Human Dietary Exposure to a Large Spectrum of Chemicals from a Multi-Centre Sub-Saharan Africa Total Diet Study: Safety Assessment of Potential Impacts on Public Health and Implications for Policy Makers

Background: Human dietary exposure to chemicals may result in a wide spectrum of adverse health effects. Some substances may cause non-communicable diseases including cancer and coronary heart diseases, and also be nephrotoxic. Food is the main human exposure route of many chemicals. A cost effective methodological approach called Total Diet Study was for the first time used to assess human dietary exposure to a wide spectrum of food chemicals in Benin, Cameroon, Mali, and Nigeria. Methods: This Total Diet Study covered, with 4020 representative samples of foods prepared as consumed, more than 90% of the diet of 7291 households from eight study centres. By combining representative dietary surveys of countries with findings regarding concentrations of 872 chemicals in foods, human dietary exposure was characterized. Findings: Exposure to lead may result in increases in adult blood pressure up to 2·0 mm Hg while children may lose 8·8-13·3 IQ points (95 th percentile in Kano). Morbidity factors due to co-exposure to aflatoxin B1 and hepatitis B virus, as well as sterigmatocystin and fumonisins, suggest several thousands of additional liver cancer cases per year, as well as a significant contribution to the burden of child chronic malnutrition. Exposures to 13 polycyclic aromatic hydrocarbons from consumption of smoked fish and edible oils exceeded levels associated with possible carcinogenicity and genotoxicity health concern in all study centres. Exposures to aluminium, ochratoxin A and citrinin indicate a public health concern about nephropathies. Interpretation: Risks characterized by the study underscore specific priorities in terms of food safety management in Sub-Saharan Africa. The need for similar investigation specifically targeting children is critical. Funding Statement: The study was funded under grant STDF/PG/303, Standard and Trade Development Facility Declaration of Interests: The authors declare no competing interest. Ethics Approval Statement: Not required.