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Zhang C, Liu X, Zhang L, Chen Q, Xu Q. Assessing the aging and environmental implications of polyethylene mulch films in agricultural land. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:1310-1321. [PMID: 38818727 DOI: 10.1039/d4em00102h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2024]
Abstract
Polyethylene mulch films (MFs) are widely employed in agricultural land to enhance crop yield and quality, but the MF residue causes significant environmental concerns. To promote the sustainable application of MFs, it is essential to assess their fate throughout their service life and understand the underlying degradation mechanisms. In this study, surface-exposed and soil-buried MFs were separately collected from agricultural land in Inner Mongolia, China. The variations in aging performance and corresponding property alterations of MF were thoroughly examined. The results indicated that sunlight exposure considerably hastens MF degradation, whereas buried MFs experience a more moderate aging process due to the inhibitory effects of the dark and anaerobic environment on oxidation. Surface cracking was observed in MF-Light samples as a result of photodegradation, while chemical and moisture interactions with soil caused partial perforation in MF-Soil samples. Relative to the pristine MF, the oxidation, unsaturation, and hydroxylation levels of MF-Light increased to 0.88, 0.35, and 0.73, respectively, with corresponding values for MF-Soil at 0.44, 0.13, and 0.24. The generated oxygen-containing functional groups lead to a decrease in contact angles of MF-Light and MF-Soil, enhancing their hydrophilicity. The aging process of MFs led to a decline in mechanical properties, posing challenges for recycling. Moreover, nearly all phthalate esters (PAEs) were released from MFs, regardless of sunlight exposure or soil burial. The use of MFs also impacted the abundance of soil microbial communities. Specifically, the selected polyethylene MF enriched Actinobacteriota by 75%, while reducing Chloroflexi and Firmicutes by 27% and 45%, respectively.
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Affiliation(s)
- Chao Zhang
- Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, Shenzhen, 518055, P. R. China.
| | - Xingyu Liu
- Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, Shenzhen, 518055, P. R. China.
| | - Li Zhang
- Bureau of Agriculture and Livestock, Wongniute, Inner Mongolia, 024500, P. R. China
| | - Qindong Chen
- Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, Shenzhen, 518055, P. R. China.
| | - Qiyong Xu
- Shenzhen Engineering Laboratory for Eco-efficient Recycled Materials, School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, Shenzhen, 518055, P. R. China.
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2
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Zhang L, Wang F, Wang W, Su Y, Zhan M, Lu J, Xie B. Using machine learning to reveal drivers of soil microplastics and assess their stock: A national-scale study. JOURNAL OF HAZARDOUS MATERIALS 2024; 478:135466. [PMID: 39128149 DOI: 10.1016/j.jhazmat.2024.135466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 07/31/2024] [Accepted: 08/08/2024] [Indexed: 08/13/2024]
Abstract
The issue of microplastic (MP) contamination in soil is a significant concern. However, due to limited large-scale studies and stock assessments, our understanding of the drivers of their distribution and fate remains incomplete. To address this, we conducted a comprehensive study in China, collected MP data from 621 sites, and utilized machine learning techniques for analysis. Our findings revealed 9 key factors influencing the distribution of soil MPs, highlighting their nonlinear influence processes. Among these factors, atmospheric deposition emerged as the most dominant driver, while wind and precipitation could lead to the transformation of soil from a sink to a source of MPs. MP concentrations in Chinese soils vary from 1.4 to 4333.1 particles/kg, with human activities significantly affecting their distribution, resulting in higher concentrations in the east and lower concentrations in the west. The estimated MP stock in Chinese soils is 1.92 × 1018 particles, equivalent to a mass of 2.11-8.64 million tonnes. This stock alone surpasses that found in global oceans, making global soil the largest reservoir of MPs. Overall, this study enhances our understanding of the environmental behavior of MPs and provides valuable data and theoretical support for the prevention, control, and management of this contamination.
