Spatial distribution, formation mechanism, and health risk assessment of high-fluoride groundwater at the largest antimony mine in Hunan Province, China

To date, few systematic studies have been conducted of the spatial distribution, formation mechanism, and health risks of high-fluoride (F−) shallow groundwater in humid and semi-humid areas of the Xikuangshan antimony mine, Hunan Province, China. In this study, during March and April 2022, a total of 39 shallow groundwater samples were collected and analyzed using factor analysis, principal component analysis, and health risk assessment. F− concentrations in the shallow groundwater were found in the range of 0.08–15.00 mg/L (mean: 1.21 mg/L), with 25.64% of the samples having F− concentrations higher than in the Chinese national standard for drinking water (1.00 mg/L). Principal component analysis revealed that the main source of F− in the shallow groundwater samples is cation exchange, accounting for 73.40%, followed by the dissolution and precipitation of F-bearing minerals (15.10%) and human influence (11.50%). Among different age groups, children had the highest percentage of individuals (36.38%) with an F− intake above the health risk quotient safety limit, followed by adult males (23.12%), teenagers (22.21%), and infants (21.22%). The findings of this study will contribute to devising strategies for the provision of safe drinking water and the management of the geological environment.