Illinois Sustainable Technology Center, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA.
Illinois Sustainable Technology Center, Prairie Research Institute, University of Illinois at Urbana-Champaign, Champaign, IL 61820, USA.
Sci Total Environ. 2024 Dec 1;954:176751. doi: 10.1016/j.scitotenv.2024.176751. Epub 2024 Oct 6.
Landfills and wastewater treatment plants (WWTP) are point sources for many emerging contaminants, including microplastics and per- and polyfluoroalkyl substances (PFAS). Previous studies have estimated the abundance and transport of microplastics and PFAS separately in landfills and WWTPs. In addition, previous studies typically report concentrations of microplastics as particle count/L or count/g sediment, which do not provide the information needed to calculate mass balances. We measured microplastics and PFAS in four landfill-WWTP systems in Illinois, USA, and quantified mass of both contaminants in landfill leachate, WWTP influent, effluent, and biosolids. Microplastic concentrations in WWTP influent were similar in magnitude to landfill leachates, in the order of 10 μg plastic/L (parts-per-billion). In contrast, PFAS concentrations were higher in leachates (parts-per-billion range) than WWTP influent (parts-per-trillion range). After treatment, both contaminants had lower concentrations in WWTP effluent, although were abundant in biosolids. We concluded that WWTPs reduce PFAS and microplastics, lowering concentrations in the effluent that is discharged to nearby surface waters. However, partitioning of both contaminants to biosolids may reintroduce them as pollutants when biosolids are landfilled or used as fertilizer.
垃圾填埋场和废水处理厂（WWTP）是许多新兴污染物的点源，包括微塑料和全氟烷基物质（PFAS）。先前的研究分别估计了微塑料和 PFAS 在垃圾填埋场和 WWTP 中的丰度和迁移。此外，先前的研究通常报告微塑料的浓度为颗粒计数/L 或计数/g 沉积物，这不能提供计算质量平衡所需的信息。我们在美国伊利诺伊州的四个垃圾填埋场-WWTP 系统中测量了微塑料和 PFAS，并量化了垃圾填埋场渗滤液、WWTP 进水、出水和生物固体中这两种污染物的质量。WWTP 进水的微塑料浓度与垃圾填埋场渗滤液相当，为 10μg 塑料/L（十亿分之一）。相比之下，PFAS 的浓度在渗滤液中较高（十亿分之一范围），而在 WWTP 进水（万亿分之一范围）中较低。经过处理后，两种污染物在 WWTP 出水中的浓度较低，尽管在生物固体中含量丰富。我们得出结论，WWTP 减少了 PFAS 和微塑料，降低了排放到附近地表水的废水中的浓度。然而，当生物固体被填埋或用作肥料时，这两种污染物向生物固体的分配可能会重新将它们作为污染物引入。
