ASSESSMENT OF MARINE POLLUTION IN INVERTEBRATES FROM THE COX’S BAZAR COAST,BAY OF BENGAL

The ecology of the Bay of Bengal is diverse and supports a wide range of marine life and ecosystem. At present the tiny micro-sized plastic particles have been spread over from a densely urbanized city to the deeper part of the ocean floor. The study is concentrated on the microplastic consumption of twelve invertebrate species collected from the coastal zone of the Cox’s Bazar district. To investigate the existence of microplastics, the gastrointestinal tract of these samples was separated, desiccated, and softly disintegrated into powders to analyze through the microscope and FT-IR spectroscopy. Four types of microplastics (fibres 81%, fragments 14%, films 4% and foams 1%) are recognized among a total of 132 particles after visualizing dried powdered species samples under a stereomicroscope. Through FT-IR data analysis, polyethene, polypropylene, polyurethane and polyamides types of polymers are identified suggesting multiple sources of plastic waste. The X-ray fluorescence (XRF) technique was used to analyze the heavy metal concentrations in the samples. From this study it appeared that invertebrates are more contaminated by heavy metals concentration than sediments identified by three statistical analyses. Mercury (Hg) and Lead (Pb) was found at a level greater than maximum allowable concentration levels in the invertebrates. Other heavy metals like Cr, Mn, Fe, Sr, Co, Cu and Zn were also found in both sediment and invertebrate samples. Samples were then evaluated using reliable pollution index methods. Contamination Factor (CF), Degree of Contamination (Cd), and Pollution Load Index (PLI) methods have shown low to moderate levels of contamination in invertebrates and sediments. Invertebrate samples were found to be more contaminated than the sediment samples. Due to the concentration levels in the invertebrates, the marine ecology of Cox’s

Bazar coast is facing a great risk and people who consume seafood are vulnerable to major health effects.