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Affiliation(s)
- Linjie Zhang
- Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Feng Wang
- Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Wenyue Wang
- Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Yinglong Su
- Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Min Zhan
- Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Jun Lu
- Auckland Bioengineering Institute, University of Auckland, Auckland 1142, New Zealand; Department of Food and Agriculture Technology, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, China
| | - Bing Xie
- Shanghai Engineering Research Center of Biotransformation on Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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3
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Matos AZG, Dias ARDO, Rosa ACFDS, Nascimento Junior RDS, Braz CJDF, Carneiro da Silva LR, de Oliveira AD, Barbosa R, Alves TS. Natural Aging of Reprocessed Polypropylene Composites Filled with Sustainable Corn Fibers. Polymers (Basel) 2024; 16:1788. [PMID: 39000643 PMCID: PMC11243845 DOI: 10.3390/polym16131788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 05/31/2024] [Accepted: 06/10/2024] [Indexed: 07/17/2024] Open
Abstract
Natural fiber reinforcements have the potential to enhance mechanical properties, thereby improving performance and durability in various applications. In this study, we comprehensively evaluated the impact of environmental degradation over 120 days on reprocessed polypropylene (PP) reinforced with corn husk fiber (CHF) composites. The manufactured systems underwent rigorous analysis using various techniques, including Fourier transform infrared spectroscopy, thermogravimetric analysis, optical microscopy, scanning electron microscopy, and tensile testing. These analyses revealed that climatic conditions significantly influenced (p < 0.05) the mechanical properties of all systems. Photodegradation led to surface morphological changes and chemical structures. Regardless, adding CHF filler proved a key factor, as it allowed for less susceptibility to environmental degradation than the reprocessed matrix. These findings, therefore, provide robust evidence supporting the feasibility of using CHF composites for manufacturing agricultural containers.
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Affiliation(s)
- Antonio Zilverlan Germano Matos
- Postgraduate Program in Materials Science and Engineering, Technology Center, Federal University of Piauí, Teresina 64049-550, PI, Brazil; (A.Z.G.M.); (A.R.d.O.D.); (R.d.S.N.J.); (C.J.d.F.B.); (R.B.)
| | - Alisson Rodrigues de Oliveira Dias
- Postgraduate Program in Materials Science and Engineering, Technology Center, Federal University of Piauí, Teresina 64049-550, PI, Brazil; (A.Z.G.M.); (A.R.d.O.D.); (R.d.S.N.J.); (C.J.d.F.B.); (R.B.)
| | | | - Renato de Sousa Nascimento Junior
- Postgraduate Program in Materials Science and Engineering, Technology Center, Federal University of Piauí, Teresina 64049-550, PI, Brazil; (A.Z.G.M.); (A.R.d.O.D.); (R.d.S.N.J.); (C.J.d.F.B.); (R.B.)
| | - Cristiano José de Farias Braz
- Postgraduate Program in Materials Science and Engineering, Technology Center, Federal University of Piauí, Teresina 64049-550, PI, Brazil; (A.Z.G.M.); (A.R.d.O.D.); (R.d.S.N.J.); (C.J.d.F.B.); (R.B.)
| | - Lucas Rafael Carneiro da Silva
- Postgraduate Program in Mining, Metallurgical and Materials Engineering, Federal University of Rio Grande do Sul, Porto Alegre 91501-970, RS, Brazil;
| | - Amanda Dantas de Oliveira
- Postgraduate Program in Materials Science and Engineering, Federal University of Pelotas, Pelotas 96010-610, RS, Brazil;
| | - Renata Barbosa
- Postgraduate Program in Materials Science and Engineering, Technology Center, Federal University of Piauí, Teresina 64049-550, PI, Brazil; (A.Z.G.M.); (A.R.d.O.D.); (R.d.S.N.J.); (C.J.d.F.B.); (R.B.)
| | - Tatianny Soares Alves
- Postgraduate Program in Materials Science and Engineering, Technology Center, Federal University of Piauí, Teresina 64049-550, PI, Brazil; (A.Z.G.M.); (A.R.d.O.D.); (R.d.S.N.J.); (C.J.d.F.B.); (R.B.)
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Yang Z, Zhang J, Haruka N, Murat C, Arakawa H. Spectral analysis of environmental microplastic polyethylene (PE) using average spectra. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:171871. [PMID: 38531446 DOI: 10.1016/j.scitotenv.2024.171871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 03/19/2024] [Accepted: 03/20/2024] [Indexed: 03/28/2024]
Abstract
In this study, microplastic samples from surface seawater of Tokyo Bay were collected, polyethylene (PE) microplastics were used to calculate carbonyl index (CI), and average spectra of PE were analyzed and compared with a previous study applying agitation during chemical treatment. It was found that PE and polypropylene (PP) were the predominant polymer type in the samples. Among PE samples, fragments were the most commonly observed shape, with white being the dominant color. Deviations were found in the average spectra among different shapes and colors when compared to the standard PE spectrum. A comparison of the average spectra between the two datasets suggests that pronounced peaks related to oxidation are most likely resulted from agitation during the chemical treatment. Additionally, it was found a closer spectral resemblance between the sample spectra and the spectrum of standard sample of oxidized PE (PEOx) than with the standard PE spectrum, suggesting that using the oxidized PE as a reference spectrum might be more effective for identification. These findings highlight the complex factors affecting the spectral properties of microplastics and highlight the importance of understanding these variations to enhance the accuracy of microplastic identification workflows and understanding of environmental fate of microplastics.
