In order to investigate the distribution characteristics and the human health risks of 12 metals in drinking water sources from the Luhun Reservoir, Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn concentrations in 46 water samples collected from the reservoir in 2016 were measured and analyzed. The health risks caused by metals were assessed by using a human health risk assessment model. The results showed that the maximum concentration of Al (200.27 μg·L-1) and all concentrations of Mo (151.42-170.69 μg·L-1) in drinking water from the Luhun Reservoir exceeded the Environmental Quality Standards for Surface Water (GB 3838-2002) and Standards for Drinking Water Quality (GB 5749-2006) by 4.35% and 100%, respectively. A distinct spatial heterogeneity was found in the metal distribution, and the region with the highest metals concentrations was located southwest (upstream) and northeast (downstream) of the reservoir. The results of a health risk assessment indicated that children had greater health risks than adults. The health risks for metals through drinking were all higher than the values caused by dermal contact. Carcinogenic risks caused by Cr and As exceeded the maximum allowance levels (5×10-5 a-1) by 100% and 3.80%, respectively, and Cr accounted for 85% of the total carcinogenic risks. The non-carcinogenic risks of the metals (10-12-10-7 a-1) decreased in the order of Al > Mo > Cu > Pb > Ni > Hg > Fe > Zn > Mn, which had levels two to seven orders of magnitude lower than the maximum allowance levels.
Keywords: Luhun Reservoir; distribution characteristics; drinking water source; health risk assessment; metals.