Exposure to known and emerging groundwater contaminants significantly alters poultry microbiome and metabolome

The exposome represents a summation of exposures which influence an individual's health over their lifetime. Understanding the exposome will aid in determining the environmental factors that contribute to disease states. Due to the complexity of the exposome and the resulting high dimensionality of the data, it is relatively difficult to predict adverse health outcome resulting from a summation of exposures. Therefore, accurate and relevant exposome criteria for biological assays is the first step toward addressing the current knowledge gaps for exposome research. The study aims to assess the presence of and health effects from exposure to contaminants in Wisconsin groundwater. We focused on three co-occurring chemicals that were detected at concentrations exceeding groundwater standards (i.e., nitrate, atrazine and imidacloprid) and the emerging contaminant, microplastics (i.e., polyethylene fiber). The agricultural chemical mixture of nitrate, atrazine and imidacloprid represent a known and ecologically relevant contaminant because each chemical individually has health risk levels established. Microplastics (MPs) are plastic fragments less than 5 mm in diameter that have been implicated in intestinal toxicity, altered metabolites, and other adverse health outcomes following exposure. In recent years, MPs have increasingly been found in locations where there could be an interaction with pesticides. However, there is limited knowledge regarding the impacts of MPs on the health of terrestrial species such a poultry. In this study, broilers chickens were exposed to either the ternary chemical mixture, at a low and high concentration, or polyethylene fiber MPs for 49 days. Overall, we observed significant perturbations to the cecal microbiome and metabolome of broiler in all exposure groups.