Health risk assessment of Fluoride and Cadmium enrichment in rural drinking groundwater in Shanxi Province, China

Excessive levels of Fluoride (F⁻) and Cadmium (Cd) in drinking groundwater may pose health risks. This study assessed the health risks associated with F⁻ and Cd contamination in rural drinking groundwater sources in Wutai County, Shanxi Province, China, to support population health protection, water resource management, and environmental decision-making. Groundwater samples were collected and analyzed, and a Human Health Risk Model (HHRA) was applied to evaluate groundwater quality. The results showed that both contents of F⁻ and Cd in groundwater exceeded the Class III limits of China's national groundwater quality standard (GB/T 14848—2024). Fluoride levels met the Class V threshold, with enrichment area mainly located in the east part of the study area. Cadmium levels reached Class IV, with elevated concentrations primarily observed in the western and northwestern regions. Correlation analysis revealed that F⁻ showed weak or no correlation with other measured substances, indicating independent sources. Health risk assessment results indicated that F⁻ poses potential health risks to rural residents, while cadmium, due to its relatively low concentrations, does not currently present a significant health risk. Among different demographic groups, the health risk levels of F⁻ exposure followed the order: Infants >children >adult females >adult males. The findings highlight that fluoride is the primary contributor to health risks associated with groundwater consumption in the study area. Strengthened monitoring and prevention of F⁻ contamination are urgently needed. This research provides a scientific basis for the prevention and control of fluoride pollution in groundwater and offers practical guidance for safeguarding drinking water safety in rural China.