Environmental Quantification of Heavy Metals in the Subarnarekha,Estuary and Near-shore Environment,East Coast of India

Abstract

Concentration of heavy metals (Pb, Cd, Hg, Cu, Ni, Co, Cr, Mn and Fe) in the sediments was measured from the river, estuarine and coastal environment off Subarnarekha River, Bay of Bengal. The degree of contamination of the sediments was evaluated through enrichment factor (EF), geo-accumulation index (Igeo) and pollution load index (PLI). The high ER's and Igeo values for Cu and Cr were due to the chromite and copper mines, and Cu ore processing plants situated on the upstream catchments of the river. PLI for Subarnarekha estuary and coastal environments were calculated with respect to world surface rock average, where the site indices are greater than unity. Multivariate statistical analysis like factor and cluster analysis were performed in order to assess the geochemical processes responsible for heavy metal distributions and relationship between stations respectively.