Acute Exposure to Groundwater Contaminants Mixture of Nitrate, Atrazine, and Imidacloprid Impacts Growth Kinetics of Poultry Cecal Microbiomes and Significantly Decreases Caco‐2 Cell Viability

Atmospheric deposition and agricultural runoff or erosion events have substantially contributed to groundwater pollution throughout the USA. This can become troublesome in states like Wisconsin, where 68% of the population relies on groundwater for their drinking water source. As such, exposome research must account for the complexity and frequency of environmental exposures. This study aimed to elucidate chemical‐biological interactions and adverse outcome pathways associated with an environmentally relevant mixture of agricultural chemicals detected in Wisconsin groundwater via in vitro and in silico methodologies. Using in vitro models, we determined that a ternary mixture of environmentally relevant concentrations of nitrate, atrazine, and imidacloprid resulted in an overt decline in growth rate in the poultry cecal microbiome compared to each chemical singularly. Further, there was a decrease in Caco‐2 cell viability in various two‐chemical combinations. In silico methods analyzed contaminants detected in Wisconsin groundwater wells from across the state and prioritized two groundwater wells as potential for health concerns. Prioritized chemicals in these groundwater wells were linked to nine gene targets and several adverse outcome pathways. In all, the results demonstrated that there is chemical‐biological interaction between these model organismsand agricultural chemical mixtures at real‐world exposure concentrations.