[Source Analysis and Health Risk Assessment of Heavy Metals in Groundwater in the Northeast of Nanchang City]

Heavy metal pollution in groundwater is a serious threat to ecological security and human health. High arsenic, iron, and manganese groundwaters are widely distributed in the Poyang Lake Plain in the middle reaches of the Yangtze River. Urbanization and anthropogenic activities have further aggravated heavy metal pollution in groundwater. Source analysis and health risk assessment of heavy metals will provide a scientific basis for the precise prevention and control of heavy metal pollution in groundwater and the health management of residents in this area. In this study, the northeast of Nanchang City,the central city of Poyang Lake Plain,was selected as the study area,and 94 groundwater samples were collected. The PMF and health risk assessment models were used to analyze and evaluate the pollution sources and health risks of heavy metals in groundwater in the study area. The results showed that：① The mean concentration of heavy metals in groundwater followed the order of Mn>Fe>As>Zn>Al>Cd>Pb>Cu>Hg； the average concentrations of Mn, Fe, and As exceeded the corresponding standard limits； and the spatial distributions of the heavy metals were quite different. ② Source analysis results showed that the mixture of natural and agricultural sources, transportation emissions, waste incineration, and mineral dissolution were the major heavy metal sources, among which the contributing rate of the mixture of natural and agricultural sources was the highest （80.1%）. ③ The health risk assessment showed that the risk of the drinking water pathway was much higher than that of the skin infiltration pathway. The non-carcinogenic health risk （HI） was mainly caused by As through the drinking water pathway, and the non-carcinogenic HI to both children and adults in the study area was higher than the safety level （HI>1）. The carcinogenic risk （CR） caused by As in adults through the two pathways and in children through the drinking water pathway, and the carcinogenic risk caused by Cd in children through the drinking water pathway were all higher than the maximum acceptable risk level （1E-04）. For drinking water safety, the concentrations of As and Cd should be controlled before drinking.