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Yang X, Niu S, Li M, Niu Y, Shen K, Dong B, Hur J, Li X. Leaching behavior of microplastics during sludge mechanical dewatering and its effect on activated sludge. WATER RESEARCH 2024; 266:122395. [PMID: 39255567 DOI: 10.1016/j.watres.2024.122395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2024] [Revised: 08/16/2024] [Accepted: 09/03/2024] [Indexed: 09/12/2024]
Abstract
Dewatering is an indispensable link in sludge treatment, but its effect on the microplastics (MPs) remains inadequately understood. This study investigated the physicochemical changes and leaching behavior of MPs during the mechanical dewatering of sludge, as well as the impact of MP leachates on activated sludge (AS). After sludge dewatering, MPs exhibit rougher surfaces, decreased sizes and altered functional groups due to the addition of dewatering agents and the application of mechanical force. Meanwhile, plastic additives, depolymerization products, and derivatives of their interactions are leached from MPs during sludge dewatering process. The concentration of MP-based leachates in sludge is 2-25 times higher than that in water. The enhancement of pH and ionic strength caused by dewatering agents induces the release of MP leachates enriched with protein-like, fulvic acid-like, and soluble microbial by-product-like substances. The reflux of MP leachates in sludge dewatering liquor to the wastewater treatment system negatively impacts AS, leading to a decrease in COD removal rate and inhibition of the extracellular polymeric substances secretion. More importantly, MP leachates cause oxidative stress to microbial cells and alter the microbial community structure of AS at the phylum and genus levels. These findings confirm that MPs undergo aging and leaching during sludge dewatering process, and MP leachates may negatively affect the wastewater treatment system.
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Affiliation(s)
- Xingfeng Yang
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Shiyu Niu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Man Li
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Yulong Niu
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Kailiang Shen
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China
| | - Bin Dong
- State Key Laboratory of Pollution Control and Resources Reuse, National Engineering Research Center for Urban Pollution Control, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China.
| | - Jin Hur
- Department of Environment and Energy, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, South Korea
| | - Xiaowei Li
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, PR China.
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Chen Z, Ren J, Yun Z, Wen Q, Fu Q, Qiu S. Effects of agricultural mulch film on swine manure composting: Film degradation and nitrogen transformation. BIORESOURCE TECHNOLOGY 2024; 406:131042. [PMID: 38936678 DOI: 10.1016/j.biortech.2024.131042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/23/2024] [Accepted: 06/24/2024] [Indexed: 06/29/2024]
Abstract
The utilization of biodegradable mulch films (bio-MFs) is essential for agricultural safety. This study explored the effects of no MF (CK), aging bio-MF (BM), non-aging bio-MF (NBM), and aging polyethylene (PE)-MF (PEM) on swine manure composting. The results demonstrated that outdoor aging (45 days) accelerated the macroscopic degradation of bio-MF in the BM. A reduction in NH4+-N and NH3 emissions in the initial composting was observed owing to an increase in the carbon source or the bulking effect provided by the MFs. N2O emissions from days 9 to 21 were higher in the PEM than other treatments because of the formation of anaerobic zone in the MF-based aggregates. An obvious increase of amoA in PEM indicated a promoted nitrification during the maturation phase, meanwhile the increase of NO2--N and aggregate promoted denitrification. Altogether, MF influenced composting through the synergistic effects of increasing the carbon source, bulking effect, and aggregates.
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Affiliation(s)
- Zhiqiang Chen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, Heilongjiang 150090, China; School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Jie Ren
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, Heilongjiang 150090, China; School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Zerui Yun
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, Heilongjiang 150090, China; School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Qinxue Wen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, Heilongjiang 150090, China; School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China.
