Heavy metal contamination and exposure risk assessment via drinking groundwater in Ain Azel territory, north-eastern Algeria

This study examined the degree of heavy metal contamination of Ain Azel territory in north-eastern Algeria. The groundwater quality was evaluated using water samples collected from 11 localities during May 2018. Thirteen physicochemical parameter values including temperature (T), pH, electric conductivity (EC), total dissolved solids (TDS), calcium (Ca 2+ ), magnesium (Mg 2+ ), sodium (Na + ), potassium (K + ), bicarbonates (HCO 3 − ), sulfates (SO 4 2− ), chloride (Cl − ), and nitrates (NO 3 − ) were recorded. Six heavy metals such as iron (Fe), copper (Cu), zinc (Zn), manganese (Mn), chromium (Cr) and lead (Pb) were analyzed using atomic absorption spectrophotometer (AAS). All the results were compared with WHO standard for drinking water quality. Also, the data were used to estimate the pollution evaluation indices (HPI, HEI, C d ), which indicated that 63.63% of the water samples had high HEI value and 72.72% of the total analyzed samples had high C d values, indicating high contamination in these samples. The high values of health risk assessment parameters (ADD, HQ, CR) for the groundwater samples predicted possible health risks to the local people by drinking metal-rich groundwater. Principal component analysis unconnectedly grouped heavy metals and physicochemical characteristics of groundwater and the calculated pollution indices. This correlation indicated that chromium and lead were responsible for the high values of HPI, HEI and C d obtained in this study. Therefore, there is lead and chromium pollution in the groundwater of the study area.