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Courtene-Jones W, Burgevin F, Munns L, Shillam MBT, De Falco F, Buchard A, Handy RD, Thompson RC, Hanley ME. Deterioration of bio-based polylactic acid plastic teabags under environmental conditions and their associated effects on earthworms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 934:172806. [PMID: 38772795 DOI: 10.1016/j.scitotenv.2024.172806] [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: 12/19/2023] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 05/23/2024]
Abstract
In response to the plastic waste crisis, teabag producers have substituted the petrochemical-plastic content of their products with bio-based, biodegradable polymers such as polylactic acid (PLA). Despite widespread use, the degradation rate of PLA/PLA-blended materials in natural soil and their effects on soil biota are poorly understood. This study examined the percentage mass deterioration of teabags with differing cellulose:PLA compositions following burial (-10 cm depth) in an arable field margin for 7-months, using a suite of analytical techniques, such as size exclusion chromatography, 1H nuclear magnetic resonance, dynamic scanning calorimetry, and scanning electron microscopy. The effect of 28-d exposure to teabag discs at environmentally relevant concentrations (0.02 %, 0.04 % and 0.07 % w/w) on the survival, growth and reproduction (OECD TG 222 protocol) of the key soil detritivore Eisenia fetida was assessed in laboratory trials. After 7-month burial, Tbag-A (2.4:1 blend) and Tbag-B (3.5:1 cellulose:PLA blend) lost 66 ± 5 % and 78 ± 4 % of their total mass, primarily attributed to degradation of cellulose as identified by FTIR spectroscopy and a reduction in the cellulose:PLA mass ratio, while Tbag-C (PLA) remained unchanged. There were clear treatment and dose-specific effects on the growth and reproductive output of E. fetida. At 0.07 % w/w of Tbag-A adult mortality marginally increased (15 %) and both the quantity of egg cocoons and the average mass of juveniles also increased, while at concentrations ≥0.04 % w/w of Tbag-C, the quantity of cocoons was suppressed. Adverse effects are comparable to those reported for non-biodegradable petrochemical-based plastic, demonstrating that bio-based PLA does not offer a more 'environmentally friendly' alternative. Our study emphasises the necessity to better understand the environmental fate and ecotoxicity of PLA/PLA-blends to ensure interventions developed through the UN Plastic Pollution Treaty to use alternatives and substitutes to conventional plastics do not result in unintended negative consequences.
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Affiliation(s)
- W Courtene-Jones
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK.
| | - F Burgevin
- Institute for Sustainability, Department of Chemistry, University of Bath, Bath BA2 7AY, UK
| | - L Munns
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - M B T Shillam
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - F De Falco
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK; School of Geography, Earth and Environmental Sciences, University of Plymouth, Drake Circus, PL4 8AA Plymouth, Devon, UK
| | - A Buchard
- Institute for Sustainability, Department of Chemistry, University of Bath, Bath BA2 7AY, UK
| | - R D Handy
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - R C Thompson
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
| | - M E Hanley
- School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA, UK
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Zhang Y, Guo J, Sun J, Guan F, Tao J, Song X, Li Z. Bilayer fiber membrane electrospun from polylactic acid/alginate/bromelain and polylactic acid for enhancing the functionality of tea bags. Int J Biol Macromol 2024; 260:129449. [PMID: 38232885 DOI: 10.1016/j.ijbiomac.2024.129449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 01/03/2024] [Accepted: 01/10/2024] [Indexed: 01/19/2024]
Abstract
Tea bags have been extensively used in the food industry and daily life as an efficient way to pack tea. However, the large pores of the commercial tea bags not only lead to the inner contents of tea bag susceptible to bacteria and moisture but also result in the faster water infusion which is undesired during tea brewing. In this study, the polylactic acid (PLA)-PLA/sodium alginate (SA)/bromelain (BL) bilayer fiber membrane imitating the asymmetric wetting structure of lotus leaf blades was fabricated to avoid the above disadvantages of commercial tea bag. The PLA/SA/BL skin-core nanofiber membrane which imitating the skin-core structure of lotus leaf stems was first prepared as the hydrophilic and support layer, then a hydrophobic PLA layer was deposited on top via electrospinning. The PLA-PLA/SA/BL bilayer fiber membrane had a breaking strength of 5.5 MPa and started to decompose at 260 °C. Using this bilayer membrane, tea bags were designed with a novel structure where the hydrophobic PLA layer was placed in the same direction. The novel structure endow the those tea bags a slow and directional water transfer property. Therefore, the PLA-PLA/SA/BL bilayer fiber membrane has great potential for applications as tea bags.
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Affiliation(s)
- Yihang Zhang
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Jing Guo
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China; State Key Laboratory of Bio-Fibers and Eco-Textiles (Qingdao University), Qingdao 266071, China.
| | - Jianbin Sun
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Fucheng Guan
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China.
| | - Jing Tao
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Xuecui Song
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
| | - Zheng Li
- School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China
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Banaei G, García-Rodríguez A, Tavakolpournegari A, Martín-Pérez J, Villacorta A, Marcos R, Hernández A. The release of polylactic acid nanoplastics (PLA-NPLs) from commercial teabags. Obtention, characterization, and hazard effects of true-to-life PLA-NPLs. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:131899. [PMID: 37354720 DOI: 10.1016/j.jhazmat.2023.131899] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 05/30/2023] [Accepted: 06/18/2023] [Indexed: 06/26/2023]
Abstract
This study investigates MNPLs release from commercially available teabags and their effects on both undifferentiated monocultures of Caco-2 and HT29 and in the in vitro model of the intestinal Caco-2/HT29 barrier. Teabags were subjected to mechanical and thermodynamic forces simulating the preparation of a cup of tea. The obtained dispersions were characterized using TEM, SEM, DLS, LDV, NTA, and FTIR. Results confirmed that particles were in the nano-range, constituted by polylactic acid (PLA-NPLs), and about one million of PLA-NPLs per teabag were quantified. PLA-NPLs internalization, cytotoxicity, intracellular reactive oxygen species induction, as well as structural and functional changes in the barrier were assessed. Results show that PLA-NPLs present high uptake rates, especially in mucus-secretor cells, and bio-persisted in the tissue after 72 h of exposure. Although no significant cytotoxicity was observed after the exposure to 100 µg/mL PLA-NPLs during 48 h, a slight barrier disruption could be detected at short-time periods. The present work reveals new insights into the safety of polymer-based teabags, the behavior of true-to-life MNPLs in the human body, as well as new questions on how repeated and prolonged exposures could affect the structure and function of the human intestinal epithelium.
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Affiliation(s)
- Gooya Banaei
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Alba García-Rodríguez
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Alireza Tavakolpournegari
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Juan Martín-Pérez
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Aliro Villacorta
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain; Facultad de Recursos Naturales Renovables, Universidad Arturo Prat, Iquique, Chile
| | - Ricard Marcos
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain.
| | - Alba Hernández
- Group of Mutagenesis, Department of Genetics and Microbiology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain.
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