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Affiliation(s)
- Zijiang Yang
- Faculty of Marine Resources and Environment, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan.
| | - Jiaqi Zhang
- Faculty of Marine Resources and Environment, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan.
| | - Nakano Haruka
- Research Institute for Applied Mechanics, Kyushu University, 6-1 Kasuga-Koen, Kasuga, Fukuoka 816-8580, Japan.
| | - Celik Murat
- Faculty of Marine Resources and Environment, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan
| | - Hisayuki Arakawa
- Faculty of Marine Resources and Environment, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan.
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5
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Maraveas C, Kyrtopoulos IV, Arvanitis KG, Bartzanas T. The Aging of Polymers under Electromagnetic Radiation. Polymers (Basel) 2024; 16:689. [PMID: 38475374 DOI: 10.3390/polym16050689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 02/27/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Polymeric materials degrade as they react with environmental conditions such as temperature, light, and humidity. Electromagnetic radiation from the Sun's ultraviolet rays weakens the mechanical properties of polymers, causing them to degrade. This study examined the phenomenon of polymer aging due to exposure to ultraviolet radiation. The study examined three specific objectives, including the key theories explaining ultraviolet (UV) radiation's impact on polymer decomposition, the underlying testing procedures for determining the aging properties of polymeric materials, and appraising the current technical methods for enhancing the UV resistance of polymers. The study utilized a literature review methodology to understand the aging effect of electromagnetic radiation on polymers. Thus, the study concluded that using additives and UV absorbers on polymers and polymer composites can elongate the lifespan of polymers by shielding them from the aging effects of UV radiation. The findings from the study suggest that thermal conditions contribute to polymer degradation by breaking down their physical and chemical bonds. Thermal oxidative environments accelerate aging due to the presence of UV radiation and temperatures that foster a quicker degradation of plastics.
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Affiliation(s)
- Chrysanthos Maraveas
- Department of Natural Resources Development and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Street, 11855 Athens, Greece
| | - Ioannis Vasileios Kyrtopoulos
- Department of Natural Resources Development and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Street, 11855 Athens, Greece
| | - Konstantinos G Arvanitis
- Department of Natural Resources Development and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Street, 11855 Athens, Greece
| | - Thomas Bartzanas
- Department of Natural Resources Development and Agricultural Engineering, Agricultural University of Athens, 75 Iera Odos Street, 11855 Athens, Greece
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Liang J, Chen X, Duan X, Gu X, Zhao X, Zha S, Chen X. Natural aging and adsorption/desorption behaviors of polyethylene mulch films: Roles of film types and exposure patterns. JOURNAL OF HAZARDOUS MATERIALS 2024; 466:133588. [PMID: 38290328 DOI: 10.1016/j.jhazmat.2024.133588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 01/02/2024] [Accepted: 01/19/2024] [Indexed: 02/01/2024]
Abstract
Polyethylene (PE) mulch films are an important source of microplastics (MPs) in agricultural soils, which may further affect the bioavailability of coexisting pollutants. In this study, white (WM), black (BM), and silver-black (SM) PE mulch films were aged on the soil surface and under soil burial to simulate the two exposure patterns of abandoned mulch films in the field. Results indicated that the soil-surface exposure induced more pronounced aging characteristics, and WM seemed the most susceptible. Serious surface deterioration by aging led to a drastic decrease in the tensile properties of the films, suggesting the tendency to fragment. Oxygen-containing functional groups were generated on the film surfaces, with oxygen/carbon ratios increasing by up to 29 times, which contributed to the prominent increase in Pb adsorption on the film-derived MPs. Additionally, the film surface became more hydrophobic when exposed to the soil surface but more hydrophilic in the soil-burial exposure, which was in agreement with the change in triclosan adsorption, i.e., promotion and suppression, respectively. Aging generally decreased the desorption potential of the adsorbed pollutants in simulated gastrointestinal solutions due to increased interactions. By comparison, exposure patterns were revealed to be the critical factor for these changes, regardless of film types.
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Affiliation(s)
- Jingcheng Liang
- School of Resources and Environmental Engineering, Jiangsu University of Technology, 1801 Zhongwu Avenue, Changzhou 213001, China
| | - Xian Chen
- School of Resources and Environmental Engineering, Jiangsu University of Technology, 1801 Zhongwu Avenue, Changzhou 213001, China.
