Distribution, exposure, and human health risk analysis of heavy metals in drinking groundwater of Ghayen County, Iran

The concentrations of arsenic (As), chromium (Cr), lead (Pb) and zinc (Zn) and the human health risk of the metals were estimated through drinking water consumption. Totally, 48 samples of groundwater were collected and analyzed during 2019. Health risk indices were estimated using chronic daily intake (CDI), hazard quotient (HQ) and, hazard index (HI), as well as cancer risk (CR). Except for As (66.6% of the areas were above permissible limits), the concentrations of other three heavy metals were within the US EPA and WHO permissible limits. n-ary sumation Sigma HI values in 100% and 75% of the areas were above 1 for children and adults, implying non-carcinogenic risk from sum of heavy metals. Children total cancer risk (CRt) in all areas (except one area with acceptable risk) fell within unacceptable risk. Adults CRt in all areas (except one area with unacceptable risk) were in acceptable risk category. As was the highest contributor to non-carcinogenic and carcinogenic risks both for children and adults. Our results showed that children were more exposed to health risks, due to intake of drinking water containing As, Cr, and Pb in the study areas. The study can provide a basis for local governments to properly manage drinking water quality and provide a reference for water quality management in neighborhood areas.

Automated summary

The concentrations of arsenic, chromium, lead, and zinc in groundwater were analyzed, and their potential health risks were assessed. Except for arsenic, the concentrations of the other three metals were within permissible limits. Children were found to be more vulnerable to health risks. The study provides valuable information for local governments to manage drinking water quality and neighboring areas to control water quality.