Susceptibility of Human Populations to Environmental Exposure to Organic Contaminants

Environmental exposure to organic contaminants is a complex function of environmental conditions, food chain characteristics, and chemical properties In this study the susceptibility of various human populations to environmental exposure to neutral organic contaminants was compared An environmental fate model and a linked bioaccumulation model were parametrized to describe ecosystems in different climatic regions (temperate, arctic, tropical, and steppe) The human body burden resulting from constant emissions of hypothetical chemicals was estimated for each region An exposure susceptibility index was defined as the body burden in the region of interest normalized to the burden of the same chemical in a reference human from the temperate region eating an average diet For most persistent chemicals emitted to air, the Arctic had the highest susceptibility index (max 520) Susceptibility to exposure was largely determined by the food web properties The properties of the physical environment only had a marked effect when air or water, not food, was the dominant source of human exposure Shifting the mode of emission markedly changed the relative susceptibility of the ecosystems in some cases The exposure arising from chemical use clearly vanes between ecosystems, which makes an understanding of ecosystem susceptibility to exposure important for chemicals management.