In the framework of the first multi-centre Sub-Saharan Africa Total Diet Study (SSA-TDS), 2328 commonly consumed foods were purchased, prepared as consumed and pooled into 194 composite samples of cereals, tubers, legumes, vegetables, nuts and seeds, dairy, oils, beverages and miscellaneous. Those core foods were tested for mycotoxins and other fungal, bacterial and plant secondary metabolites by liquid chromatography, coupled with tandem mass spectrometry. The highest aflatoxin concentrations were quantified in peanuts, peanut oil and maize. The mean concentration of the sum of aflatoxins AFB1, AFB2, AFG1 and AFG2 (AF_tot) in peanut samples (56.4 µg/kg) exceeded EU (4 µg/kg) and Codex (15 µg/kg) standards. The AF_tot concentration (max: 246.0 µg/kg) was associated with seasonal and geographic patterns and comprised, on average, 80% AFB1, the most potent aflatoxin. Although ochratoxin A concentrations rarely exceeded existing Codex standards, it was detected in unregulated foods. One palm oil composite sample contained 98 different metabolites, including 35.4 µg/kg of ochratoxin A. In total, 164 different metabolites were detected, with unspecific metabolites like asperglaucide, cyclo(L-pro-L-val), cyclo (L-pro-L-tyr), flavoglaucin, emodin and tryptophol occurring in more than 50% of composite samples. Aflatoxin B1 (AFB1), fumonisin B1 (FB1), sterigmatocystin (STC), ochratoxin A (OTA), citrinin (CIT) and many other secondary fungal metabolites are frequent co-contaminants in staple foods, such as maize and sorghum. Populations from North Cameroon and from Benin may, therefore, suffer chronic and simultaneous exposure to AFB1, FB1, STC, OTA and CIT, which are prevalent in their diet.

For the first time, a multi-centre Total Diet Study was carried out in Benin, Cameroon, Mali and Nigeria. We collected and prepared as consumed 528 typical fatty foods from those areas and pooled these subsamples into 44 composites samples. These core foods were tested for a wide spectrum of POPs, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs), brominated flame-retardants (BFRs), organochlorine compounds (OCs), perfluoro alkyl substances (PFAS) and chlorinated flame retardants (CFRs). The POPs contamination levels were similar or lower than those reported in total diet studies previously conducted worldwide. In most cases, core foods belonging to fish food group presented higher POPs concentrations than the other food groups. Interestingly, we observed a difference in both contamination profile and concentration for smoked fish compared to non-smoked fish. Such finding suggests that the smoking process itself might account for a large proportion of the contamination. Further investigation would require the assessment of combustion materials used to smoke fish as a potential vehicle, which may contribute to the dietary exposure of the studied populations to POPs.

Foodborne diseases are important causes of illness and death. The first estimates of their burden were published by WHO in 2015. We updated WHO estimates of the global, regional, subregional, and national foodborne disease burden caused by 42 infectious and chemical hazards in 2021, including time trends for 2000-21. We provide a high-level summary of foodborne disease burden, expressed as incidence, deaths, and disability-adjusted life-years (DALYs). Data for burden estimation were provided from a WHO-commissioned series of systematic reviews on the incidence, aetiology, sequelae, and case fatality or mortality of the hazards. Data were analysed using hierarchical meta-regression modelling with geographical clustering and a global linear time trend, disease-specific computational models, and uncertainty propagation through Monte Carlo simulations to calculate 95% uncertainty intervals. Attribution to foodborne transmission was principally based on a structured expert judgement process. Economic impact was measured as lost productivity. For 2021, foodborne transmission of the 42 hazards caused 866 million (95% uncertainty interval 680-1090) illnesses, 1·52 million (0·783-2·51) deaths, and 57·1 million (39·4-81·1) DALYs. Inorganic arsenic, lead, and non-typhoidal Salmonella enterica (diarrhoeal and invasive disease) resulted in the most DALYs. The greatest burden of foodborne disease was in the African and South-East Asia regions. The incidence in children younger than 5 years was 2·7 times higher than in people aged 5 years or older, resulting in 4·3 times the rate of DALYs. The total burden from all hazards decreased over time. In 2021, these 42 hazards resulted in productivity losses of US$310 billion in nominal terms, and US$647 billion after adjusting for purchasing power parity. Foodborne diseases causes a burden similar to that from tuberculosis, HIV and AIDS, or malaria. The high burden of both communicable and non-communicable foodborne diseases requires countries to prioritise developing strategies to improve the safety of the food supply. WHO.

Human dietary exposure to chemicals can result in a wide range of adverse health effects. Some substances might cause non-communicable diseases, including cancer and coronary heart diseases, and could be nephrotoxic. Food is the main human exposure route for many chemicals. We aimed to assess human dietary exposure to a wide range of food chemicals. We did a total diet study in Benin, Cameroon, Mali, and Nigeria. We assessed 4020 representative samples of foods, prepared as consumed, which covered more than 90% of the diet of 7291 households from eight study centres. By combining representative dietary surveys of countries with findings for concentrations of 872 chemicals in foods, we characterised human dietary exposure. Exposure to lead could result in increases in adult blood pressure up to 2·0 mm Hg, whereas children might lose 8·8-13·3 IQ points (95th percentile in Kano, Nigeria). Morbidity factors caused by coexposure to aflatoxin B1 and hepatitis B virus, and sterigmatocystin and fumonisins, suggest several thousands of additional liver cancer cases per year, and a substantial contribution to the burden of chronic malnutrition in childhood. Exposure to 13 polycyclic aromatic hydrocarbons from consumption of smoked fish and edible oils exceeded levels associated with possible carcinogenicity and genotoxicity health concerns in all study centres. Exposure to aluminium, ochratoxin A, and citrinin indicated a public health concern about nephropathies. From 470 pesticides tested across the four countries, only high concentrations of chlorpyrifos in smoked fish (unauthorised practice identified in Mali) could pose a human health risk. Risks characterised by this total diet study underscore specific priorities in terms of food safety management in sub-Saharan Africa. Similar investigations specifically targeting children are crucially needed. Standards and Trade Development Facility.