| | - Xiaotong Duan
- School of Resources and Environmental Engineering, Jiangsu University of Technology, 1801 Zhongwu Avenue, Changzhou 213001, China
| | - Xueyuan Gu
- School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Xiaopeng Zhao
- School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Simin Zha
- School of Resources and Environmental Engineering, Jiangsu University of Technology, 1801 Zhongwu Avenue, Changzhou 213001, China
| | - Xingming Chen
- School of Resources and Environmental Engineering, Jiangsu University of Technology, 1801 Zhongwu Avenue, Changzhou 213001, China
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7
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Ray AS, Rajasekaran M, Uddin M, Kandasamy R. Laccase driven biocatalytic oxidation to reduce polymeric surface hydrophobicity: An effective pre-treatment strategy to enhance biofilm mediated degradation of polyethylene and polycarbonate plastics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166721. [PMID: 37673259 DOI: 10.1016/j.scitotenv.2023.166721] [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: 06/26/2023] [Revised: 08/21/2023] [Accepted: 08/29/2023] [Indexed: 09/08/2023]
Abstract
Plastic pollution is a major global environmental issue due to its structural complexity and poor biodegradability. Biological approaches are appropriate due to cost effectiveness and environmental friendliness, however effective polymer degradation is still in its infancy. As biological treatments are slower than physical and chemical approaches, they could be applied in conjunction with pre-treatment techniques such as photo-oxidation, heat treatment, and chemical treatments. But these processes lead to high energy consumption and hazardous secondary pollution. To address these concerns, an enzymatic pre-treatment strategy has been proposed in this study, with an aim of promoting surface oxidation on the plastics leading to improved hydrophilicity. This in turn, facilitates the surface attachment of microbes, ultimately, accelerating biodegradation. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR) spectroscopy analyses confirmed the surface oxidation of the polyethylene (PE) and polycarbonate (PC) plastics mediated by the action of laccase enzyme. Contact angle measurement witnessed the increased hydrophilicity of the treated plastics. Following, a potential biofilm forming microbial consortium has been employed for the biodegradation of enzyme treated plastics. SEM analysis indicated the increased formation of corrosive pits and surface aberrations on the enzymatically pre-treated plastics and Confocal Laser Scanning microscopy (CLSM) analysis exhibited the enhanced biofilm formation and exopolysaccharide deposition on the pre-treated PE and PC. In addition, X-ray photoelectron spectroscopy (XPS) revealed the reduction in the elemental composition of carbon with an increment in the oxygen composition of plastics. Gel permeation chromatography (GPC) further confirmed the greater reduction in the molecular weights of the plastics subjected to integrated enzymatic and biofilm treatment than only biofilm treated plastics. This is the first report on the integration of enzymatic pre-treatment with the biofilm mediated microbial degradation to achieve enhanced treatment of plastics which demonstrated to be a promising technology for the effective mitigation of plastic pollution.
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Affiliation(s)
- Anindya Shankar Ray
- Industrial and Environmental Sustainability Laboratory, Department of Biotechnology, School of Bioengineering, SRM Institute of science and technology, Kattankulathur-603203, Chengalpattu District, Tamil Nadu, India
| | - Muneeswari Rajasekaran
- Industrial and Environmental Sustainability Laboratory, Department of Biotechnology, School of Bioengineering, SRM Institute of science and technology, Kattankulathur-603203, Chengalpattu District, Tamil Nadu, India
| | - Maseed Uddin
- Industrial and Environmental Sustainability Laboratory, Department of Biotechnology, School of Bioengineering, SRM Institute of science and technology, Kattankulathur-603203, Chengalpattu District, Tamil Nadu, India
| | - Ramani Kandasamy
- Industrial and Environmental Sustainability Laboratory, Department of Biotechnology, School of Bioengineering, SRM Institute of science and technology, Kattankulathur-603203, Chengalpattu District, Tamil Nadu, India.
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8
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Wang T, Liu L, Zhao Q, Meng Z, Li W. The aging of polyethylene mulch films in the presence of cadmium. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 266:115569. [PMID: 37832487 DOI: 10.1016/j.ecoenv.2023.115569] [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: 04/12/2023] [Revised: 09/24/2023] [Accepted: 10/08/2023] [Indexed: 10/15/2023]
Abstract
To determine the fates of the persistent pollutants cadmium (Cd) and micro-plastics in agricultural soils, an in-depth understanding of the interactions between Cd and mulching film is required. In the present work, pot experiments are conducted under natural conditions to study the influence of various Cd concentrations on the aging process of polyethylene mulching film in soil collected from Changzhi, Shanxi Province. The results indicate that during 150 days, the aging degree of the mulch film increases gradually as the increased Cd concentration in the soil. Further, the results of attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectrometry and X-ray photoelectron spectroscopy (XPS) demonstrate that the average vinyl index (VI) of the aging mulch film increases from 1.29 to 1.82, while the oxygen-to-carbon (O/C) ratio of the mulch film decreases significantly from 0.344 to 0.045, as the Cd concentration is increased from 0 to 10 mg kg-1. When the aging time exceeds 90 days, the oxygen-containing functional groups (C-O and CO) generated consumed by the adsorbed Cd. In addition, electron paramagnetic resonance (EPR) measurements indicate that Cd both enhances the formation of hydroxyl radical (·OH) on the surface of the mulch film and prevents the combination of ·OH and electrons, thereby accelerating the aging of the mulch. Hence, the present study indicates that the presence of Cd will hasten the decomposition of mulch, which will inevitably result in the faster release of micro-plastics from the mulch into the soil environment.
