Unveiling the protective role of biofilm formation on the photoaging of microplastics  

作　　者：ZHANG HaiYu LIU Peng ZHANG JiaYu DAI JiaMin ZHANG XinRui ZHANG ZiXuan JIA HanZhong 

机构地区：[1]Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China,Ministry of Agriculture,College of Natural Resources and Environment,Northwest A&F University,Yangling 712100,China [2]Key Laboratory of Organic Compound Pollution Control Engineering,School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200444,China

出　　处：《Science China(Technological Sciences)》2024年第10期3067-3078,共12页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42107434 and 42077351);the Postdoctoral Science Foundation of China(Grant Nos.2020M680160 and 2022T150536).

摘　　要：In natural water,microplastics(MPs)inevitably undergo microbial colonization to form biofilm,while the effect of biofilm formation on the photoaging of MPs remains unknown.This study systematically investigated the photoaging behavior of disposable box-derived polypropylene(PPMPs)and polystyrene(PSMPs)mediated by formed biofilm in water.After incubating in Weihe water samples for 105 d,the biofilm was validated to form in PPMPs and PSMPs,with higher formation in PSMPs.In particular,biofilm formation inhibited the photoaging of PPMPs and PSMPs,with an 11.1%and 50.6%decrease in photooxidation compared to their virgin counterparts after 20 d of ultraviolet(UV)irradiation.Moreover,the photoaging route of MPs such as the reaction priority of functional groups(e.g.,C–H,C=O,and benzene ring)was altered,indicating the important role of biofilm formation in the photoaging process of MPs.The protective effect of the biofilm was mainly caused by the role of optical light filters that absorbed UV energy by sacrificing themselves.Also,as the main attacker on MPs,the production of reactive oxygen species(ROS,mainly^(1)O_(2)and·OH)was inhibited by biofilm,which was mainly responsible for the decreased photoaging of MPs.This study revealed the important role of biofilm in the photoaging process of MPs and suggested a higher resistance of(micro)plastics in natural water than that in the laboratory using pure MPs,which contributed to a deeper understanding of the environmental fate and pollution of MPs.

关 键 词：microplastics BIOFILM PHOTOAGING physical shielding reactive oxygen species 

分 类 号：X52[环境科学与工程—环境工程] X505