Microplastics pollution in aquatic ecosystems is of great concern; however, systemic investigations are still lacking in freshwater wetland systems used for wastewater treatment. The present study discusses such freshwater wetland system in Eastern India to understand its microplastics transport mechanism, heavy metals association and microplastics removal efficiency. Microplastics (63 µm - 5 mm) were heavily found in surface water and sediments of treatment ponds (7.87 to 20.39 items/L and 2124.84 to 6886.76 items/kg) and associated wastewater canals (30.46 to 137.72 items/L and 1108.78 to 34612.87 items/kg). A high content of toxic metals (As, Cd, Cr, Cu, Ni, Pb and Zn) were found on the microplastics with polyethylene terephthalate and polyethylene as major plastics types which were also found in fishes and macroinvertebrates of treatment ponds. Machine learning algorithm revealed a close association between microplastics content in fishes and surface water, indicating risk associated with floating microplastics to the aquatic biota. The study also revealed that microplastics were acting as heavy metals vector and potentially causing fish contamination. Surface water microplastics removing efficiency of the treatment ponds was estimated to be 53%. The study bespeaks about transport of microplastics through wastewater canals and their retention in treatment ponds emphasizing sustainability maintenance of natural wastewater treatment systems especially considering microplastics contamination to the aquatic biota of freshwater wetland systems.

水生生态系统中的微塑料污染非常令人关注。然而，用于废水处理的淡水湿地系统仍然缺乏系统的研究。本研究讨论了印度东部这样的淡水湿地系统，以了解其微塑料的运输机制，重金属缔合和微塑料的去除效率。在处理池的地表水和沉积物中大量发现了微塑料（63 µm-5 mm）（7.87至20.39物品/ L和2124.84至6886.76物品/ kg）和相关的污水渠（30.46至137.72物品/ L和1108.78至34612.87物品/公斤）。在微塑料中发现了高含量的有毒金属（As，Cd，Cr，Cu，Ni，Pb和Zn），其中聚对苯二甲酸乙二酯和聚乙烯是主要的塑料类型，在处理池塘的鱼类和大型无脊椎动物中也有发现。机器学习算法揭示了鱼类中的微塑料含量与地表水之间的紧密联系，表明与微塑料漂浮到水生生物区系相关的风险。研究还表明，微塑料是重金属的载体，并可能导致鱼类污染。估计处理池的地表水微塑料去除效率为53％。这项研究表明，微塑料通过废水渠的运输及其在污水处理池中的滞留，强调了天然废水处理系统的可持续性维护，特别是考虑到微塑料对淡水湿地系统水生生物的污染。表明与微塑料漂浮到水生生物群有关的风险。研究还表明，微塑料是重金属的载体，并可能导致鱼类污染。估计处理池的地表水微塑料去除效率为53％。这项研究表明，微塑料通过废水渠的运输及其在污水处理池中的滞留，强调了天然废水处理系统的可持续性维护，特别是考虑到微塑料对淡水湿地系统水生生物的污染。表明与微塑料漂浮到水生生物群有关的风险。研究还表明，微塑料是重金属的载体，并可能导致鱼类污染。估计处理池的地表水微塑料去除效率为53％。这项研究表明，微塑料通过废水渠的运输及其在污水处理池中的滞留，强调了天然废水处理系统的可持续性维护，特别是考虑到微塑料对淡水湿地系统水生生物的污染。