ABSTRACT Fluoride and nitrogen contamination is a global concern and has been a serious problem in agricultural areas. This study aims to identify the source of fluoride and nitrogen in the groundwater and assess groundwater quality and human health risks in the Guanzhong Plain, northwest China. The results showed that the concentrations were 0.15–4.74 mg/L for F−, 0.02–89.89 mg/L for NO3−-N, and BDL-2.40 mg/L for NH4+-N in groundwater. Distinct area-dependent distributions of fluoride and nitrogen were observed in the study region. Higher F− and NO3−-N concentrations in groundwater were detected in the northern part, and higher NH4+-N levels were observed in the southern part. Water–rock interaction and agricultural activities were the controlling factors for fluoride and nitrogen distribution in groundwater. About 80% of samples are considered to have good water quality with a Water Quality Index (WQI) < 100. Exposure to fluoride and nitrogen through drinking should require more attention. The total non-carcinogenic risks through oral ingestion of groundwater were 0.22–3.19 for adults and 0.51–7.44 for children, respectively. The order of pollutants in the groundwater in terms of their hazard to residents was F− > NH4+-N > NO3−-N > NO2−-N. The findings of this study could provide more insights into groundwater management.
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