The effect of toxic metals in drinking water on the human microbiome

Abstract

S15: Interaction between environmental chemicals and toxicants and the human microbiome, Room 217, Floor 2, August 28, 2019, 10:30 AM - 12:00 PM In utero and early life exposure to inorganic arsenic occurs primarily through drinking water and food and is associated with altered immune response, including infant’s risk of infections. In animal studies, and in our own cohort study of infants, greater exposure to arsenic during infancy associated with differences in the gut microbiome composition and the relative abundance of individual microbial taxa. However, the functional significance of these changes is not well understood but is critical for determining the direct impacts of microbial gene products on host immunity and metabolism. Therefore, in addition to taxonomic profiling and metagenomic analyses, we analyzed infant stool samples using 1H NMR on a Bruker Avance III 700 MHz NMR Spectrometer and concentration-fit 36 known microbial metabolites using Chenomix. We examined the relation between these metabolites and both in utero and 6-week log 2 urinary arsenic concentrations in linear regression models, adjusted for infant sex, age, type of delivery (vaginal vs. C-section), feeding mode (breast milk vs. any formula) and specific gravity. In our preliminary analyses, higher 6-week urinary arsenic concentrations were associated with increases in butyrate, propionate, asparagine, malonate, leucine, cholate, and tryptophan (p<0.05). Metabolomic analyses of infant stool samples provide further support to our initial findings that suggests that the infant gut microbiome is sensitive to arsenic exposure and may influence early immune system development.