dc.description.abstract | Aim of this study was to build a strong information and statistical based assessment and comparisonof long term heavy metal contamination in sediments some major estuaries across Indian coast. About70 published works were studied and metal concentrations was absorbed from 52 studies whereappropriate information was available. Based on it, Enrichment Factor (EF) and I Geo (Geoaccumulation Index) were calculated for further analysis. In the Ganga estuary, Enrichment Factors(EF) for metals such as Pb, Cu, Zn, Al, and Mn remain low (EF < 2), while Cd exhibits noticeablepollution (EF reaching up to 25.1 in 2008). The Godavari estuary shows extreme contamination,particularly for Cd, with EF values rising alarmingly from 1761.46 in 1996 to 7504.63 in 2016, andthe Cauvery estuary, with EFs exceeding 20 for Pb, Cu, Ni, and Zn (e.g., Zn, EF = 224.11), alsoreflects severe anthropogenic impact. However, on the west coast, estuaries such as Ulhas displayhigh enrichment for Cd (EF 4.09-18.24), while the Periyar estuary records consistently high Cdcontamination, with EFs up to 111.68 and Igeo values up to 6.67. While with respect to Igeo, Ulhasestuary was found to be most frequently contaminated. The findings highlight that eastern estuariesare generally more heavily impacted, particularly with Cd, Pb, and Zn, often linked to industrialdischarge, agricultural runoff, and mining activities. Even after excluding EF of Cd due to someexceptionally high values in eastern coast, Mean EF with respect to all other metals of Eastern coastestuaries (12.63) is much higher than that of western coast estuaries (1.84). This study underscoresthe need for focused interventions to mitigate heavy metal pollution, especially in eastern estuarineregions where contamination levels are particularly elevated. with distinct variations across the easternand western coastlines. | |