摘要
     最近，废水处理过程中聚氯乙烯（PVC）微塑料在污水污泥中的滞留引起了人们的关注。然而，PVC微塑料对废活性污泥（WAS）的厌氧消化产生甲烷的影响从未被记录。在这项工作中，研究了PVC微塑料（1毫米，10-60颗粒/克TS）对WAS厌氧甲烷产生的影响。 10个颗粒/ g TS的PVC微塑料的存在显着（P = 0.041）使甲烷产量增加5.9±0.1％，但更高水平的PVC微塑料（即20,40和60个颗粒/ g TS）抑制甲烷产量至90.6对照的±0.3％，80.5±0.1％和75.8±0.2％。基于模型的分析表明，> 20颗粒/ g TS的PVC微塑料降低了WAS的甲烷电位（B0）和水解系数（k）。机理研究表明，PVC微塑料中的双酚-A（BPA）浸出是甲烷产生减少的主要原因，对水解 - 酸化过程产生显着的（P = 0.037,0.01,0.004）抑制作用。 PVC微塑料的长期影响表明，微生物群落正朝着水解 - 酸化和甲烷化的方向转变。总之，PVC微塑料通过浸出有毒的BPA对WAS厌氧消化产生负面影响。

Abstract

The retention of polyvinylchloride (PVC) microplastics in sewage sludge during wastewater treatment raises concerns recently. However, the effects of PVC microplastics on methane production from anaerobic digestion of waste activated sludge (WAS) have never been documented. In this work, the effects of PVC microplastics (1 mm, 10-60 particles/g TS) on anaerobic methane production from WAS were investigated. The presence of 10 particles/g TS of PVC microplastics significantly (P = 0.041) increased methane production by 5.9 ± 0.1%, but higher levels of PVC microplastics (i.e., 20, 40 and 60 particles/g TS) inhibited methane production to 90.6 ± 0.3%, 80.5 ± 0.1% and 75.8 ± 0.2% of the control, respectively. Model-based analysis indicated that PVC microplastics at > 20 particles/g TS decreased both methane potential (B0) and hydrolysis coefficient (k) of WAS. The mechanistic studies showed that bisphenol-A (BPA) leaching from PVC microplastics was the primary reason for the decreased methane production, causing significant (P = 0.037, 0.01, 0.004) inhibitory effects on the hydrolysis-acidification process. The long-term effects of PVC microplastics revealed that the microbial community was shifted in the direction against hydrolysis-acidification and methanation. In conclusion, PVC microplastic caused negative effects on WAS anaerobic digestion through leaching the toxic BPA.

https://www.ncbi.nlm.nih.gov/pubmed/30758964