Ecological and Health Risk Assessment of Nitrates and Heavy Metals in the Groundwater of the Alluvial Area of the Danube River near Kostolac Basin, Serbia

Water-quality indicators and trace elements were measured in the alluvial area of the Kostolac Basin, Serbia. The results revealed that the groundwater was naturally neutral, with a mean conductance of 920.10 μs/cm. The primary factors contributing to the decline in the groundwater quality in the researched area were electrical conductivity (EC), NO3−, SO42−, Cd, and Pb; the water samples were deemed unfit for human consumption and the water was classified as having impaired quality. A Pearson correlation matrix, a principal component analysis (PCA), and a cluster analysis (CA) were applied to identify the pollution source and factors controlling the groundwater quality and the results indicated that both natural and anthropogenic factors influenced the groundwater of the studied area. The Nemerow pollution index indicated medium to high pollution levels along with the degree of contamination. A health risk evaluation was conducted to determine the non-carcinogenic risks posed by nitrates and heavy metals from oral consumption and skin contact in the researched area. Nearly all monitoring sites had hazard quotients (HQs) below 1, suggesting that potential concerns might be negligible. However, children showed the highest exposure levels, with HQs for nitrates at 2.26 and for lead (Pb) at 2.515. No carcinogenic risk from oral lead (Pb) exposure was found in any sample.