Occurrence and migration of microplastics and plasticizers in different wastewater and sludge treatment units in municipal wastewater treatment plant

Abstract

● Reduce the quantifying MPs time by using Nile red staining.

● The removal rate of MPs and PAEs in wastewater and sludge were investigated.

● MPs and PAEs were firstly analyzed during thermal hydrolysis treatment.

● The removal of PAEs from wastewater and sludge was mainly biodegradation.

Microplastics (MPs) and plasticizers, such as phthalate esters (PAEs), were frequently detected in municipal wastewater treatment plants (MWTP). Previous research mainly studied the removal of MPs and PAEs in wastewater. However, the occurrence of MPs and PAEs in the sludge was generally ignored. To comprehensively investigate the occurrence and the migration behaviors of MPs and PAEs in MWTP, a series of representative parameters including the number, size, color, shape of MPs, and the concentrations of PAEs in wastewater and sludge were systematically investigated. In this study, the concentrations of MPs in the influent and effluent were 15.46±0.37 and 0.30±0.14 particles/L. The MP removal efficiency of 98.1% was achieved and about 73.8% of MPs were accumulated in the sludge in the MWTP. The numbers of MPs in the sludge before and after digestion were 4.40±0.14 and 0.31±0.01 particles/g (dry sludge), respectively. Fourier Transform Infrared Spectroscopy (ATR FT-IR) analysis showed that the main types of MPs were polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE), and polystyrene (PS). Six PAEs, including phthalate (DMP), diethyl phthalate (DEP), diisobutyl phthalate (DIBP), ortho dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), and bis(2-ethyl) hexyl phthalate (DEHP), were detected in the MWTP. The concentrations of total PAEs (ΣPAEs) in the influent and effluent were 76.66 and 6.28 µg/L, respectively. The concentrations of ΣPAEs in the sludge before and after digestion were 152.64 and 31.70 µg/g, respectively. In the process of thermal hydrolysis, the number and size of MPs decreased accompanied by the increase of the plasticizer concentration.

Graphical abstract

Keywords

Microplastics / Municipal wastewater treatment plant / Phthalate esters / Thermal hydrolysis

References

[1] AnbumaniS, KakkarP. (2018). Ecotoxicological effects of microplastics on biota: A review. Environmental Science and Pollution Research International, 25( 15): 14373– 14396

[2] AsefnejadA, KhorasaniM T, BehnamghaderA, FarsadzadehB, BonakdarS. (2011). Manufacturing of biodegradable polyurethane scaffolds based on polycaprolactone using a phase separation method: Physical properties and in vitro assay. International Journal of Nanomedicine, 6 : 2375– 2384

[3] AutaH S, EmenikeC U, FauziahS H. (2017). Distribution and importance of microplastics in the marine environment: A review of the sources, fate, effects, and potential solutions. Environment International, 102 : 165– 176

[4] CarrS A, LiuJ, TesoroA G. (2016). Transport and fate of microplastic particles in wastewater treatment plants. Water Research, 91 : 174– 182

[5] ChércolesAsensio R, SanAndrés Moya M, dela Roja J M, GómezM. (2009). Analytical characterization of polymers used in conservation and restoration by ATR-FTIR spectroscopy. Analytical and Bioanalytical Chemistry, 395( 7): 2081– 2096

[6] CheungP K, FokL. (2017). Characterisation of plastic microbeads in facial scrubs and their estimated emissions in China. Water Research, 122 : 53– 61

[7] ClaraM, WindhoferG, HartlW, BraunK, SimonM, GansO, ScheffknechtC, ChovanecA. (2010). Occurrence of phthalates in surface runoff, untreated and treated wastewater and fate during wastewater treatment. Chemosphere, 79( 9): 1078– 1084

[8] Eerkes-MedranoD, ThompsonR C, AldridgeD C. (2015). Microplastics in freshwater systems: A review of the emerging threats, identification of knowledge gaps and prioritisation of research needs. Water Research, 75 : 63– 82

[9] GaoD, LiZ, WangH, LiangH. (2018). An overview of phthalate acid ester pollution in China over the last decade: Environmental occurrence and human exposure. Science of the Total Environment, 645 : 1400– 1409

[10] GaoD, LiZ, WenZ, RenN. (2014). Occurrence and fate of phthalate esters in full-scale domestic wastewater treatment plants and their impact on receiving waters along the Songhua River in China. Chemosphere, 95 : 24– 32

[11] HartlineN L, BruceN J, KarbaS N, RuffE O, SonarS U, HoldenP A. (2016). Microfiber masses recovered from conventional machine washing of new or aged garments. Environmental Science & Technology, 50( 21): 11532– 11538

[12] HeB, GoonetillekeA, AyokoG A, RintoulL. (2020). Abundance, distribution patterns, and identification of microplastics in Brisbane River sediments, Australia. Science of the Total Environment, 700 : 134467

[13] HuertaLwanga E, GertsenH, GoorenH, PetersP, SalánkiT, vander Ploeg M, BesselingE, KoelmansA A, GeissenV. (2016). Microplastics in the terrestrial ecosystem: Implications for Lumbricus terrestris (Oligochaeta, Lumbricidae). Environmental Science & Technology, 50( 5): 2685– 2691

[14] JiangJ, WangX, RenH, CaoG, XieG, XingD, LiuB. (2020). Investigation and fate of microplastics in wastewater and sludge filter cake from a wastewater treatment plant in China. Science of the Total Environment, 746 : 141378

[15] JungM R, HorgenF D, OrskiS V, RodriguezC V, BeersK L, BalazsG H, JonesT T, WorkT M, BrignacK C, RoyerS J, HyrenbachK D, JensenB A, LynchJ M. (2018). Validation of ATR FT-IR to identify polymers of plastic marine debris, including those ingested by marine organisms. Marine Pollution Bulletin, 127 : 704– 716