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Affiliation(s)
- Teng Wang
- Department of Life Science, Changzhi University, Changzhi, Shanxi 046011, PR China
| | - Lin Liu
- Department of Life Science, Changzhi University, Changzhi, Shanxi 046011, PR China; Shanxi Agricultural University, Eco-Environment Industrial Technology Research Institute, Taigu, Shanxi 030801, PR China.
| | - Qingsong Zhao
- Department of Life Science, Changzhi University, Changzhi, Shanxi 046011, PR China
| | - Zhaofu Meng
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shannxi 712100, PR China; Key Lab of Nutrition and Agro-environment in Northwest China, Ministry of Agriculture, Yangling, Shannxi 712100, PR China
| | - Wenbin Li
- College of Environmental Science and Engineering, China West Normal University, Nanchong, Sichuan 637009, PR China
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9
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Vlachogianni T, Scoullos M. Assessing marine macrolitter on the coastline of the Asterousia Biosphere Reserve: Insights from a community-based study. MARINE POLLUTION BULLETIN 2023; 195:115474. [PMID: 37672921 DOI: 10.1016/j.marpolbul.2023.115474] [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: 07/25/2023] [Revised: 08/26/2023] [Accepted: 08/29/2023] [Indexed: 09/08/2023]
Abstract
Even in pristine and remote environments of the Mediterranean, marine litter is building up threatening habitats and species and inhibiting sustainable development. The present study reports the findings of beach litter surveys carried out by 250 local community members in nine sites along the coastline of the Asterousia Biosphere Reserve, situated in the southernmost end of Europe. The average recorded litter density along these sites amounted to 125 items per 100 meters of coastline (range: 22-510) and to 0.05 items per square meter of beach (range: 0.01-0.13). Only two of the nine surveyed beaches were found to be in good environmental status, in compliance with the European threshold value for beach litter. The other seven studied beaches surpassed the European threshold value. The primary sources of the litter identified in the study can be attributed to unsustainable practices and inadequate waste management by individuals, communities and municipalities using the coastal and marine environment. Additionally, unsustainable waste management practices within the agricultural sector were also found to be a significant contributor to marine litter pollution.
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Affiliation(s)
- Thomais Vlachogianni
- Mediterranean Information Office for Environment, Culture and Sustainable Development, Athens, Greece.
| | - Michael Scoullos
- Mediterranean Information Office for Environment, Culture and Sustainable Development, Athens, Greece; Laboratory of Environmental Chemistry, Faculty of Chemistry, University of Athens, Greece
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10
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Noro K, Kakimoto Y, Wang Q, Akiyama S, Takikawa T, Omagari R, Yabuki Y, Amagai T. Enhancement of photodegradation of polyethylene with adsorbed polycyclic aromatic hydrocarbons under artificial sunlight irradiation. MARINE POLLUTION BULLETIN 2023; 194:115331. [PMID: 37499570 DOI: 10.1016/j.marpolbul.2023.115331] [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: 04/26/2023] [Revised: 07/15/2023] [Accepted: 07/20/2023] [Indexed: 07/29/2023]
Abstract
The photodegradation of plastic waste produces microplastics (MPs) in marine environments. Plastics can adsorb hydrophobic organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and can be transported over long distances. However, the impact of adsorbed pollutants on the photodegradation remains unknown. Here, we show that adsorbed PAHs act as photocatalysts that promote the photodegradation of polyethylene. Upon light irradiation, coloration and surface degradation of the PAH-adsorbed polyethylene sheets were observed, indicating that the PAH-adsorbed polyethylene sheets are less resistant to light. Furthermore, fluorene, phenanthrene, anthracene, benzo[a]anthracene, benzo[a]pyrene, and indeno[1,2,3-cd]perylene adsorbed on polyethylene MP exhibited lower photodegradation rates than the aqueous phase. These results indicate that these PAHs can act as photocatalysts; their role of PAHs may have two adverse effects on marine environment. First, enhanced photodegradation of plastic waste increased the production of MPs. Second, the lifetime of PAHs is extended, thereby enhancing PAHs pollution in marine environments.
