Variables Affecting the Environmental Fate, Safety, and Efficacy of Chlorate Salts Proposed for Use in Beef Cattle Production as a Food Safety Tool

Findings: Chlorate salts are being developed as a feed additive to reduce the numbers of harmful bacteria in live cattle. A series of studies was conducted to determine whether chlorate would also reduce the populations of harmful bacteria in cattle wastes (a mixture of urine and feces) and to determine the fate of chlorate after excretion from cattle. Chlorate salts present in manure had no significant effects on two harmful bacterial species, E. coli O157:H7 and Salmonella Typhimurium, probably because chlorate was very rapidly degraded and because relatively low concentrations of chlorate salts were used relative to concentrations that have been shown to kill harmful bacteria in live animals. Chlorate degradation was slowest with low temperatures (5 °C) and the fastest at the highest temperatures (30 °C) tested; nevertheless, even at cool temperatures chlorate degradation occurred in significant quantities. From an environmental standpoint, chlorate use in feedlot cattle would likely have minimal impacts because any chlorate that escaped degradation on the feedlot floor would be degraded in lagoon systems. Collectively our results suggest that the use of chlorate as a food safety tool would be environmentally friendly.