Occurrence and spatial distribution of metals and arsenic in groundwater sources of Punjab (India), and their health risk assessment

In the present investigation, groundwater samples (n = 508) collected from northern, central, and southern Punjab were analyzed for the detection of potentially hazardous metals (Pb, Cd, Ni, Cr) and As using atomic absorption spectrometer. Lead was observed as a predominant contaminant with 167 (32.8%) samples exceeding the permissible limit, followed by As, with 19 (3.7%) samples above the limit set by WHO. Spatial variation for the occurrence of metals showed statistically significant levels of Ni and Cr in groundwater from central Punjab, and As from northern Punjab. Assessment of health risks to these pollutants revealed As as a noxious pollutant, with hazard indices and carcinogenic risks significantly higher than the recommended limits in the three regions; and hence, posing a serious threat to the study population. Also, the risk values were higher for children than adults, indicative of their higher susceptibility to the ill-effects of these pollutants.