Neonicotinoids are the most widely used class of agricultural insecticides in the world. Between 2001-2014 usage increased by 3,929 times in Iowa alone.  Despite concerns that neonicotinoids may have a toxic effect on mammalian neurodevelopment, few studies have been conducted to characterize human exposure to neonicotinoids or the insecticides’ potential health risks.  Researchers from the College of Public Health, Civil and Environmental Engineering, the State Hygienic Laboratory, and the University of Iowa’s Maternal-Fetal Tissue Bank (MFTB) will randomly test urine samples from 350 women enrolled in the MFTB for the presence of seven parent neonicotinoids and at least 2 common metabolites - desnitro-imidacloprid and imidacloprid urea.  A cross-sectional study will then be conducted to test the association of exposure to neonicotinoids with the occupation of the maternal donor.  The proposed study will be the first to investigate exposure risks amongst farmers.