Lazhar Belkhiri
University of Hadj Lakhdar Batna, Algeria
Title: Evaluation of potential health risk of heavy metals in groundwater using the integration of indicator kriging and statistical methods
Biography
Biography: Lazhar Belkhiri
Abstract
Multivariate statistical methods, geostatistical techniques and human health risk assessment were used to determine the main factors and mechanisms controlling the spatial variation of heavy metals in groundwater and to assess the adverse health effects on the population. Q-mode cluster analysis (Q-mode CA) grouped the sampling wells into two statistically significant clusters based on similarities of groundwater quality characteristics. Two significant factors were extracted by principal component analyses (PCA), explaining 64.19 % of the total variance. These factors were in turn described by the clusters 1 and 2, respectively, resulting from the R-mode CA. PCA and CA revealed significant anthropogenic contributions and water-rock interaction effects of the metals in groundwater. Health risk assessment like chronic daily intake (CDI) and hazard quotient (HQ) indices were calculated for child and adult. The HQ indices of Cd and Pb in child and Al and Fe in adult were found to be higher than the safe limits, posing adverse health hazards and potential non-carcinogenic health risks to the inhabitants. Spatial variability maps using ordinary kriging show that safe zones are mainly concentrated in the west and south-western parts of the study area, while the contamination zones are found to be concentrated in the east, north, and south-eastern parts of the plain. The indicator kriging maps show highly uneven spatial pattern of Pb, Cd, Fe, and Al concentrations. The probability maps show that more than 50% of the total area had the highest probability (0.8-1.0) of exceeding the threshold values for Cd and Pb