Hydrochemical characteristics, water quality, and probabilistic health risk assessments of groundwater in Caraveli Province, South Peru

Despite its scarcity, groundwater in Marcona’s catchment area represents the primary source of water for the local population of Caraveli Province, Peru. In this study, hydrochemical analyses, Entropy Water Quality Index (EWQI) evaluations, and health risk assessments (HRAs) were conducted to determine the quality and probabilistic health risks of groundwater. The results indicated that the hydrochemistry of groundwater was primarily influenced by evaporation, water–rock interactions, and anthropogenic activities. The recharge zone was a relatively suitable source for irrigation. Groundwater within the catchment zone failed to meet certain irrigation standards, and groundwater from the remaining zones was not suitable for irrigation. EWQI values indicated that approximately 41.9% of the samples were suitable for drinking. Notably, the sensitivities of Fe, Cl⁻, Na⁺, NO₃⁻, and SO₄²⁻ were 13.18%, 2.02%, 1.71%, 1.28%, and 1.23%, respectively. Probabilistic noncarcinogenic HRAs determined the health risks associated with NO₃⁻, Fe, and Mn to be 9.3% for adults and 31.9% for children. These noncarcinogenic health risks were primarily attributable to Fe and NO₃⁻. In summary, this study explores the mechanism underlying water quality and health risks in arid regions, underscoring the importance of enhancing public awareness regarding the long-term consequences of consuming contaminated groundwater.