Mercy Fariha Tahsin, Alam A K M Rashidul, Akbor Md Ahedul
Department of Environmental Science, Bangladesh University of Professionals, Mirpur, Dhaka 1216, Bangladesh.
Department of Environmental Sciences, Jahangirnagar University, Savar, Dhaka 1342, Bangladesh.
Heliyon. 2023 Mar 22;9(4):e14587. doi: 10.1016/j.heliyon.2023.e14587. eCollection 2023 Apr.
Microplastics (MPs) are prevalent in nature due to the proliferation of plastic in the environment. However, the presence of microplastics in lakes is largely unknown in comparison to other aquatic bodies. This study was performed to evaluate the abundance and characteristics of MPs in water, sediment, and fish from three major urban lakes in Dhaka, Bangladesh, namely Dhanmondi, Gulshan, and Hatir Jheel lake. The highest concentrations of microplastics in surface water (36 items/L), sediment (67 items/kg), fish (17 items/individual), and the gastrointestinal tract (4.88 items/gm) were observed. Highest abundance of microplastic in an individual fish was observed in from Dhanmondi Lake. The samples were visually examined using stereomicroscope and SEM, which revealed that films were the most prevalent kind of microplastics in both the water and the sediment samples, whereas pellets and foams predominated in the fish samples. Visual observation also revealed MPs dominated by <100 μm in size and transparent in color. According to the Fourier Transform Infrared (FTIR) analysis, the dominant polymers in the analyzed samples were high-density polyethylene, low-density polyethylene, ethylene vinyl acetate, polyvinyl chloride, polycarbonate, cellulose acetate, and polypropylene. MPs were relatively higher in the water and sediment samples of Gulshan Lake, and fish samples of Dhanmondi Lake. The results of this study indicate that microplastic contamination has occurred not only in the water and sediment but also in the inhabitant fishes of the lakes. However, it is discovered that the microplastic intake of fish was significantly related to body weight and length. The implication of the finding suggests that the presence of MPs in urban lakes has raised concerns about the potential human health impact.
由于环境中塑料的大量增加，微塑料（MPs）在自然界中普遍存在。然而，与其他水体相比，湖泊中微塑料的存在情况在很大程度上尚不明确。本研究旨在评估孟加拉国达卡市三个主要城市湖泊，即丹梦迪湖、古尔山和哈蒂尔杰尔湖的水体、沉积物和鱼类中微塑料的丰度及特征。研究观察到地表水中微塑料的最高浓度为36个/升，沉积物中为67个/千克，鱼类中为17个/个体，胃肠道中为4.88个/克。在丹梦迪湖的鱼中观察到单个鱼体内微塑料的丰度最高。使用体视显微镜和扫描电子显微镜对样本进行了目视检查，结果显示，薄膜是水体和沉积物样本中最常见的微塑料类型，而颗粒和泡沫在鱼类样本中占主导地位。目视观察还发现，微塑料的尺寸主要小于100微米，颜色为透明。根据傅里叶变换红外光谱（FTIR）分析，分析样本中的主要聚合物为高密度聚乙烯、低密度聚乙烯、乙烯-醋酸乙烯酯、聚氯乙烯、聚碳酸酯、醋酸纤维素和聚丙烯。古尔山湖水体和沉积物样本以及丹梦迪湖鱼类样本中的微塑料含量相对较高。本研究结果表明，微塑料污染不仅发生在水体和沉积物中，也存在于湖泊中的鱼类体内。然而研究发现，鱼类摄入微塑料的量与体重和体长显著相关。这一发现意味着城市湖泊中微塑料的存在引发了对其对人类健康潜在影响的担忧。
