[Distribution Characteristics and Health Risk Assessment of Metal Elements in Groundwater of Longzici Spring Area]

Longzici Spring is an important water source for industry, agriculture, and urban life in Linfen City. With the improvements in public environmental health awareness, it is particularly necessary to study the health risk of posed by metal elements in groundwater. In this study, 43 groundwater samples from Longzici Spring area were analyzed for ten metal elements (As, Cd, Hg, Al, Pb, Co, Mn, Fe, Cu, and Ni). The distribution and health risk of these metal elements in the groundwater were studied using multivariate statistical analysis and a health risk assessment model. The results show that metal elements can be ranked, from high to low, by their average concentrations in groundwater in the following order: Fe, Al, Mn, Ni, As, Cu, Co, Pb, Hg, and Cd. The concentration of Al, Mn, Fe, and As exceed the limit for class Ⅲ water, as defined in the quality standard for groundwater (GB/T 14848-2017). Different types of groundwater in the spring area showed different metal contents. The quality of karst spring water was good, reaching the standard for drinking water, while mine drainage water exceeded the standard for drinking water, with the highest metal concentration (60%) and the worst water quality. Multivariate statistical results show that Pb, Ni, Co, Cd, Mn, and Cu concentrations were mainly affected by the geochemical background, while Al, Fe, Hg, and As concentrations were closely related to human mining activities under the unique geological background of Shanxi Province. The health risk assessment showed that the different types of groundwater could be ranked by the annual total health risks, posed by metal elements to adults and children through drinking water and skin infiltration, as follows: karst well > non-karst spring > non-karst well > karst spring. The health risks mainly came from drinking water, while health risks through skin infiltration would not cause obvious harm to the human body. The metal element causing the greatest health risk in spring groundwater was As, which should therefore be controlled in the utilization of water resources, especially in children's drinking water.