Occurrence, toxicity load, pollution index and health risk assessment of trace elements in drinking water of two catchments in North-western Himalayas

The study focuses on the analysis of trace metals in drinking water from the Ganderbal and Budgam districts of Jammu and Kashmir. We have used high-resolution inductively-coupled plasma mass spectrometry (HR-ICP-MS) to measure the concentrations of 31 trace metals in the water samples. The measured concentrations were then compared with the permissible limits set by the United States Environmental Protection Agency (USEPA), Bureau of Indian Standards (BIS), and World Health Organization (WHO). The results of the study indicate that arithmetic mean of several trace elements, including aluminum (Al = 781), chromium (Cr = 139), manganese (Mn = 41.86), nickel (Ni = 25.89), molybdenum (Mo = 1.30), cadmium (Cd = 36.86), and mercury (Hg = 67.65), in mu g l-1 were found to have concentrations higher than their respective permissible limits. On the other hand, the arithmetic mean of elements, such as beryllium (Be = 0.14), boron (B = 32.72), iron (Fe = 233), cobalt (Co = 1.79), copper (Cu = 10.71), arsenic (As = 0.93), selenium (Se = 3.13), strontium (Sr = 257), zinc (Zn = 43), antimony (Sb = 1.44), barium (Ba = 28.56), gold (Au = 0.91), and lead (Pb = 0.91) in mu g l-1, had concentrations below the permissible limits recommended by USEPA, BIS, and WHO. To assess the toxicity of the heavy metals in the study area, we calculated the Heavy Metal Toxicity Load (HMTL) for each metal. Based on these calculations, we concluded that only cadmium (Cd) and chromium (Cr) need to be removed from drinking water to ensure safety. The study also conducted a health risk assessment for children and adults based on the measured concentrations of heavy metals. The assessment considered the ingestion and dermal contact routes of exposure. The Hazard Index (HI), which indicates the non-carcinogenic health effects, exceeded unity for only one element, cadmium (Cd), in the children and adult groups. This suggests potential non-carcinogenic health risks associated with the ingestion of water and dermal contact. Additionally, the potential carcinogenic risk of cadmium (Cd) and arsenic (As) was identified and recommended for further attention. The study further evaluated the Heavy Metal Pollution Index (HPI) to assess the overall quality of drinking water in the study area. The HPI results indicated that the quality of drinking water was good, and the pollution levels in the study area were low. Overall, the findings of this study provide valuable information for water resource development and supply agencies. The results can be used as a baseline for future research and monitoring efforts in the region.