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Scientific Reports Jun 2023The production of plastic and the amount of waste plastic that enters the ecosystem increases every year. Synthetic plastics gradually break down into particles on the...
The production of plastic and the amount of waste plastic that enters the ecosystem increases every year. Synthetic plastics gradually break down into particles on the micro- and nano-scale in the environment. The micro- and nano-plastics pose a significant ecological threat by transporting toxic chemicals and causing inflammation and cellular damage when ingested; however, removal of those particles from water is challenging using conventional separation methods. Deep eutectic solvents (DES), a new class of solvents composed of hydrogen bond donors and acceptors, have been proposed as a cheaper alternative to ionic liquids. Hydrophobic DES derived from natural compounds (NADES) show promise as extractants in liquid-liquid extractions. This study investigated the extraction efficiency of micro- and nano-plastics including polyethylene terephthalate, polystyrene, and a bioplastic polylactic acid from fresh water and saltwater using three hydrophobic NADES. The extraction efficiencies fall in a range of 50-93% (maximum % extraction) while the extraction rates fall between 0.2 and 1.3 h (as indicated by the time to extract half the theoretical maximum). Molecular simulations show a correlation between the extraction efficiency and the association between the plastics and NADES molecules. This study demonstrates the potential of hydrophobic NADES as extractants for removal of different micro- and nano-plastic particles from aqueous solutions.
Topics: Water; Solvents; Microplastics; Plastics; Ecosystem; Polyethylene Terephthalates
PubMed: 37391491
DOI: 10.1038/s41598-023-37490-6 -
Environmental Research Aug 2023Microplastics (MP) and nanoplastics (NP) contamination of the terrestrial environment is a growing concern worldwide and is thought to impact soil biota, particularly... (Review)
Review
Microplastics (MP) and nanoplastics (NP) contamination of the terrestrial environment is a growing concern worldwide and is thought to impact soil biota, particularly the micro and mesofauna community, by various processes that may contribute to global change in terrestrial systems. Soils act as a long-term sink for MP, accumulating these contaminants and increasing their adverse impacts on soil ecosystems. Consequently, the whole terrestrial ecosystem is impacted by microplastic pollution, which also threatens human health by their potential transfer to the soil food web. In general, the ingestion of MP in different concentrations by soil micro and mesofauna can adversely affect their development and reproduction, impacting terrestrial ecosystems. MP in soil moves horizontally and vertically because of the movement of soil organisms and the disturbance caused by plants. However, the effects of MP on terrestrial micro-and mesofauna are largely overlooked. Here, we give the most recent information on the forgotten impacts of MP contamination of soil on microfauna and mesofauna communities (protists, tardigrades, soil rotifers, nematodes, collembola and mites). More than 50 studies focused on the impact of MP on these organisms between 1990 and 2022 have been reviewed. In general, plastic pollution does not directly affect the survival of organisms, except under co-contaminated plastics that can increase adverse effects (e.g. tire-tread particles on springtails). Besides, they can have adverse effects at oxidative stress and reduced reproduction (protists, nematodes, potworms, springtails or mites). It was observed that micro and mesofauna could act as passive plastic transporters, as shown for springtails or mites. Finally, this review discusses how soil micro- and mesofauna play a key role in facilitating the (bio-)degradation and movement of MP and NP through soil systems and, therefore, the potential transfer to soil depths. More research should be focused on plastic mixtures, community level and long-term experiments.
Topics: Humans; Plastics; Ecosystem; Soil; Microplastics; Food Chain
PubMed: 37244494
DOI: 10.1016/j.envres.2023.116227 -
The Science of the Total Environment Jun 2024Microplastics are a prolific environmental contaminant that have been evidenced in human tissues. Human uptake of microplastic occurs via inhalation of airborne fibres...
Microplastics are a prolific environmental contaminant that have been evidenced in human tissues. Human uptake of microplastic occurs via inhalation of airborne fibres and ingestion of microplastic-contaminated foods and beverages. Plastic and PTFE-coated cookware and food contact materials may release micro- and nanoplastics into food during food preparation. In this study, the extent to which non-plastic, new plastic and old plastic cookware releases microplastics into prepared food is investigated. Jelly is used as a food simulant, undergoing a series of processing steps including heating, cooling, mixing, slicing and storage to replicate food preparation steps undertaken in home kitchens. Using non-plastic cookware did not introduce microplastics to the food simulant. Conversely, using new and old plastic cookware resulted in significant increases in microplastic contamination. Microplastics comprised PTFE, polyethylene and polypropylene particulates and fibrous particles, ranging 13-318 μm. Assuming a meal was prepared daily per the prescribed methodology, new and old plastic cookware may be contributing 2409-4964 microplastics per annum into homecooked food. The health implications of ingesting microplastics remains unclear.
Topics: Microplastics; Food Contamination; Polytetrafluoroethylene; Cooking and Eating Utensils; Environmental Monitoring; Plastics; Cooking
PubMed: 38641111
DOI: 10.1016/j.scitotenv.2024.172577 -
Trends in Biotechnology Mar 2024The design and study of active microbial consortia able to degrade plastics represent an exciting area of research toward the development of bio-based alternatives to...
