ExpoKids: An R-Based Tool for Characterizing Aggregate Chemical Exposure During Childhood
Aggregate exposure, the combined exposures from all pathways to a single chemical, is a critical children’s health issue. To capture potential differences in aggregate exposure at various childhood lifestages compared to those of adults, we developed ExpoKids (an R-based tool) using exposure estimates across lifestages generated by the publicly available US EPA’s Exposure Factors Interactive Resource for Scenarios Tool (ExpoFIRST). ExpoKids illustrates aggregate oral exposures as average daily doses (ADD) and lifetime average daily doses (LADD) in 5 graphs organized across 7 postnatal and adult lifestages and 10 media. This visualization tool conveys ExpoFIRST findings, from available exposure data, in order to highlight the relative contributions of media and lifestages. To evaluate the effectiveness of ExpoKids, three chemical case examples [di(2-ethylhexyl) phthalate (DEHP), manganese, and endosulfan] were explored. Research questions regarding media and lifestage contributions to aggregate exposure across lifestages were asked and data available in the published literature and databases for each case example were used. These illustrative case examples demonstrate ExpoKids’ versatile application to explore a diverse set of children’s health risk assessment and management questions by visually depicting specific media and lifestage contributions to aggregate exposure.