Evaluation of the Chemical Composition of Drinking Water from Different Sources

Abstract

This study evaluated the chemical quality of drinking water from 157 sources across northern, central, and southern regions of the Republic of Moldova, sampled during two seasonal campaigns. Significant differences were observed between source types, with wells showing the highest contamination levels: 35.7% of samples exceeded the nitrate limit (50 mg/L), 33.1% exceeded the sulfate limit (250 mg/L), and 23.6% surpassed the TDS threshold (1500 mg/L). Artesian boreholes frequently exhibited elevated fluoride and sulfate concentrations linked to geological formations, while public supply and filtered water were largely compliant. Statistical analysis using non-parametric tests and Principal Component Analysis (PCA) confirmed distinct hydrochemical regimes and a clear mineralization gradient across sources. These findings highlight potential public health risks, especially for rural populations relying on decentralized sources. The study underscores the need for regular monitoring and improved management of groundwater resources, although its cross-sectional design and lack of geospatial data limit the ability to assess temporal or spatial trends.