Exposures and Health Risks Associated with Elements in Diets from a Gold Mining Area.

Abstract

There has been a concern of metal contamination from the mining areas which could expose the population to toxic metal through consumption of food products in the regions. Therefore, the study was conducted to analyze 18 elements using X-ray fluorescence analyzer and to assess for metal exposure through dietary intakes. Dietary recall survey instrument was used to collect consumption, demographic, and anthropometric data from 308 consumers in life-stage groups: toddlers, adolescents, and adults. Cassava, maize, rice, tomato, and yam indigenous diet samples (66) from the gold mining regions of Ghana were obtained by purposively sampling from street vendors. Principal component analysis was used to apportion pollution source. Health risks due to dietary elements were quantified using US EPA probabilistic protocols for cancer and non-cancer disease endpoints. Deficiency and overage risks of essential elements were tested against reference nutrient intakes. The element-diet-location mode of principal component analysis separated cassava and maize diets as significant vehicles for both essential and toxic elements apportioned to mining pollution source. The chronic daily intake trend revealed a preponderance for arsenic (maize: toddlers 0.009, adolescents 0.025 adults 0.010mg/kg-d) and lead (maize: toddlers 0.009, adolescents 0.026, adults 0.010mg/kg-d) exposure through maize diets compared to cassava diets. The hazard quotient showed (HQ > 1) life-stage risk differentiation for barium, although there were cumulative and pervasive health risks for all age groups based on the hazard index (Ag, Ba, Cd, Co, Hg, Mn, Mo, Sb, Sn, Sr, U, V, W, and Zr). The likely cancer risk (mode) for all life-stage groups (3 × 10-6-1 × 10-2) were also high in that they exceeded the 1 × 10-6 safety threshold. The modal margin of exposure (MoE < 1) alerted high public health concern due to lead-induced toxicities among all life-stage groups through all diet vehicles. Regarding nutritional adequacy, there were possible overage risks associated with selenium, including deficiency risks for calcium, potassium, and zinc for all life-stage groups. Toddlers and adolescents were susceptible to iron deficiency risks through cassava diets and iron overage risks through maize diets.