Evaluating Groundwater Potability and Health Risks from Nitrates in the Semi-Arid Region of Algeria

Abstract

In the semi-arid region of Ain Ouassera, Algeria, groundwater from the lower cretaceous aquifer (LC) serves as an essential resource for drinking and various other requirements. This study focuses on evaluating the suitability of water for domestic use and examining the non-carcinogenic health risks associated with consuming water containing high levels of nitrates. To explore these dimensions, the research utilizes the water quality index (WQI) method and the health risk assessment (HRA) model as formulated by the USEPA. The findings categorized the groundwater quality predominantly as "poor" for consumption purposes, with nitrate concentrations ranging from 14 to 112 mg/L, where 40% of the samples exceeded the World Health Organization's (WHO) permissible limit (> 50 mg/L). Furthermore, the health risk analysis indicated that 76.67% of the samples for children and 70% for adults surpass the safety thresholds (QH > 1), signifying a significant risk to the local population. The study also uncovered that the hydrochemical characteristics of the groundwater reflect a mixed composition (CaMgCl) and that mineralization is mainly attributed to the dissolution of carbonates, sulfates, and halite, alongside inverse ion exchange processes and anthropogenic influences. These findings underscore the urgent need for improved groundwater management measures and risk mitigation strategies in the Ain Ouassera region.