Heavy metal pollution assessment of groundwater and associated health risks around coal thermal power plant, Punjab, India

Coal thermal power plants are critical sources of heavy metal pollution in groundwater with a significant health hazard. The current study assessed the seasonal (pre and post-monsoon) concentration of aluminum, arsenic, iron, cobalt, manganese, nickel, copper, chromium, cadmium, lead and zinc concentrations in groundwater along with heavy metal pollution index and human health risks. Further, multivariate statistical approaches i.e. correlation, principal component analysis and hierarchical cluster analysis were used to estimate the groundwater's interactions with heavy metals to know their possible sources of contamination. The results showed the mean higher concentration (mu g/L) for aluminum (387.65, 399.184), arsenic (11.368, 17.288), lead (7.92, 9.59), iron (126.22, 272.24) and manganese (248.69, 825.82) throughout both seasons than the standard acceptable limits of national and international agencies. Considering the heavy metal pollution index, the mean value was noticed less than the critical value (> 100) for pre-monsoon (19.92) and post-monsoon season (44.42), denoting low-level pollution. Concerning health risks, arsenic, lead, manganese and zinc were the most significant metals causing health hazards with hazard index (105) exceeding the United States Environmental Protection Agency's standard limit and affecting children's population more than adults. Further, high values of toxic metals were noticed during the post-monsoon season. Besides, multivariate analysis showed that anthropogenic and natural activities are attributed to metal pollution. The present study suggests unsuitability of groundwater for drinking purposes as this can cause a potential health risk. Hence, the study area needs routine groundwater quality monitoring as it is susceptible to heavy metal contamination. [GRAPHICS] .