deaths respectively. In contrast all doses above 10 ng/egg in corn oil killed all the embryos. The corn oil vehicle killed 4 embryos. While this study has not been completed it is apparent that the embryo lethality of the soot probably does not arise from the bound 2,3,7,8TCDD. The effect of corn oil itself in killing 27% of the embryos is consistent with a previous report that olive oil (25 yI/egg) injected into the air sac on day 3 of incubation killed 27% of the embryos by day 14 of incubation (Elovaara et al./ 1979). However, in another study (Kitos et al., 1981), corn oil when injected into the yolks of eggs at 50 yl/egg on day 6 of incubation produced no deaths of embryos by day 18. In conclusion we have demonstrated that the Binghamton soot produces embryo lethal effects when administered into the air sacs of fertile eggs under conditions where active carbon and fireplace soot have no effect. The lethal effects are dose dependent and also dependent on the volume of administration vehicle. One of the components of the soot, 2,3,7,8-TCDD, is markedly more toxic when administered in corn oil-than in an aqueous vehicle and it is possible that the apparent toxicity of the soot is similarly dependent on vehicle polarity. Further studies are underway to develop the chick embryo method for evaluation of relative toxicities of Binghamton soot samples. 10 �REFERENCES BUSER, H. R., BOSSHART, H.-P., and RAPPE, C. (1978). Formation of polychlorinated dibenzofurans from the pyrolysis of PCBs. Chemosphere 7, 109. CHEUNG, M. 0., GILBERT, E. P., and PETERSON, R. E. (1981). Cardiovas- cular teratogenicity of 2,3,7,8-tetrachlorodi-benzo-p-dioxin in the chick embryo. Toxicol. App1. P h armaco1. 61, 197-204. ELOVAARA, E., HEMMINKI, K., and VAINIO, H. (1979). Effects of methylene chloride, trichloroethane, tetrachloroethylene and toluene on the development of chick embryos. Toxicology 12, 111- 119. FRITZ, H., and BECKER, H. (1981). The suitability of carboxymethyl- cellulose as a vehicle in reproductive studies. Arzn.-Forsch. Drug Res. 31, 813-815. GEBHARDT, D. O. E. (1972). teratology. The use of the chick embryo in applied Adv. in Teratology 5_, 97-111. KITOS, P. A., WYTTENBACH, C. R., OLSON, K., and UYEKI, E. M. (1981). Precision delivery of small volumes of liquids to very young avian embryos. Toxicol. Appl. Pharmacol. 59, 49-53. MISAWA, M., DOULL, J., KITOS, P. A., and UYEKI, E. M. (1981). Teratogenic effects of cholinergic insecticides in chick embryos Toxicol. Appl. Pharmacol. 57, 20-29. MONIS, B., and RAVASIO, R. A. (1981). Teratogenic effect of lambdaCarrageenan on the chick embryo. Teratology 23, 273-278. SILKWORTH, J., MCMARTIN, D., DE CAPRIO, A., REJ, R., KUMAR, S., and KAMINSKY, L. (1982). Acute toxicity of soot from a polychlori- nated biphenyl-containing transformer fire, (in preparation). 11 �SMITH, R. M. , O'KEEFE, P. W., HILKER, D. L. , JELUS-TYROR, B. L. , and ALDOUS, K. (1981a). Chemical analysis of 2,3,7,8-tetrachlorodi- benzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran in a soot sample from the transformer explosion in Binghamton, New York. N.Y. State Dept. of Health Report. Feb. 20, 1981. SMITH, R. M., HILKER, D. L., O'KEEFE, P. W., KUMAR, S. , O'BRIEN, J., JELUS-TYROR, B. L., and ALDOUS, K. (1981b). Analysis of a Binghamton soot sample for tetrachlorodibenzofurans and tetrachlorodibenzo-p-dioxins. N.Y. State Dept. of Health Report/ October 1, 1981. SWARTZ, W. J. (1980). Dissimilarities in the toxic responses of early chick embryos to DDT administered in different vehicles. Bull. Environ. Contam. Toxicol. 25, 898-901. WILSON, J. G. (1978). Review of in vitro systems with potential for use in teratogenicity screening. J. Environ. Path. Toxicol. 2, 149-167. WORLD HEALTH ORGANIZATION, Techn. Rep. Ser. (1967) No. 364. 12 �Figure Legend Fig. 1. The embryo lethality of Binghamton soot as a function of dose. Soot was administered to fertile chicken eggs in 0.1 ml 0.75% aqueous methyl cellulose through a hole into the air sac on day 4 of incubation. The viability of the embryos was assessed on day 18 of incubation. 13 �PERCENT LETHALITY f>0 O CO a a ^-s b O � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Alvin L. Young Collection on Agent Orange Description An account of the resource <p style="margin-top: -1em; line-height: 1.2em;">The Alvin L. Young Collection on Agent Orange comprises 120 linear feet and spans the late 1800s to 2005; however, the bulk of the coverage is from the 1960s to the 1980s and there are many undated items. The collection was donated to Special Collections of the National Agricultural Library in 1985 by Dr. Alvin L. Young (1942- ). Dr. Young developed the collection as he conducted extensive research on the military defoliant Agent Orange. The collection is in good condition and includes letters, memoranda, books, reports, press releases, journal and newspaper clippings, field logs and notebooks, newsletters, maps, booklets and pamphlets, photographs, memorabilia, and audiotapes of an interview with Dr. Young.</p> <p>For more about this collection, <a href="/exhibits/speccoll/exhibits/show/alvin-l--young-collection-on-a">view the Agent Orange Exhibit.</a></p> Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Box The box containing the original item. 090 Folder The folder containing the original item. 2289 Series The series number of the original item. Series IV Subseries II Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Creator An entity primarily responsible for making the resource Tumasonis, Casimir Laurence Kaminsky Title A name given to the resource Typescript: Preliminary Report: Chick Embryos as a Probe of the Relative Toxicities of Soot Samples from a Polychlorinated Biphenyl-Containing Transformer, [nd] Subject The topic of the resource BSOB PCBs animal studies