Evaluation of possible health risks associated with groundwater pollution at Kombolcha, a north-central Ethiopian industrial town in the Awash River basin

Groundwater contamination from intensive agricultural and industrial activity can lead to deteriorated drinking water quality that poses serious health threats for humans. The intention of the study was to appraisal the level of groundwater pollution and the potential risks it could pose to the residents of Kombolcha Town, an area with significant industrial and agricultural activity. Samples were obtained from seventeen groundwater wells in August 2021 and examined with standard methods. The groundwater comprehensive and indices for irrigation were calculated to evaluate the appropriateness of water quality for various purposes. A USEPA model was applied to estimate human health risks from polluted groundwater. Results revealed that all hydrogeochemical characteristics and heavy metals, with the exception of chromium, were within Ethiopian and World Health Organization drinking water guideline. Groundwater quality pollution index results for drinking demonstrated that 5.88% of water samples were evaluated as very good, whereas 94.12% of water samples were rated excellent. Ca-HCO3 facies make up 53% of samples, and Ca–Mg–Cl facies account for the remaining samples. Total non-carcinogenic risks to health for males extended from 0.35 to 2.39, for women from 0.38 to 2.59, and for children from 0.49 to 3.38. Cancer risks ranged from 0 to 1.6 × 10−3 for men, 0 to 1.74 × 10−3 for females, and 0 to 2.24 × 10−3 for children. These results indicate that children in this region suffer more risks for health than adults. The study concluded that to safeguard water quality, reduce threats to health, and more efficiently use the groundwater resource, prompt and efficient actions on agricultural and industrial practices must be taken in the research area.