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Affiliation(s)
- Kazushi Noro
- University of Shizuoka, Suruga-ku, Shizuoka 422-8526, Japan.
| | - Yuna Kakimoto
- University of Shizuoka, Suruga-ku, Shizuoka 422-8526, Japan
| | - Qi Wang
- National Institute of Occupational Safety and Health, Japan, Nagao 6-21-1, Tama-Ku, Kawasaki 214-8585, Japan
| | - Satoshi Akiyama
- Research Institute of Environment, Agriculture and Fisheries, Osaka Prefecture, Habikino, Osaka 583-0862, Japan
| | | | - Ryo Omagari
- University of Shizuoka, Suruga-ku, Shizuoka 422-8526, Japan
| | - Yoshinori Yabuki
- Research Institute of Environment, Agriculture and Fisheries, Osaka Prefecture, Habikino, Osaka 583-0862, Japan
| | - Takashi Amagai
- University of Shizuoka, Suruga-ku, Shizuoka 422-8526, Japan
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11
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Zou W, Lu S, Wang J, Xu Y, Shahid MA, Saleem MU, Mehmood K, Li K. Environmental Microplastic Exposure Changes Gut Microbiota in Chickens. Animals (Basel) 2023; 13:2503. [PMID: 37570310 PMCID: PMC10417107 DOI: 10.3390/ani13152503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 07/27/2023] [Accepted: 07/28/2023] [Indexed: 08/13/2023] Open
Abstract
As novel environmental contaminants, MPs exist widely in the environment and accumulate in organisms, which has become a global ecological problem. MP perturbations of organismal physiology and behavior have been extensively recorded in aquatic animals, but the potential effects of MPs on poultry are not well characterized. Here, we explored the adverse effects of MP exposure on the growth performance and gut microbiota of chickens. Results showed that the growth performance of chickens decreased significantly during MP exposure. Additionally, Firmicutes, Bacteroidota, and Proteobacteria were found to be dominant in the gut microbiota of MP-exposed chickens, regardless of health status. Although the types of dominant bacteria did not change, the abundances of some bacteria and the structure of the gut microbiota changed significantly. Compared with the controls, the alpha diversity of gut microbiota in chickens exposed to MPs showed a significant decrease. The results of comparative analyses of bacteria between groups showed that the levels of 1 phyla (Proteobacteria) and 18 genera dramatically decreased, whereas the levels of 1 phyla (Cyanobacteria) and 12 genera dramatically increased, during MP exposure. In summary, this study provides evidence that exposure to MPs has a significant impact on the growth performance and gut microbial composition and structure of chickens, leading to a gut microbial imbalance. This may raise widespread public concern about the health threat caused by MP contamination, which is relevant to the maintenance of environmental quality and protection of poultry health.
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Affiliation(s)
- Wen Zou
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; (W.Z.); (S.L.); (J.W.); (Y.X.)
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Sijia Lu
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; (W.Z.); (S.L.); (J.W.); (Y.X.)
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Jia Wang
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; (W.Z.); (S.L.); (J.W.); (Y.X.)
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Yixiao Xu
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; (W.Z.); (S.L.); (J.W.); (Y.X.)
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
| | - Muhammad Akbar Shahid
- Department of Pathobiology, Faculty of Veterinary Sciences, Bahauddin Zakariya University, Multan 60800, Pakistan;
| | - Muhammad Usman Saleem
- Department of Biosciences, Faculty of Veterinary Sciences, Bahauddin Zakariya University, Multan 60800, Pakistan;
| | - Khalid Mehmood
- Faculty of Veterinary and Animal Sciences, The Islamia University of Bahawalpur, Bahawalpur 63100, Pakistan;
| | - Kun Li
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; (W.Z.); (S.L.); (J.W.); (Y.X.)
- MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China
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12
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Qiu Y, Zhang T, Zhang P. Fate and environmental behaviors of microplastics through the lens of free radical. JOURNAL OF HAZARDOUS MATERIALS 2023; 453:131401. [PMID: 37086675 DOI: 10.1016/j.jhazmat.2023.131401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/04/2023] [Accepted: 04/11/2023] [Indexed: 05/03/2023]
Abstract
Microplastics (MPs), as plastics with a size of less than 5 mm, are ubiquitously present in the environment and become an increasing environmental concern. The fate and environmental behavior of MPs are significantly influenced by the presence of free radicals. Free radicals can cause surface breakage, chemical release, change in crystallinity and hydrophilicity, and aggregation of MPs. On the other hand, the generation of free radicals with a high concentration and oxidation potential can effectively degrade MPs. There is a limited review article to bridge the fate and environmental behaviors of MP with free radicals and their reactions. This paper reviews the sources, types, detection methods, generation mechanisms, and influencing factors of free radicals affecting the environmental processes of MPs, the environmental effects of MPs controlled by free radicals, and the degradation strategies of MPs based on free radical-associated technologies. Moreover, this review elaborates on the limitations of the current research and provides ideas for future research on the interactions between MPs and free radicals to better explain their environmental impacts and control their risks. This article aims to keep the reader abreast of the latest development in the fate and environmental behaviors of MP with free radicals and their reactions and to bridge free radical chemistry with MP control methodology.
