WHO estimates of the global, regional, and national disease burden of nine foodborne chemicals, 2000–21: an updated data synthesis

Background: We updated WHO estimates of the global, regional, and national foodborne disease burden caused by chemical hazards. We estimated incidence, mortality, and disability-adjusted life-years (DALYs) of aflatoxins B1 and M1, inorganic arsenic, lead, methylmercury, cadmium, dioxin, peanut allergy, and cassava cyanide for 2000–21. Methods: We used data from systematic reviews, established dose-response relationships, the Global Burden of Disease Study 2021, and, where applicable, a structured expert judgment study. We used disease-specific models and a hierarchical meta-regression model with geographical clustering and global linear time trend with uncertainty propagation. Findings: In 2021, the nine foodborne chemicals caused 6·26 million (95% uncertainty interval [UI] 3·36–10·30) cases, 1·12 million (0·40–2·10) deaths, and 29·8 million (12·9–53·1) DALYs globally. Inorganic arsenic and lead caused the highest burden. Cardiovascular diseases due to inorganic arsenic and lead caused 88·9% of foodborne chemical deaths and 76·5% of foodborne chemical DALYs. The greatest DALY rate was estimated for the South-East Asia region, with 789 DALYs (272–1660) per 100 000 people mostly due to inorganic arsenic and lead (94·2%). The region of the Americas carried the highest foodborne chemical DALY rate in children younger than 5 years, with 749 DALYs (435–1260) per 100 000 children, mainly due to the effect of methylmercury on intellectual disability (91·0%). DALY rates from dioxin showed the steepest decrease from 2000 to 2021. Interpretation: Dietary exposure to chemicals causes a substantial global disease burden. An integrated response with ongoing non-communicable disease prevention efforts is key. Granular assessment including subnational exposure contexts is essential to ensure equity. Funding: WHO.