Integrating Multi-Index and Health Risk Assessment to Evaluate Drinking Water Quality in Central Romania

Chemical contaminants in drinking water represent a widespread threat to human health, making water quality monitoring an essential mitigation measure. This study aimed to assess the quality of drinking water by conducting comprehensive multi-year seasonal monitoring at seven distribution points in central Romania, determining the spatial and temporal trends of relevant physical parameters (pH and electrical conductivity) and chemical contaminants (NO2, NO3, NH4, Cl, and SO4). The pollution degree was evaluated using the pollution index and the overall pollution assessment index. The principal component analysis attributed over 60% of water quality variance to NO2, NO3, and NH4 pollution, linked to incomplete nitrification or external loading, such as agricultural practices. Additionally, a human health risk assessment was performed according to U.S. EPA guidelines, calculating the chronic daily intake, hazard quotient, and hazard index for nitrogen compounds via oral and dermal exposure pathways for both adults and children. The results showed significant seasonal fluctuations in nitrogen compounds and electrical conductivity. The pollution indices classified the water bodies across a spectrum from “light” to “significant” pollution degrees. The health risk assessment revealed that NO3 was the primary risk driver, with hazard index values exceeding the threshold of one in specific locations and seasons, indicating potential adverse health effects, particularly for children.