Evaluating The Current Quality Status and Potential Health Risk of Heavy Metals in Groundwater Near a Mining Site in Ha Trung, Ha Long, Quang Ninh Province, Vietnam

Abstract

In this study, groundwater quality and the human health implications of heavy metal contamination near a coal mining site in Ha Trung, Ha Long, Quang Ninh Province, Vietnam, were examined. Ten household wells were sampled during both the wet and dry seasons (n = 20) and analyzed using multivariate statistical and quantitative methods. The results indicated that the concentrations of heavy metals (Mn, Hg, Fe, Se, Cu, Ni, Zn, Cd, Pb, and As) increased during the dry season. Specifically, the levels of Pb, Fe, and Se surpassed Vietnam’s technical regulations on domestic water limits in both seasons, raising concerns about the potential health impacts on local communities. Health risk assessment revealed that children face greater exposure risks than adults do, with As and Pb being the main contributors posing the greatest noncarcinogenic and carcinogenic risk. Noncarcinogenic risk assessments revealed that 90% of the sampling sites exceeded safe exposure levels for both adults and children, indicating a potential noncarcinogenic health risk from groundwater heavy metal exposure in both age groups. The carcinogenic risks associated with As and Pb at all the sampling sites were much greater than the United States Environmental Protection Agency acceptable risk range of 10^-6–10^-4 for both age groups in both seasons, suggesting that As and Pb in groundwater pose significant carcinogenic risks to the local population.