Understanding Biogeochemical Cycling of Trace Elements and Heavy Metals in Estuarine Ecosystems

Nature has slow occurring biogeochemical cycles of trace elements and heavy metals and the cycles have significantly controlled environmental fates of these elements. The trace elements and heavy metals cannot be degraded like organic pollutants and they may transform and become stable and persistent contaminants that accumulate in soil and sediments [1–3]. Estuaries play an important role in human civilization such as trading among populations. Many industries are able to take advantage of the estuary for industrial effluents as a source of cold water for heated discharge. As a result, estuaries and coastal marine ecosystems receive a variety of pollutants and contaminants that potentially have adverse effects not only on biota living in these habitats, but also on the humans who consume them [4]. Anthropogenic activities such as pollution, industrial, offshore oil and gas exploration have increased the levels of trace element and metal ions in natural water system. Improper disposal of contaminants from hazardous waste sites and industrial facilities have contributed to the estuary contamination as well. All these toxic elements have been accumulated in soils and sediments and can be ingested or stored in and enter into marina biota (fish and seafood) that is then consumed by humans.