EAST CALCUTTA WETLANDS AS A SINK OF INDUSTRIAL HEAVY METALS: A PIXE STUDY

Abstract

Industrial wastes are considered as critical factors for disturbing natural ecosystems. The East Calcutta Wetlands, a Ramsar site in West Bengal, India, receives composite industrial effluents, subsequently bringing various kinds of heavy metals throughout the year. This wastewater is being utilized by the local people for pisciculture. The present investigation was carried out to study 1) elemental distribution various components of the wetland and 2) potentiality of water hyacinth in metal amelioration. Water and sediments were collected from four different spots along a wastewater-carrying canal having a stretch of 40km from the source point to the final confluence with river and from the wastewater fed fishpond. Fish (three common carps viz. Labeo rohita, Cirrhinus mrigala and Oreochromis niloticus) and water hyacinth were collected from fishpond mentioned above. Samples were analyzed by PIXE with 3MeV tandem Pelletron. Cr , which is a known metal contaminant of tannery effluent, was detected along with S , K , Ca , Ti , V , Mn , Fe , Ni , Cu , Zn , As , Br , Rb , Sr , Zr . Variable concentrations of some elements like Ca , Fe , Zn in different fish organs was noted in the experiment. Accumulation of Cr , Cu from the water bodies by water hyacinth suggesting their crucial role in heavy metal amelioration.