Groundwater pollution has emerged as a significant water crisis in various regions around the globe. Groundwater serves as a crucial source of water for human consumption and agricultural activities in the Sichuan Basin where groundwater quality has yet to be concentrated. A total of 41 groundwater samples were collected from domestic wells in Suining city of the Sichuan Basin, which were used for analyzing the hydrogeochemical processes and suitability for irrigation and drinking purposes. In the study area, groundwater samples belonged to the HCO₃-Ca type. Hydrochemical compositions were dominated by carbonate and silicate mineral dissolution with positive cation exchange. Agricultural activities and urban sewage were the primary sources of NO₃⁻ pollution. The irrigation water quality index (IWQI) was calculated using electronic conductivity (EC), Na⁺, Cl⁻, HCO₃⁻, and sodium adsorption ratio (SAR). The IWQI values showed that the suitability of groundwater irrigation was generally good and presented the decreasing trend southeastwardly. According to the entropy-weighted water quality index (EWQI), the groundwater quality for drinking purposes was generally good. However, there were some local areas with poor water quality concentrated in the southeast part. According to the human health risk (HHR) model, the groundwater was deemed safe for adults and children. However, for infants, the nitrate level in the groundwater remained high and posed potential health risks. The combined IWQI and EWQI evaluation served as a valuable reference for the utilization of the groundwater resource in the Sichuan Basin, as well as other comparable regions worldwide.

Contamination with potentially toxic elements (PTEs) frequently occurs in surface water in coal mining areas. This study analyzed 34 surface water samples collected from the Yunnan–Guizhou Plateau for their hydrochemical characteristics, spatial distribution, source apportionment, and human health risks. Our statistical analysis showed that the average concentrations of PTEs in the surface water ranked as follows: Fe > Al > Zn > Mn > Ba > B> Ni > Li > Cd > Mo > Cu > Co > Hg > Se > As > Pb > Sb. The spatial analysis revealed that samples with high concentrations of Fe, Al, and Mn were predominantly distributed in the main stream, Xichong River, and Yangchang River. Positive matrix factorization (PMF) identified four sources of PTEs in the surface water. Hg, As, and Se originated from wastewater discharged by coal preparation plants and coal mines. Mo, Li, and B originated from the dissolution of clay minerals in coal seams. Elevated concentrations of Cu, Fe, Al, Mn, Co, and Ni were attributed to the dissolution of kaolinite, illite, chalcopyrite, pyrite, and minerals associated with Co and Ni in coal seams. Cd, Zn, and Pb were derived from coal melting and traffic release. The deterministic health risks assessment showed that 94.12% of the surface water samples presented non-carcinogenic risks below the health limit of 1. Meanwhile, 73.56% of the surface water samples with elevated As posed level III carcinogenic risk to the local populations. Special attention to drinking water safety for children is warranted due to their lower metabolic capacity for detoxifying PTEs. This study provides insight for PTE management in sustainable water environments.

Intense anthropogenic activities pose a serious threat to groundwater quality in urban areas. Assessing pollution levels and the health risks of trace elements within urban groundwater is crucial for protecting the groundwater environment. In this study, the heavy metal pollution index (HPI) and health risk assessment were conducted to analyze trace element pollution levels and the non-carcinogenic and carcinogenic risks of groundwater resources in Sichuan Basin, SW China, based on the hydrochemical results of 114 groundwater samples. The HPI results displayed that 14.92% of groundwater samples were contaminated, primarily attributed to anthropogenic influence. The health risk assessment indicated that children faced the highest non-carcinogenic risk while adults had the highest carcinogenic risk. The Monte Carlo simulation further enhanced the reliability of the health risk model. A sensitivity analysis indicated that Pb was the most sensitive element affecting both non-carcinogenic and carcinogenic risks. The achievements of this research would provide a basis for groundwater management in urban areas.