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Affiliation(s)
- Ye Qiu
- College of Environmental Science and Engineering, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, 38 Tongyan Rd., Tianjin 300350, China; Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Taipa, Macao Special Administrative Region of China
| | - Tong Zhang
- College of Environmental Science and Engineering, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, 38 Tongyan Rd., Tianjin 300350, China.
| | - Ping Zhang
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Taipa, Macao Special Administrative Region of China.
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13
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Wang H, Zhu J, He Y, Wang J, Zeng N, Zhan X. Photoaging process and mechanism of four commonly commercial microplastics. JOURNAL OF HAZARDOUS MATERIALS 2023; 451:131151. [PMID: 36889070 DOI: 10.1016/j.jhazmat.2023.131151] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/21/2023] [Accepted: 03/03/2023] [Indexed: 06/18/2023]
Abstract
Microplastics (MPs) are the widespread emerging pollutants in the terrestrial systems, and photo-oxidation is an effective process for aging MPs on land. Here, four common commercial MPs were exposed to ultraviolet (UV) light to simulate the photo-aging of MPs on soil, and the changes in surface properties and eluates of photoaging MPs were studied. Results revealed that polyvinyl chloride (PVC) and polystyrene (PS) exhibited more pronounced physicochemical changes than polypropylene (PP) and polyethylene (PE) during photoaging on the simulated topsoil, due to the dechlorination of PVC and the debenzene ring of PS. Oxygenated groups accumulated in aged MPs were strongly correlated with dissolved organic matters (DOMs) leaching. Through analysis of the eluate, we found that photoaging altered the molecular weight and aromaticity of DOMs. PS-DOMs showed the greatest increase in humic-like substances after aging, whereas PVC-DOMs exhibited the highest amount of additive leaching. The chemical properties of additives explained their differences in photodegradation responses, which also accounted for the greater importance of chemical structure of MPs to their structural stability. These findings demonstrate that the extensive presence of cracks in aged MPs facilitates DOMs formation and the complexity of DOMs composition poses a potential threat to soil and groundwater safety.
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Affiliation(s)
- Huiqian Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, People's Republic of China; Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, United States
| | - Jiahui Zhu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, People's Republic of China
| | - Yuan He
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, People's Republic of China
| | - Jiawei Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, People's Republic of China
| | - Nengde Zeng
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, People's Republic of China
| | - Xinhua Zhan
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu Province 210095, People's Republic of China.
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Li J, Yin K, Hou L, Zhang Y, Lu H, Ma C, Xing M. Polystyrene microplastics mediate inflammatory responses in the chicken thymus by Nrf2/NF-κB pathway and trigger autophagy and apoptosis. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 100:104136. [PMID: 37127111 DOI: 10.1016/j.etap.2023.104136] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 03/15/2023] [Accepted: 04/28/2023] [Indexed: 05/03/2023]
Abstract
Microplastics (MPs) are now a hot environmental contaminant. However, researchers paid little attention to their effects on immune organs such as the thymus. Here, we exposed chickens to a concentration gradient of polystyrene microplastics (PS-MPs) and then followed the decrease in the thymus index. HE staining showed cellular infiltration in the thymus. The assay kit corroborated that PS-MPs impelled oxidative stress in the thymus: increased MDA levels, downregulated antioxidants such as SOD, CAT, and GSH, and significantly undermined total antioxidant capacity. Western blotting and qRT-PCR results showed that Nrf2/NF-κB, Bcl-2/Bax, and AKT signaling pathways were activated in the thymus after exposure to PS-MPs. It stimulated the increased expression of downstream such as IL-1β, caspase-3, and Beclin1, triggering thymus inflammation, apoptosis, and autophagy. This study provides new insights into the field of microplastic immunotoxicity and highlights potential environmental hazards in poultry farming.
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Affiliation(s)
- Junbo Li
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China
| | - Kai Yin
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China
| | - Lulu Hou
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China
| | - Yue Zhang
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China
| | - Hongmin Lu
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China
| | - Chengxue Ma
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China.
| | - Mingwei Xing
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin 150040, Heilongjiang, PR China.
