Neonicotinoid pesticides are the most widely-used insecticides in the world. As such, they are commonly found in rivers and streams of the Midwest and have recently been detected in drinking water. Although neonicotinoids are potent toxins to insects, it is possible that they may react in the environment through natural processes or during water treatment to produce byproducts that may endanger human health. This work will examine the fate of neonicotinoids in the environment, focusing on processes that may amplify the risk they pose to human health. This work will help ensure that watershed-level efforts to improve water quality are more effective in limiting the release and persistence of neonicotinoids to protect the Nation's drinking water sources. Additionally, this project will train and educate students on scientific measurements, engage young students and the public (including underrepresented groups) on water quality, and help inform future risk assessments. <br/><br/>The central objective of this study is to establish the public health risks posed by the widespread use of neonicotinoid insecticides through the identification of major fate pathways and persistent bioactive transformation products along the continuum from source water to drinking water. The central hypothesis is that alteration of the critical neonicotinoid pharmacophore generates novel transformation products with differing environmental fates, increased human hazards, and exposure potentials relative to the parent insecticides. Specific objectives of this project are to: 1) identify and quantify the generation of novel neonicotinoid disinfection byproducts with altered pesticide pharmacophores; 2) quantify differential sorption characteristics of neonicotinoids with altered pharmacophores; and 3) measure the microbial transformation of the neonicotinoid pharmacophore during water treatment. Research outcomes will include improved risk assessments, water treatment technologies, and best management practices for neonicotinoids. Understanding these transformation mechanisms will also help inform the future design of more environmentally responsible target-specific pesticides. These research efforts are complemented by education and engagement efforts that will: 1) broaden participation in STEM through participation of three high school students from traditionally underrepresented groups via the Iowa Secondary Student Training Program; 2) engage K-12 students through participation in the Iowa STEM festival with an interactive display on non-point source pollutants; 3) promote the interdisciplinary research, training, and education of graduate students by leveraging an NSF NRT INFEWS grant program at the University of Iowa; and 4) in partnership with the University of Iowa Public Policy Center, broadly disseminate research outcomes to technical and non-technical audiences, including policy makers.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.