The present study investigated heavy metals (Mn, Cr, Cu, Ni, Pb, and Zn) distribution in the surface sediments off Karaikal – Velankanni offshore along the east coast of Bay of Bengal as an indicator of marine pollution during 2004-2005. The sediments were analyzed for sand, silt, clay ratio, CaCO₃, organic matter, and heavy metal (Mn, Cr, Cu, Ni, Pb, and Zn) contents. The contamination factor (CF) values for the heavy metals are found to be in the order: Mn >Cr >Ni >Zn >Cu >Pb during August 2004; and during January 2005 the CF values were found to be in the order: Zn >Mn >Cu >Ni >Pb >Cr. Zn contamination was found to be low to moderate. 10 samples were found with low and moderate Mn contamination. All the samples displayed moderate contamination with Cu, Ni, and Pb. Among the selected sediments, those which are collected from Karaikal and Velankanni shore were found to be highly contaminated by heavy elements due to the discharge of effluents from petrochemical, oil spills, port activity, and shipping activities. The occurrence of a wide range of elements in coastal sediments is mainly related to the textural variability of sediments during 2004 and 2005.

中文翻译：

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印度东南沿海海域表层沉积物中的重金属特征：对海洋污染的影响

本研究调查了孟加拉湾东海岸沿岸Karaikal – Velankanni近海的表层沉积物中重金属（Mn，Cr，Cu，Ni，Pb和Zn）的分布，作为2004-2005年海洋污染的指标。分析沉积物的沙子，淤泥，粘土比，CaCO ₃，有机物和重金属（Mn，Cr，Cu，Ni，Pb和Zn）的含量。发现重金属的污染因子（CF）值的顺序为：2004年8月Mn> Cr> Ni> Zn> Cu> Pb；在2005年1月，CF值的顺序为：锌>锰>铜>镍>铅>铬。发现锌污染程度低至中等。发现10个样品的锰污染程度中等。所有样品均显示出中等程度的铜，镍和铅污染。在选定的沉积物中，由于石化，废水泄漏，港口活动和航运活动中的废水排放，从Karaikal和Velankanni海岸收集的沉积物被重元素高度污染。