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15
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Xiong XB, Zhao ZY, Wang PY, Zhou R, Cao J, Wang J, Wesly K, Wang WL, Wang N, Hao M, Wang YB, Tao HY, Xiong YC. In situ degradation of low-density polyethylene film in irrigation maize field: Thickness-dependent effect. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159999. [PMID: 36368391 DOI: 10.1016/j.scitotenv.2022.159999] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 10/05/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
Thickness of low-density polyethylene (LDPE) film might determine its mechanical strength, clean production and soil health. Yet, this issue is little understood. In situ aging effects were evaluated in LDPE films with the thickness of 0.006 mm, 0.008 mm, 0.010 mm and 0.015 mm in maize field. The data showed that maximum tensile force (TFmax), maximum tensile strength (TSmax) and elongation at break (EAB) were massively lowered with increasing thickness after aging. The greatest and lowest reduction magnitude of EAB was 27.6 % and 11.2 % in 0.006 mm and 0.015 mm films respectively. Also, the melting point (Tm) and crystallinity (Xc) under Differential Scanning Calorimeter (DSC) tended to decline with the increasing thickness. Moreover, the peak intensity of crystalline regions tended to transfer and concentrate on the amorphous regions, and such tendency became more pronounced in the thin films. Interestingly, there existed a pronounced distinct thickness-dependent effects on soil bulk density (SBD) and soil water-stable aggregate proportion. Thick plastic film mulching increased SBD but reduced the proportion of macroaggregates (mainly referred to 0.015 mm and 0.010 mm). In addition, thick film mulching slightly reduced the levels of soil organic carbon (SOC) and total nitrogen (TN), but significantly promoted the contents of soil labile C and N. Particularly, it significantly promoted above- & under-ground biomass of maize across two growing seasons (p < 0.05). To sum up, thickening LDPE film may act as a promising solution to improve LDPE film residue recycling, while benefiting for higher productivity. However, thick film mulching may cause a certain adverse impact on soil structure, and further investigations would be needed in the future.
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Affiliation(s)
- Xiao-Bin Xiong
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Ze-Ying Zhao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Peng-Yang Wang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Rui Zhou
- School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
| | - Jing Cao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Jing Wang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China; Gansu Key Laboratory of Resource Utilization of Agricultural Solid Wastes, Tianshui Normal University, Tianshui 741000, China
| | - Kiprotich Wesly
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Wen-Li Wang
- School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China
| | - Ning Wang
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Meng Hao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - Yi-Bo Wang
- Gansu Key Laboratory of Resource Utilization of Agricultural Solid Wastes, Tianshui Normal University, Tianshui 741000, China
| | - Hong-Yan Tao
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China
| | - You-Cai Xiong
- State Key Laboratory of Grassland Agro-ecosystems, College of Ecology, Lanzhou University, Lanzhou 730000, PR China.
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Herath A, Salehi M. Studying the combined influence of microplastics' intrinsic and extrinsic characteristics on their weathering behavior and heavy metal transport in storm runoff. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 308:119628. [PMID: 35716893 DOI: 10.1016/j.envpol.2022.119628] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 05/25/2022] [Accepted: 06/12/2022] [Indexed: 06/15/2023]
Abstract
The weathering and contaminant transport behavior of both primary (PMPs) and secondary microplastics (SMPs) are interrelated to their original physiochemical features and variations within the environment. This study examines the influence of PMPs' intrinsic characteristics (polymer structure and crystallinity) and SMPs' extrinsic features (surface oxidation and external sediments attachment) on the photodegradation kinetics, and subsequently Pb(II) and Zn(II) uptake from stormwater. For this purpose, high density polyethylene (HDPE) and low density polyethylene (LDPE) with different degrees of crystallinities were produced as PMPs, and their photodegradation behaviors were compared with original polymers. Furthermore, the SMPs generated by abrasion and surface oxidation of PMPs and the virgin PMPs underwent accelerated photodegradation, and the changes of their crystallinity, surface chemistry, and morphology were examined. Scanning electron microscopy (SEM) imaging and X-ray photoelectron (XPS) studies revealed the formation of cracks and different oxidized functionalities on MPs surface due to UV photodegradation. The vinyl and carbonyl indices calculated using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy demonstrated an elevated photodegradation rate for SMPs compared to the PMPs. Moreover, the Differential Scanning Colorimetry (DSC) demonstrated an increasing percentage of crystallinity in all MPs due to the photodegradation. The percent crystallinity of HDPE pellets increased after photodegradation from 49.8 to 62.6 and it increased from 17.2 to 38.9 for LDPE pellets respectively. The greater level of increase in crystallinity for LDPE in comparison to HDPE upon photodegradation was referred to as LDPE's greater amorphous content and branched structure. A greater level of metal uptake was obtained for photodegraded LDPE pellets as 2526 μg/m2 for Pb(II) and 2028 μg/m2 for Zn(II) respectively.
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Affiliation(s)
- Amali Herath
- Department of Civil Engineering, The University of Memphis, Memphis, TN, USA
| | - Maryam Salehi
- Department of Civil Engineering, The University of Memphis, Memphis, TN, USA.
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