Assessment of heavy metal pollution level, ecological and human health risks in surface water of Narmada River, India

Abstract

The present research focuses on the evaluation of selected heavy metals (Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd, & Pb) in the upper stretch of the Narmada River in central India to detect the pollution status, degree of heavy metals contamination, and threat to human health. The concentration of the selected heavy metals was in the order of Al > Fe > Zn > Mn > Cr > Ni > Cu > Pb > Cd and Al > Fe > Zn > Mn > Cr > Ni > Pb > Cu > Cd for pre-monsoon and post-monsoon season respectively. Further indices like the heavy metal evaluation index (HEI) indicated that the water of the Narmada River was medium polluted, heavy metal pollution index (HPI) categorized the water as moderately to heavily polluted. The nemerrow pollution index (NPI) classified 8% of sampling sites as low polluted, 42% as medium polluted, and 50% as highly polluted in pre-monsoon. Similarly, for the post-monsoon, NPI classified 42% of sampling sites as low polluted, 33% as medium polluted, and 36% as highly polluted water. Total hazard risk indicated a non-carcinogen risk for children and adults. In both seasons, based on human health risk assessment, ingestion of heavy metals contaminated water especially with Cr was identified to be highly prone to cancer risk. This research will aid in the development of effective planning and policies for enhancing river water quality and reducing ecological and human health risks. Graphical Abstract: (Figure presented.) © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.