Comprehensive analysis of heavy metal contamination in the Mandakini (Payaswini) river: Multivariate and index-based...

Contamination of drinking water sources with heavy metals poses a significant threat to humanity due to their complex behavior, high toxicity, and ability to infiltrate and accumulate in groundwater. Heavy metals in water samples can lead to various chronic and irreversible health issues. This study was performed to identify the concentration of heavy metals in the Mandakini (Payaswini) River in Madhya Pradesh, India, and to evaluate their potential health effects on the local population. A comprehensive analysis was conducted using the Heavy Metal Pollution Index (HPI), modified Heavy Metal Pollution Index (m-HPI), and chemometric methods, including Principal Component Analysis (PCA) and cluster analysis (CA) to assess contamination levels, identify critical pollutant affecting the water quality, and examine similarities in sampling locations, respectively. Water samples were collected and analyzed for 13 heavy metals at nine rivers and two drain locations. The HPI and m-HPI indices quantitatively assessed water quality, revealing significant heavy metal contamination, especially in downstream regions affected by human activity. Cluster analysis was applied to characterize the highly correlated heavy metals, and PCA was employed to ascertain the primary factors contributing to water contamination. Analysis suggested a high iron (Fe) and manganese (Mn) concentration in both seasons for river and drain samples primarily from untreated domestic wastewater, petroleum waste through petrol pump, and agricultural waste, which may induce significant health hazards, particularly to vulnerable groups. PRACTITIONER POINTS: The spatial and temporal variation in concentration of heavy metals was determined using violin plots and GIS. The cluster analysis suggested identically behaving heavy metals in terms of seasonal variation. The principal component analysis suggests the critical variables and significance of variables affecting water quality. The impact of the consumption of water has been derived on human health.