Trace Metal Pollution Research

Contamination with trace metals has become a great concern around the world, especially in developing countries including India (Alagarsamy, 2006). With the rapid industrialization and economic development in coastal region, these metals are to be introduced to aquatic environment (Feng et al., 2004; Romano et al., 2004). Contaminated marine sediments have been recognized as a very important deposit for persistent toxic substances (heavy metals and xenobiotic organic compounds) released into the aquatic environment from various sources. Identification of the natural and anthropogenic sources of heavy metals is an important task in marine pollution research (Esen et al., 2010). Previous studies have shown that human exposure to a high concentration

Therefore, sediments are usually used as an indicator to reflect the environment quality of aquatic systems (Unlu et al., 2008). In order to avoid the pollution of trace metals, it is important to establish the data and understand the mechanisms affecting the distribution of these toxic metals in marine environment. Due to the complexity of the chemical behaviour of metals in the sediment, there has been no widely accepted sediment quality standard so far (Binelli et al., 2008). Some methodologies to assess heavy metal pollution in sediments have been proposed, such as the geoaccumulation index (Igeo), pollution load index (PLI), sediment enrichment factor (EF), contamination factor (CF), etc. These four methods have something in common as they all use heavy metal concentration in the relatively uncontaminated sediment as background value, through comparing the heavy metal concentration in studied samples with the background value to evaluate the pollution degree of the heavy metal in the sediment (Burgess and Pellertier,

The continental shelf of the Arabian Sea is narrower towards the south and widened in the north along the west coast of India. The upwelling phenomena during the summer monsoon induce high biological productivity in the Arabian Sea along the southwest coast of India and resulting in the export of organic matter to the ocean floor (Habeebrehman et al., 2008). The maximum primary production was reported nearer to the coasts, with in 50 m depths and gradually decreases towards the open ocean (Nair et al., 1973). The changes in redox conditions caused by oxygen depletion, prevailing in the depositional environment also affects the mechanism of transport of metals from water column to sediments and vice versa. The coastal margins are seen to be potential sources of hazardous trace elements, as the effluents are discharged into waterbodies and finally flushed out to the open ocean. About 17104 m3/day of effluents reach the Sea from various small and large scale industries situated along the southwest coast (Udayakumar et al., 2014). The symptoms are there to show considerable impact of deterioration of estuarine waters on the coastal ecosystem (Jayakumar et al., 2001). Hence, determining the level of metals in the coastal margins could provide a better understanding of possible sources, ecological risk, and transport