Santhosh Athira Pulickal, Pyary Anisha, Biju Anagha, Partheeban Emmanuel Charles, Vethanayaham Jebashalomi, Rajendran Rajaram, Al-Sadoon Mohammad Khalid, Gulnaz Aneela
DNA Barcoding and Marine Genomics Laboratory, Department of Marine Science, Bharathidasan University, Tamil Nadu, Tiruchirappalli, India, 620 024.
Department of Zoology, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia.
Environ Sci Pollut Res Int. 2023 Feb;30(10):27980-27995. doi: 10.1007/s11356-022-24112-3. Epub 2022 Nov 17.
The spatiotemporal variations of five heavy metals (Cd, Cu, Cr, Pb, and Zn) in the beach sediments along the Tamil Nadu coast sourced from various anthropogenic activities were assessed using atomic absorption spectrophotometry (AAS). Various pollution monitoring indices were computed to clearly understand the metal pollution status along the Tamil Nadu coastline. The metal concentrations in sediments were typically higher in the summer season than in the monsoon season. In the monsoon season, metal concentration followed a decreasing order of Zn > Cr > Cu > Pb > Cd, and in the summer season, the order was Cr > Zn > Cu > Pb > Cd. During the monsoon season, freshwater runoff from the rainfall dilutes the sediments and their trace element load. However, due to a lack of freshwater influx during the summer season, the heavy metals in the sediments get concentrated and showed elevated levels. Geo-accumulation index, ecological risk index, pollution load index, and contamination degree clearly depict that Cd and Pb have higher accumulation and pose greater hazard when compared with other metals. The rivers flowing in the region also transport the heavy metals from the mainland to the estuaries and coastal environments. Metal levels along the Tamil Nadu coast are influenced by various anthropogenic activities persistent along the coastline. Some of the activities that cause metal contamination are mining, milling, electroplating, furnishing, pharmaceutical industries, fishing, harbor activities, urban runoff, and agricultural runoff, which release a variety of toxic metals into the coastal environment.
利用原子吸收分光光度法（AAS）评估了泰米尔纳德邦海岸海滩沉积物中源自各种人为活动的五种重金属（镉、铜、铬、铅和锌）的时空变化。计算了各种污染监测指标，以清楚了解泰米尔纳德邦海岸线沿线的金属污染状况。沉积物中的金属浓度通常在夏季高于季风季节。在季风季节，金属浓度的递减顺序为锌＞铬＞铜＞铅＞镉，而在夏季，顺序为铬＞锌＞铜＞铅＞镉。在季风季节，降雨产生的淡水径流会稀释沉积物及其微量元素负荷。然而，由于夏季缺乏淡水流入，沉积物中的重金属会浓缩并呈现出升高的水平。地累积指数、生态风险指数、污染负荷指数和污染程度清楚地表明，与其他金属相比，镉和铅具有更高的累积量且造成的危害更大。该地区的河流也将重金属从大陆输送到河口和沿海环境。泰米尔纳德邦海岸沿线的金属水平受到沿该海岸线持续存在的各种人为活动的影响。一些造成金属污染的活动包括采矿、研磨、电镀、家具制造、制药行业、捕鱼、港口活动、城市径流和农业径流，这些活动会将各种有毒金属释放到沿海环境中。
