摘要

污水处理厂（WwTW）排放的城市污水被怀疑是微塑料（MP）对环境的重要贡献者，因为许多个人护理产品都含有塑料微珠。在处理过程的不同阶段对微塑料采样二级WwTW（人口当量为650000），以确定在治疗过程的哪个阶段MP被移除。进水平均含有15.70（±5.23）MP·L-1。在最终出水中，这降低到0.25（±0.04）MP·L-1，降低了98.41％。尽管如此大幅减少，我们仍计算出这个WwTW每天将6500万微塑料释放到接收水中。在除脂阶段（19.67（±4.51）MP / 2.5g）中积聚并且被除去的微弹性的很大一部分，仅在润滑脂中发现了广泛公开的微珠。这项研究表明，尽管现代处理厂在处理如此大量的污水时能达到有效的MP去除率，即使每升污水释放的适量微塑料也可能导致大量微塑料进入环境。这是第一个详细描述废水处理过程中微塑料的去向的研究。

Municipal effluent discharged from wastewater treatment works (WwTW) is suspected to be a significant contributor of microplastics (MP) to the environment as many personal care products contain plastic microbeads. A secondary WwTW (population equivalent 650 000) was sampled for microplastics at different stages of the treatment process to ascertain at what stage in the treatment process the MP are being removed. The influent contained on average 15.70 (±5.23) MP·L–1. This was reduced to 0.25 (±0.04) MP·L–1 in the final effluent, a decrease of 98.41%. Despite this large reduction we calculate that this WwTW is releasing 65 million microplastics into the receiving water every day. A significant proportion of the microplastic accumulated in and was removed during the grease removal stage (19.67 (±4.51) MP/2.5 g), it was only in the grease that the much publicised microbeads were found. This study shows that despite the efficient removal rates of MP achieved by this modern treatment plant when dealing with such a large volume of effluent even a modest amount of microplastics being released per liter of effluent could result in significant amounts of microplastics entering the environment. This is the first study to describe in detail the fate of microplastics during the wastewater treatment process.

https://pubs.acs.org/doi/abs/10.1021/acs.est.5b05416