Aquatic Environmental Biotechnology & Nanotechnology Division, ICAR-Central Inland Fisheries Research Institute (CIFRI), Barrackpore, West Bengal, 700120, India.
ICAR- Central Inland Fisheries Research Institute (CIFRI), Barrackpore, West Bengal, 700120, India.
Environ Sci Pollut Res Int. 2022 Sep;29(45):67801-67820. doi: 10.1007/s11356-022-20573-8. Epub 2022 May 7.
East Kolkata Wetland (EKW) is one of the largest sewage-fed wetlands in the world, which support the livelihood of thousands of peoples. However, at present, EKW system has become ecologically vulnerable due to the discharge of toxic waste through the sewage canal from the Kolkata metropolitan city. Hence, it becomes very important to understand the inflow and load of potentially toxic elements (PTE) in the sediment, water, and fish of sewage-fed wetland used for aquaculture activities. In this study, one of the polluted wetland from EKW, Sardar bherry, was selected as the study area. Sediment samples (45) were collected from 15 sites to characterize the PTEs concentrations levels utilizing inductively coupled plasma mass spectrometry, and their spatial distribution pattern and pollution quality indices were estimated. Water (45) and fish (7) samples were also analyzed to understand the distribution pattern of PTEs from sediment to water and water to fish. The geostatistical prediction map showed that the concentration range of Cr, Fe, Cu, Co, Zn, Cd, Ni, Pb, and Mn in sampling stations were 27.3-84.1 μg g, 7281-30193 μg g, 50.6-229.7 μg g, 4.8-15.3 μg g, 113.4-776.9 μg g, 10.0-26.9 μg g, 23.8-55.7 μg g, 9.5-39.3 μg g, and 188.6-448.5 μg g respectively. Pollution is alarming in sediment as all of the studied PTEs exceed the threshold effect level according to Sediment Quality Guidelines. Cd levels in sediments were found to be upper than the lowest effect level (LEL), probable effect level (PEL), threshold effect level (TEL), and severe effect level (SEL) for all sample locations. Several pollution assessment indexes (contamination factor, geo-accumulation index, ecological risk index, etc.) also showed that sediment samples were severely polluted by Cd. PTEs status in water and fish is within permissible limits. The study emphasizes that attention should be paid to controlling the excessive accumulation of PTEs in sediment that would further harm the ecological environment and ultimately human health.
东科塔卡湿地（EKW）是世界上最大的污水湿地之一，为数千人的生计提供了支持。然而，目前由于从加尔各答大都市通过污水渠排放有毒废物，EKW 系统的生态已经变得脆弱。因此，了解用于水产养殖活动的污水湿地中的潜在有毒元素（PTE）在沉积物、水和鱼类中的流入量和负荷量变得非常重要。在这项研究中，选择了来自 EKW 的一个受污染湿地，即萨尔达尔贝里，作为研究区域。从 15 个地点采集了 45 个沉积物样本，利用电感耦合等离子体质谱法对其进行了特征描述，评估了其空间分布模式和污染质量指数。还分析了水（45 个样本）和鱼类（7 个样本）样本，以了解 PTE 从沉积物到水以及水到鱼的分布模式。地统计预测图显示，采样点 Cr、Fe、Cu、Co、Zn、Cd、Ni、Pb 和 Mn 的浓度范围分别为 27.3-84.1μg/g、7281-30193μg/g、50.6-229.7μg/g、4.8-15.3μg/g、113.4-776.9μg/g、10.0-26.9μg/g、23.8-55.7μg/g、9.5-39.3μg/g 和 188.6-448.5μg/g。根据沉积物质量指南，所有研究的 PTE 都超过了阈值效应水平，因此沉积物中的污染情况令人震惊。在所有采样点，沉积物中的 Cd 含量都高于最低效应水平（LEL）、可能效应水平（PEL）、阈值效应水平（TEL）和严重效应水平（SEL）。几种污染评估指数（污染因子、地积累指数、生态风险指数等）也表明，Cd 严重污染了沉积物样品。水和鱼类中的 PTE 含量在允许范围内。研究强调，应注意控制 PTE 在沉积物中的过度积累，这将进一步危害生态环境，最终危害人类健康。