[16] LaresM, NcibiM C, SillanpääM. (2018). Occurrence, identification and removal of microplastic particles and fibers in conventional activated sludge process and advanced MBR technology. Water Research, 133 : 236– 246

[17] LeeH, KimY. (2018). Treatment characteristics of microplastics at biological sewage treatment facilities in Korea. Marine Pollution Bulletin, 137 : 1– 8

[18] LiJ, LiuH, Paul ChenJ. (2018a). Microplastics in freshwater systems: A review on occurrence, environmental effects, and methods for microplastics detection. Water Research, 137 : 362– 374

[19] LiX, ChenL, MeiQ, DongB, DaiX, DingG, ZengE Y. (2018b). Microplastics in sewage sludge from the wastewater treatment plants in China. Water Research, 142 : 75– 85

[20] LiY, YaoJ, NieP, FengX, LiuJ. (2021). An effective method for the rapid detection of microplastics in soil. Chemosphere, 276 : 128696

[21] LongZ, PanZ, WangW, RenJ, YuX, LinL, LinH, ChenH, JinX. (2019). Microplastic abundance, characteristics, and removal in wastewater treatment plants in a coastal city of China. Water Research, 155 : 255– 265

[22] LoraineG A, PettigroveM E. (2006). Seasonal variations in concentrations of pharmaceuticals and personal care products in drinking water and reclaimed wastewater in southern California. Environmental Science & Technology, 40( 3): 687– 695

[23] MaB, XueW, HuC, LiuH, QuJ, LiL. (2019). Characteristics of microplastic removal via coagulation and ultrafiltration during drinking water treatment. Chemical Engineering Journal, 359 : 159– 167

[24] MagniS, BinelliA, PitturaL, AvioC G, Della TorreC, ParentiC C, GorbiS, RegoliF. (2019). The fate of microplastics in an Italian wastewater treatment plant. Science of the Total Environment, 652 : 602– 610

[25] MasonS A, GarneauD, SuttonR, ChuY, EhmannK, BarnesJ, FinkP, PapazissimosD, RogersD L. (2016). Microplastic pollution is widely detected in US municipal wastewater treatment plant effluent. Environmental Pollution, 218 : 1045– 1054

[26] MurphyF, EwinsC, CarbonnierF, QuinnB. (2016). Wastewater treatment works (WwTW) as a source of microplastics in the aquatic environment. Environmental Science & Technology, 50( 11): 5800– 5808

[27] NelH A, ChetwyndA J, KelleherL, LynchI, MansfieldI, MargenatH, OnojaS, Goldberg OppenheimerP, Sambrook SmithG H, KrauseS. (2021). Detection limits are central to improve reporting standards when using Nile red for microplastic quantification. Chemosphere, 263 : 127953

[28] SetäläO, MagnussonK, LehtiniemiM, NorénF. (2016). Distribution and abundance of surface water microlitter in the Baltic Sea: A comparison of two sampling methods. Marine Pollution Bulletin, 110( 1): 177– 183

[29] ShrutiV C Pérez-GuevaraF RoyP D Kutralam-MuniasamyG ( 2022). Analyzing microplastics with Nile Red: Emerging trends, challenges, and prospects. Journal of Hazardous Materials, 423(Pt B): 127171

[30] SuY, ZhangK, ZhouZ, WangJ, YangX, TangJ, LiH, LinS. (2020). Microplastic exposure represses the growth of endosymbiotic dinoflagellate Cladocopium goreaui in culture through affecting its apoptosis and metabolism. Chemosphere, 244 : 125485

[31] TakdastanA, NiariM H, BabaeiA, DobaradaranS, JorfiS, AhmadiM. (2021). Occurrence and distribution of microplastic particles and the concentration of Di 2-ethyl hexyl phthalate (DEHP) in microplastics and wastewater in the wastewater treatment plant. Journal of Environmental Management, 280 : 111851

[32] UstabasiG S, BaysalA. (2019). Occurrence and risk assessment of microplastics from various toothpastes. Environmental Monitoring and Assessment, 191( 7): 438– 446

[33] WangR, JiM, ZhaiH, LiuY. (2020). Occurrence of phthalate esters and microplastics in urban secondary effluents, receiving water bodies and reclaimed water treatment processes. Science of the Total Environment, 737 : 140219

[34] WrightS L KellyF J ( 2017). Plastic and human health: A micro issue? Environmental Science & Technology, 51( 12): 6634− 6647

[35] YuJ, WangP, NiF, CizdzielJ, WuD, ZhaoQ, ZhouY. (2019). Characterization of microplastics in environment by thermal gravimetric analysis coupled with Fourier transform infrared spectroscopy. Marine Pollution Bulletin, 145 : 153– 160

[36] ZhangK, XiongX, HuH, WuC, BiY, WuY, ZhouB, LamP K S, LiuJ. (2017). Occurrence and characteristics of microplastic pollution in Xiangxi Bay of three gorges reservoir, China. Environmental Science & Technology, 51( 7): 3794– 3801

[37] ZhangL, LiuJ, XieY, ZhongS, GaoP. (2021a). Occurrence and removal of microplastics from wastewater treatment plants in a typical tourist city in China. Journal of Cleaner Production, 291 : 125968

[38] ZhangY, JiaoY, LiZ, TaoY, YangY. (2021b). Hazards of phthalates (PAEs) exposure: A review of aquatic animal toxicology studies. Science of the Total Environment, 771 : 145418

[39] ZiajahromiS, NealeP A, RintoulL, LeuschF D L. (2017). Wastewater treatment plants as a pathway for microplastics: Development of a new approach to sample wastewater-based microplastics. Water Research, 112 : 93– 99

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