Human exposure to polychlorinated biphenyls embodied in global fish trade

Abstract

International food trade poses food safety risks through the collateral transport of contaminants that are harmful to human health. Persistent organic pollutants, such as the polychlorinated biphenyl (PCB) congener PCB-153, are consumed via fish intake traded globally, but the estimated daily intake and risk to human health are poorly understood. Using a food trade pathway model, a global-scale atmospheric persistent organic pollutant transport model and UN Global Comtrade data, high PCB exposure was identified in Western Europe. Marine fish exported from Europe to Sub-Saharan African countries account for 84% of PCB-153 consumer exposure. In contrast, European fish consumers face reduced exposure to PCB-153 by consuming marine fish imported from countries where PCB-153 concentrations are low. People consuming aquaculture-farmed salmon fed with marine ingredients from PCB-153-contaminated seawaters face a higher PCB exposure. Our findings demonstrate that global fish trade can exacerbate PCB-153 exposure in regions where environmental PCB-153 levels are low. This approach demonstrates how the exposure to harmful food contaminants distributed through global food trade can be predicted and quantified. Food safety is jeopardized by the global trade in contaminated foods. Huang et al. demonstrate how consumer exposure to the toxic chemical polychlorinated biphenyl-153 (PCB-153) can be modelled and identify regions with high consumer PCB-153 exposure resulting from imported fish consumption.