Heavy metals exposure, carcinogenic and non-carcinogenic human health risks assessment of groundwater around mines in Joghatai, Iran

Contamination of surface and groundwater resources to heavy metal due to mining activities is a worldwide major issue because of its probable health risks to local residents. In the present research, we measured the concentrations of As, Cd and Cr in 26 water samples collected from 13 rural areas in the vicinity of mines in Sabzevar, Iran, during January 2019 and estimated potential health risks among local residents. Heavy metal concentrations were analysed using an atomic absorption spectrometer and compared with guidelines set by the WHO. The results showed that As and Cr concentration in drinking water of rural areas in the vicinity of mines were estimated to be in the range of 0.0152 to 0.0220 and 0.0194 to 0.1806 mg/L, respectively, which exceeded the drinking water guidelines recommended by WHO. For cadmium, the concentrations ranged from 0.0003 to 0.0018 mg/L. Total HI (hazard index) values were above one in drinking water of all villages and generally, total HI values for children were much higher than those of adults in each studied area. The total cancer risk values of metals (sum of As, Cd and Cr) for children and adults in all the villages were above the USEPA limit. The CR (carcinogenic risk) values for both children and adults through the oral pathway were found in order of As>Cr>Cd. The findings of health risk assessment of groundwater near the mining area could be valuable for proper management of water resources in the rural areas in particular and to the other mining areas in general.

Automated summary

Contamination of surface and groundwater resources with heavy metals due to mining activities poses a major health risk to local residents worldwide. This research in Sabzevar, Iran, measured the concentrations of As, Cd, and Cr in water samples from rural areas near mines and assessed potential health risks. The concentrations of As and Cr in drinking water exceeded WHO guidelines, while Cd levels were within acceptable range. Hazard index values were all above one in all villages, with higher values for children. The total cancer risk from metals exceeded USEPA limits for both children and adults. The findings of this study are important for managing water resources in rural areas and other mining regions.