Kara Murdoch Fadime, Sun Yanchen, Fuller Mark E, Mullins Larry, Hill Amy, Lilly Jacob, Wilson John, Löffler Frank E, Kucharzyk Katarzyna H
Battelle Memorial Institute, 505 King Ave, Columbus, OH 43201, USA.
Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, USA.
Toxics. 2025 Jul 31;13(8):656. doi: 10.3390/toxics13080656.
Microplastics (MPs) and nanoplastics (NPs) can affect microbial abundance and activity, likely by damaging cell membrane components. While their effects on anaerobic digestion are known, less is understood about their impact on microbes involved in contaminant bioremediation. Chlorinated volatile organic contaminants (CVOCs) such as tetrachloroethene (PCE) and explosives like hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) are common in the environment, and their bioremediation is a promising cleanup strategy. This study examined how polystyrene (PS) and polyamide 6 (PA6) MPs and NPs influence CVOC and RDX biodegradation. PS particles did not inhibit the CVOC-degrading community SDC-9, but PA6 MPs impaired the reductive dechlorination of trichloroethene (TCE) to cis-1,2-dichloroethene (-DCE), causing a "-DCE stall" with no further conversion to vinyl chloride (VC) or ethene. Only 45% of TCE was dechlorinated to -DCE, and abundance dropped 1000-fold in 35 days with PA6 MPs. In contrast, neither PA6 nor PS MPs and NPs affected RDX biotransformation. These results highlight the significant impact of PA6 MPs on CVOC biodegradation and the need to consider plastic pollution in environmental management.
微塑料（MPs）和纳米塑料（NPs）可能通过破坏细胞膜成分来影响微生物的丰度和活性。虽然它们对厌氧消化的影响是已知的，但对于它们对参与污染物生物修复的微生物的影响了解较少。环境中常见的氯代挥发性有机污染物（CVOCs），如四氯乙烯（PCE）和六氢-1,3,5-三硝基-1,3,5-三嗪（RDX）等炸药，其生物修复是一种很有前景的清理策略。本研究考察了聚苯乙烯（PS）和聚酰胺6（PA6）微塑料和纳米塑料如何影响CVOC和RDX的生物降解。PS颗粒不会抑制CVOC降解菌群SDC-9，但PA6微塑料会损害三氯乙烯（TCE）向顺式-1,2-二氯乙烯（-DCE）的还原脱氯，导致出现“-DCE停滞”，无法进一步转化为氯乙烯（VC）或乙烯。只有45%的TCE被脱氯为-DCE，在PA6微塑料存在的情况下，35天内其丰度下降了1000倍。相比之下，PA6和PS微塑料及纳米塑料均不影响RDX的生物转化。这些结果凸显了PA6微塑料对CVOC生物降解的显著影响，以及在环境管理中考虑塑料污染的必要性。
