Water Quality Assessment of Southwest Punjab Emphasizing Carcinogenic Contaminants and their Possible Remedial Measures (NIH-14_2017_24)

Abstract

The consumption of contaminated water is the main source of human health issues in this century. The south-western districts of Punjab are witnessing high per capita cancer cases, almost twice of national average. Accordingly, this study was undertaken to identify and quantify the carcinogenic contaminants present in the groundwater of the study area, which is the primary source of drinking water. The residents of the study area are quite aware about the issues related to drinking water and are trying to opt for other options for drinking water if available. The study indicated around 23% samples exceeded the maximum permissible limit for TDS. NH4 was observed in more than 75% of samples indicating contamination of water resources and anoxic environment in the aquifer. F concentration exceeded the maximum permissible limit in 19.6% and 31% samples during pre-monsoon and post monsoon respectively. Concentration of B, Fe, Co, Ni, Pb, Be, As, Se, Hg, U, Al, Cr, Cu, Mn, and Zn also exceeded the maximum permissible limit in significant number of samples, however, pesticides were observed below the recommended limits for drinking water. The water samples were observed to be more deteriorated in pre-monsoon period. The cancer-associated risk based on Ni, Pb, As, Hg, U, Cr, Be, Co, Se, Cd, and NO3 was computed and around 83.7% of samples were in the high-risk category during pre-monsoon which got reduced to 61.1% in the post-monsoon period. Removal of U, As, Cr, and Pb from the groundwater samples will result in 93.9% and 98.4% groundwater samples under low-risk category for pre-monsoon and post monsoon period respectively. The concentration of radon in water samples ranged from 11.1 pCi/l to 319 pCi/L and can result in around 58.2 to 1670 deaths/million population/year. The study indicated need for further research on the factors responsible for the dissolution of U and other trace metals in the groundwater for in-situ remediation and estimation of indoor radon concentration for holistic estimated of overall cancer risk.