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Lead is a ubiquitous dietary contaminant that occurs in food because of natural and anthropogenic sources and pathways of exposure. Lead adversely affects a number of tissues and organ systems and the severity of effect on each is dependent on the level and duration of exposure. The most sensitive and notable effects are those that occur on the nervous system. This is particularly the case in the exposure to the fetus, infant and child. Infants and children generally have higher lead exposures on a body weight basis. While lead exposure can come from many sources, a major source of exposure for at least some individuals comes from food. Estimates for the impact of dietary lead on IQ were developed from published total diet studies. While most of these were designed to characterize intake of chemical contaminants on a national basis, some sampled market baskets from a single city. To develop global estimates, default ranges were created for countries with no data which encompassed the values encountered elsewhere. Blood lead levels and IQ decrements were estimated using functions previously developed by the WHO Joint Expert Committee for Food Additives. Since both the exposure and dose response components were variable and uncertain, a two dimensional Monte-Carlo simulation was used to develop the estimates for the impact of dietary lead on IQ. In addition to estimating blood lead and IQ decrements attributable to dietary lead from those countries with published market basket data, simulations were also run for WHO regions that sampled in the variability dimension based on the population size of the individual countries in each region. Dietary exposure to lead occurs throughout the world. The global average IQ decrement attributable to dietary lead was 1.1. The total number of Disability-Adjusted Life Years (DALYs) arising from those IQ decrements were estimated to be 5.2 million DALYs, with an uncertainty range of 0–31 million DALYs. Significant uncertainties regarding exposure and dose-response relationships, however, warrant continued investigation. • We assessed the global burden of dietary lead exposure. • We considered mild, moderate, severe and profound intellectual disabilities. • The global average IQ decrement attributable to dietary lead was 1.1. • In 2015, the global burden was 5.2 million Disability-Adjusted Life Years. [ABSTRACT FROM AUTHOR]

Abstract Arsenic is a ubiquitous, naturally occurring metalloid that poses a significant risk for human cancer and non-cancer diseases. It is now evident that arsenic contamination in food, especially rice and grains, presents a significant exposure to hundreds of millions of individuals worldwide. However, the disease risk from chronic exposure to the low amounts of arsenic found in food remains to be established. Thus, this research estimates the global burdens of disease expressed as Disability-Adjusted Life Years (DALYs) for lung, skin and bladder cancers, as well as coronary heart disease (CHD) attributable to inorganic arsenic in food. To determine foodborne inorganic arsenic exposures worldwide, we used the World Health Organization (WHO) estimates of food consumption in 17 country clusters, in conjunction with the reported measurements of total and inorganic arsenic in different foods. We estimated cancer potency factors for arsenic related bladder and lung cancers, and from US Environmental Protection Agency risk estimates for skin cancer to calculate the cancer incidence in males and females within each of the WHO member states. Summary relative risk estimates and population attributable fractions were developed to estimate the YLD, YLL, and DALYs for arsenic-induced CHD. The findings indicate that, globally, each year the combined DALYs for all cancers attributable to inorganic arsenic in food are approximately 1.4 million with variation in global distribution based on population and food consumption patterns. The global burden of CHD attributable to foodborne inorganic arsenic also varied with WHO region and may contribute as much as 49 million DALYs. However, in contrast to cancer burden, there is a threshold effect for arsenic-associated CHD with no increased risk of heart disease at the expected lower bound of arsenic consumption in food. These estimates indicate that foodborne arsenic exposure causes a significant yet avoidable global burden of human disease. Highlights • We assessed the global disease burden from dietary arsenic exposure. • We considered coronary heart disease (CHD) and skin, bladder and lung cancer. • In 2015, dietary arsenic exposure was associated with 240,000 cancer cases. • Dietary arsenic was associated with up to 4.3 million CHD cases in 2015. • The global disease burden was 50.5 million Disability-Adjusted Life Years. [ABSTRACT FROM AUTHOR]

Abstract We describe analyses to estimate the global burden of disease associated with methylmercury (MeHg). An intelligence quotient < 70, indicating intellectual disability (ID), was selected as the critical disease, maternal hair Hg concentration during pregnancy selected as the critical exposure biomarker, and a dose-effect relationship of an 0.18 point IQ reduction per µg/g increase in maternal hair Hg was assumed, based on a meta-analysis. A systematic review was conducted to obtain country-specific data on the distribution of maternal hair Hg concentrations. The country-specific incidence of MeHg-associated ID was calculated, and a random effects model was used to impute the incidence for countries for which no exposure data could be found. The global burden of MeHg-associated ID was quantified in terms of Disability-Adjusted Life Years (DALYs) using the World Health Organization (WHO) Global Health Estimates methodology, and presented by 14 subregions. In 2015, the global total for MeHg-associated cases of ID was 226,655; 210,074 of these cases (93%) were mild cases of ID. The highest rate of ID (6 cases per 100,000 population) was found in the Americas D subregion. The global DALY estimate was 1,963,869. The Western Pacific B subregion contributed the most to this total (696,417), although the Americas D subregion had the greatest rate (54 DALYs per 100,000 population). The burden of disease associated with MeHg is therefore highly subregion-dependent even in areas that are geographically related. The priority given to reducing this burden can therefore be expected to vary considerably by subregion depending on other health needs. Highlights • Diet is the primary pathway for exposure to methylmercury (MeHg). • Prenatal exposure to MeHg causes impaired cognitive development. • Globally, MeHg causes nearly 250,000 cases of intellectual disability per year. • MeHg associated intellectual disability represents nearly 2 million DALYs globally. • The Western Pacific B subregion accounts for more than one third of the DALY. [ABSTRACT FROM AUTHOR]

Abstract Chronic exposures to cadmium (Cd) are associated with reduced glomerular filtration rate (GFR), increasing the risk of chronic kidney disease (CKD). In support of the World Health Organization (WHO)'s initiative to estimate the global burden of foodborne diseases, a risk assessment was performed to estimate the Disability-Adjusted Life Years (DALYs) due to late-stage CKD associated with dietary exposures to cadmium. Using the distribution of population GFRs, the prevalence of CKD was calculated as the proportion of humans whose GFR fall in the ranges corresponding to Stage 4 or Stage 5 CKD. The increase in the CKD prevalence due to cadmium exposure was simulated based on a previously reported pharmacokinetic model describing the relationship between dietary cadmium intake and urinary cadmium (UCd), as well as a previously published dose-response relationship between UCd and GFR. Cadmium-related incidence rate, calculated as the change in the prevalence during a one-year period, were used to compute the mortality and DALY in all WHO regions. It is estimated that dietary cadmium would result in a median of 12,224 stage 4 and stage 5 new CKD cases per year worldwide, resulting in 2064 global deaths and 70,513 DALYs. These data translate into a median global burden of 1.0 DALY per 100,000 population, which account for 0.2% of the global DALYs of CKD. While these results suggest that the overall impact of dietary cadmium exposure on global CKD is low, they do indicate that reasonable efforts to reduce dietary exposure will result a positive public health impact. This would be particularly the case in areas with elevated levels of dietary cadmium. Highlights • Global burden of chronic kidney disease (CKD) from dietary cadmium was estimated. • CKD incidence was simulated based on the impact of cadmium on renal function. • Disability-Adjusted Life Years (DALYs) were modeled based on CKD incidence. • Dietary cadmium would result in 0.2% of the global CKD burden. [ABSTRACT FROM AUTHOR]