Feasibility of using comparative risk assessment for chemical burden of disease assessments

Abstract According to the WHO, about 22% of global disability-adjusted life years (DALYs) can be attributed to environmental risks. However, comprehensive DALY estimates for chemicals are still lacking. In this study, we present a first assessment of the disease burden due to chemicals performed within the European Topic Centre on Human Health and the Environment. We selected the chemicals (groups) lead, cadmium, PFAS, pyrethroids, phthalates, and bisphenol A and estimated the disease burden for 15 risk-outcome pairs. The feasibility of using the comparative risk assessment (CRA) approach was tested, and where possible, DALYs were calculated. Data gathered within HBM4EU were used for exposure assessment. For the case studies, we selected countries with available data on both exposure and health effects. It was feasible to use the CRA, however, a major limitation was the availability of exposure data from human biomonitoring studies in EU countries. E.g. for lead, the disease burden was only calculated for a maximum of 3 countries per health outcome. Here, for mild intellectual disability, the highest number of DALYs was estimated for Germany, with 950 DALYs/1 m. persons aged 3-11 years. For PFAS, a larger set of countries was considered with the highest burden estimated for IQ-loss with 437 YLDs/1 m. babies born in France. Further, the burden due to phthalates was estimated for selected metabolites in up to 19 countries. The highest burden was estimated for the metabolite DEHP and diabetes mellitus, with about 1,324 YLDs/1 m. women in Poland (≥ 25 years). The experience from the analyses supported the feasibility of using CRA for quantifying the burden of disease due to chemicals based on HBM data. The results show that a significant burden can be attributed to the 6 chemicals in the selected European countries. However, exposure data are available only for a small group of European countries, which hampered a European-wide assessment.