Assessment of surface water quality impacted by upstream artisanal mining in Prek Te area, Cambodia

Mining activities can significantly impact water quality by introducing various contaminants into water sources. The purpose of this study is to assess heavy metal concentrations and other elemental contaminants in water from the Prek Te area across two seasons and evaluate the potential health risks associated with drinking contaminated water. Surface water samples were collected twice in 2023: from March 5 – 11 (dry season) to October 20 – 26 (rainy season). A total of 21 surface water samples were collected from different locations along the Prek Te area. On-site measurements included pH, electrical conductivity, dissolved oxygen, and total dissolved solids, while laboratory analyses determined arsenic (As), chromium, nickel (Ni), copper, zinc, cadmium, and lead concentrations using inductively coupled plasma mass spectrometry. The results indicated that most parameters were within the World Health Organization guidelines and Cambodia Drinking Water Quality Standards, except for As and Ni. During the rainy season, the highest As concentration was 58.1 μg/L, followed by 22.0 μg/L and 10.8 μg/L. Health risk assessments revealed that the hazard index and hazard quotient for children exceeded 1, indicating potential non-carcinogenic health risks. In addition, children exhibited the highest lifetime cancer risk for As (>1.8 × 10−1), followed by women (>1.2 × 10−1) and men (>1 × 10−1). These findings suggest that children are more vulnerable to health risks associated with drinking contaminated water compared to adults. To ensure safe drinking water for communities along the Prek Te area, an urgent monitoring program and appropriate water treatment measures—particularly to remove As contamination—are recommended.