Human health risk assessment of chromium in drinking water: A case study of sukinda chromite mine, Odisha, India

Abstract

The present study aims to evaluate human health risk of Cr(VI) and Cr(III) via oral and dermal exposure of drinking water in groundwater samples of nearby Sukinda chromite mine. The risk assessment of each location was carried out using mathematical models as per IRIS guidelines and the input parameters were taken according to the Indian context. The concentrations of TCr and Cr(VI) were found in the range of 48.7-250.2 and 21.4-115.2µlg/l, respectively. In the maximum locations, TCr and Cr(VI) concentrations were found 2.3-6 times and 2.1-11.5 times higher, respectively, than the permissible limit as per standard statutory bodies. The total cumulative average cancer risk and non-cancer risk (Hazard Quotient) was found 2.04E-03 and 1.37 in male and 1.73E-03 and 1.16 in the female population, respectively, which indicated ‘very high’ cancer risk and ‘medium’ non-cancer risk as per USEPA guideline. Male population was found 1.2 times higher cancer and non-cancer risk than females, because of the higher water ingestion rate in male. The obtained health risk via dermal route was found 6 times lesser than the oral ingestion due to very less dermal exposure time (0.58 h/days). As a consequence, ‘high’ cancer risk also recorded in one of the locations where TCr concentration was within permissible limit which is because of the higher proportion of bioavailable Cr(VI). Sensitivity analysis of input parameters towards cancer and non-cancer risk revealed that Cr(VI) and Cr(III) concentrations were the main predominant parameters followed by exposure duration, body weight, average time, and dermal slope factor.