Abstract 2083 Liquid Chromatography-Mass Spectrometry Analysis of the Effects of Atrazine Exposure in the Keystone Species Faxonius virilis

Atrazine is a pesticide of the triazine class and is one of the most used pesticides in North America. We are investigating the toxicological effects of atrazine exposure on the crayfish species, Faxonius virilis. The effects of atrazine exposure on crayfish are of interest because crayfish are a keystone species. Atrazine has been known to negatively impact many aspects of crayfish health; atrazine has been demonstrated to diminish the ability for crayfish to locate food and find a mate, it affects the expression and activity of detoxification enzymes, and it induces histological changes that demonstrate the toxicity of the pesticide. We aim to quantitate atrazine and its metabolites in crayfish hepatopancreas tissue to assess correlation between atrazine levels and the previously observed behavioral and physiological effects of atrazine. A method for extracting atrazine and its metabolites from the crayfish hepatopancreas tissue was developed and validated. The method involves liquid chromatograph-mass spectrometry (LC-MS)-based quantitation using isotopic internal standards for each analyte. Spike recovery tests resulted in recoveries over 90% for all analytes. To further validate the revised method, the limit of detection, the limit of quantitation, and intermediate precision were also determined. The validated method was used to investigate accumulation of atrazine and its metabolites in crayfish exposed to 100 ppb atrazine for four days compared to an unexposed control group. Additionally, an untargeted LC-MS metabolomics analysis was performed on the control and exposed groups to explore potential metabolic changes following atrazine exposure. Work reported in this presentation was supported by the National Institutes of Health Common Fund and Office of Scientific Workforce Diversity under three linked awards RL5GM118981, TL4GM118983, 1UL1GM118982 administered by the National Institute of General Medical Sciences. Work was also supported by the UDMPU Internal Research Fund.