| | - Qiqi Fu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, Heilongjiang 150090, China; School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
| | - Shan Qiu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin, Heilongjiang 150090, China; School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150090, China
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Tong Y, Xie M, Xv H, Sun R, Wang Q, Li J. Microplastics and Endocrine Disruptors in Typical Wastewater Treatment Plants in Megacity Shanghai. TOXICS 2024; 12:345. [PMID: 38787124 PMCID: PMC11126012 DOI: 10.3390/toxics12050345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2024] [Revised: 04/30/2024] [Accepted: 05/06/2024] [Indexed: 05/25/2024]
Abstract
The fast development of China's urbanization has led to a notable release of emerging pollutants, including microplastics (MPs) and endocrine disruptors (EDCs). Generally, these pollutants enter the coastal environment through the discharge of wastewater treatment plants (WWTPs) and finally threaten the organisms in the receiving waterbody. The study investigated the environmental behavior of MPs and EDCs in two typical WWTPs in one of the megacities in China, Shanghai. The abundance of MPs in the influent ranged from 321 to 976 items/L. Four shapes (films, fragments, fibers, and microbead) were found, while fibers and films dominated. Transparent (31-63%) and white (20-47%) MPs were more frequently observed, while polyethylene terephthalate, cellulose, and cellophane were the main polymetric materials. The size of the MPs fell between 15.8 μm and 2220 μm, and the smaller one (<500 μm) dominated. The removal efficiencies of the two WWTPs for MPs ranged from 64% to 92%, and both WWTPs performed better for large pieces of MPs (>500 μm). For EDCs, total concentrations in the influent were detected, ranging from 113 to 2780 ng/L. Two groups, including phenolic estrogens (PEs) and steroid estrogens (SEs), were detected, and PEs, especially bisphenol A (BPA), were the predominant individuals among the studied EDCs. Specifically, PEs ranged from 82.8 to 2637 ng/L, while SEs ranged from 27.3 to 143 ng/L. The removal efficiencies of the WWTPs for EDCs varied (82.8-100%) as well, possibly due to the different treatment compartments and contamination load in the influent. Seasonal variations for both MPs and EDCs were observed. Specifically, concentrations of MPs and EDCs in WWTPs influent were higher in the wet season, as well as the removal efficiency. Furthermore, there was a correlation observed between the concentrations of MPs and EDCs, suggesting that MPs and EDCs may originate from the same source and that EDCs released by MPs cannot be ignored during treatment. Finally, the study evaluated the environmental risk of the effluents. MPs led to a minor risk (Level I), while EDCs might lead to an adverse impact on algae (RQs = 0.0014-0.024) and fish (RQs = 3.4-30.2). In summary, WWTPs received considerable amounts of MPs and EDCs. Although the WWTPs removed the contaminants efficiently, the environmental risk of the effluent needs to be noted.
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Affiliation(s)
- Yuxiao Tong
- College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai 201306, China; (Y.T.); (H.X.); (J.L.)
| | - Manjun Xie
- Shanghai Haibin Sewage Treatment Plant, Pudong, Shanghai 201306, China;
| | - Hanwen Xv
- College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai 201306, China; (Y.T.); (H.X.); (J.L.)
| | - Ruihua Sun
- Pudong Environmental Monitoring Station, Pudong, Shanghai 201306, China;
| | - Qian Wang
- College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai 201306, China; (Y.T.); (H.X.); (J.L.)
| | - Juanying Li
- College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai 201306, China; (Y.T.); (H.X.); (J.L.)
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Liu S, Chen H, Ding Y, Zhou X, Ding Y, Liu S, Ke Z. Thermal aging of polystyrene microplastics within mussels (Mytilus coruscus) under boiling and drying processing. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133282. [PMID: 38142652 DOI: 10.1016/j.jhazmat.2023.133282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/27/2023] [Accepted: 12/13/2023] [Indexed: 12/26/2023]
Abstract
Aged microplastics (MPs) in the environment are a growing concern due to their higher ecological toxicity compared to pristine MPs. While previous studies have explored aging behaviors of MPs under various stress conditions, little is known about their aging during food processing. In this study, we investigated the effects of different thermal food processing methods on the aging of polystyrene (PS) MPs within mussels. We subjected the mussels containing PS MPs to boiling, boiling/solar drying, boiling/hot air drying, and boiling/microwave drying treatments, all of which are common preservation methods used in industry. We analyzed the particle size, surface morphology, yellowing, crystallinity, chemical groups, and hydrophilicity of the PS MPs to understand the aging process. Results show that all processing methods led to aging of PS MPs, with boiling/microwave drying having the most significant impact, followed by boiling/hot air drying, boiling/solar drying, and boiling alone. The aged PS MPs exhibited smaller size, morphological changes, reduced crystallinity, increased yellowness index and carbonyl index, higher presence of O-containing groups, and enhanced hydrophilicity. These findings provide evidence of MPs aging during thermal food processing and emphasize the potential risks associated with this pathway.
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Affiliation(s)
- Siyu Liu
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China
| | - Hui Chen
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China
| | - Yicheng Ding
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China
| | - Xuxia Zhou
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China
| | - Yuting Ding
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China
| | - Shulai Liu
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China
| | - Zhigang Ke
- College of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310014, China; Key Laboratory of Marine Fishery Resources Exploitment & Utilization of Zhejiang Province, Hangzhou 310014, China; National R&D Branch Center for Pelagic Aquatic Products Processing (Hangzhou), Hangzhou 310014, China.
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