Application of Chemometric methods for assessment of heavy metal pollution and source apportionment in Riparian zone soil of Ulhas River estuary, India

A study was carried out to understand the heavy metal pollution status of the riparian zone soil of Ulhas River estuary, Mumbai, India. Soil samples were analyzed for Na, K, Ca, Mg, Mn, Fe, Ni, Co, Cd, Cu and Pb. Heavy metal pollution status study was carried out using Geoaccumulation Index (I_geo) and Pollution Load Index (PLI). Pollution degree (Igeo indices) of different heavy metals were found in the order of Cu>Cd> Ni>Pb>Fe≍Co>Mn. PLI identified the locations depending upon the cumulative load of all these heavy metals and their hot spots. Sources identification and apportionment was done using chemometric data analysis techniques like factor analysis (FA) and factor analysis-multi linear regression (FAMLR) receptor modeling. The study revealed that, chemical weathering of basaltic trap, dug sediment of Ulhas River and erosion of dolomite rich soil are major polluting sources responsible for metal concentrations in the landscape. The hot spot due to the factors 2 lies close to riverine system.