The design and study of active microbial consortia able to degrade plastics represent an exciting area of research toward the development of bio-based alternatives to efficiently transform plastic waste. This forum article discusses concepts and mechanisms to inform emerging strategies for engineering microbiomes to transform plastics under controlled settings.
Topics: Plastics; Biodegradation, Environmental; Microbiota; Microbial Consortia
PubMed: 37845169
DOI: 10.1016/j.tibtech.2023.09.011 -
Journal of Hazardous Materials Mar 2024Plastic waste released into the environments breaks down into microplastics due to weathering, ultraviolet (UV) radiation, mechanical abrasion, and animal grazing....
Plastic waste released into the environments breaks down into microplastics due to weathering, ultraviolet (UV) radiation, mechanical abrasion, and animal grazing. However, little is known about the plastic fragmentation mediated by microbial degradation. Marine plastic-degrading bacteria may have a double-edged effect in removing plastics. In this study, two ubiquitous marine bacteria, Alcanivorax xenomutans and Halomonas titanicae, were confirmed to degrade polystyrene (PS) and lead to microplastic and nanoplastic generation. Biodegradation occurred during bacterial growth with PS as the sole energy source, and the formation of carboxyl and carboxylic acid groups, decreased heat resistance, generation of PS metabolic intermediates in cultures, and plastic weight loss were observed. The generation of microplastics was dynamic alongside PS biodegradation. The size of the released microplastics gradually changed from microsized plastics on the first day (1344 nm and 1480 nm, respectively) to nanoplastics on the 30th day (614 nm and 496 nm, respectively) by the two tested strains. The peak release from PS films reached 6.29 × 10 particles/L and 7.64 × 10 particles/L from degradation by A. xenomutans (Day 10) and H. titanicae (Day 5), respectively. Quantification revealed that 1.3% and 1.9% of PS was retained in the form of micro- and nanoplastics, while 4.5% and 1.9% were mineralized by A. xenomutans and H. titanicae at the end of incubation, respectively. This highlights the negative effects of microbial degradation, which results in the continuous release of numerous microplastics, especially nanoplastics, as a notable secondary pollution into marine ecosystems. Their fates in the vast aquatic system and their impact on marine lives are noted for further study.
Topics: Animals; Polystyrenes; Microplastics; Plastics; Ecosystem; Water Pollutants, Chemical; Biodegradation, Environmental
PubMed: 38150757
DOI: 10.1016/j.jhazmat.2023.133339 -
The Science of the Total Environment Dec 2023In recent years, significant efforts have been dedicated to measuring and comprehending the impact of microplastics (MPs) in the ocean. Despite harmonization guidelines... (Review)
Review
In recent years, significant efforts have been dedicated to measuring and comprehending the impact of microplastics (MPs) in the ocean. Despite harmonization guidelines for MPs research, discrepancies persist in the applied methodologies and future challenges, mostly for the smaller fractions (< 100 μm). Whether intentional or accidental, ingesting plastic particles by zooplankton can lead to incorporating this pollutant into aquatic food chains. Therefore, zooplankton can serve as a suitable proxy tool for assessing the presence of plastic particles in ocean waters. However, reliable information is essential for conducting experimental laboratory studies on the impact of MPs ingestion by zooplankton organisms. Using zooplankton as a research tool for MPs offers numerous advantages, including similar sampling methodologies and study techniques as MPs and particle data integration over space and time. The scientific community can gain novel perspectives by merging zooplankton studies with MPs research. This review explores key aspects of using zooplankton as a tool for MPs research in water samples, encompassing various views such as particles ingestion in natural environments, particle quantification in zooplankton samples (past and future), ecotoxicological and toxicology model studies. By leveraging the potential of zooplankton research, advancements can be made in developing innovative techniques for MPs analysis.
Topics: Animals; Microplastics; Zooplankton; Plastics; Water Pollutants, Chemical; Environmental Monitoring
PubMed: 37748610
DOI: 10.1016/j.scitotenv.2023.167329 -
Environmental Pollution (Barking, Essex... Aug 2023Human membrane drug transporters are recognized as major actors of pharmacokinetics; they also handle endogenous compounds, including hormones and metabolites. Chemical... (Review)
Review
Human membrane drug transporters are recognized as major actors of pharmacokinetics; they also handle endogenous compounds, including hormones and metabolites. Chemical additives present in plastics interact with human drug transporters, which may have consequences for the toxicokinetics and toxicity of these widely-distributed environmental and/or dietary pollutants, to which humans are highly exposed. The present review summarizes key findings about this topic. In vitro assays have demonstrated that various plastic additives, including bisphenols, phthalates, brominated flame retardants, poly-alkyl phenols and per- and poly-fluoroalkyl substances, can inhibit the activities of solute carrier uptake transporters and/or ATP-binding cassette efflux pumps. Some are substrates for transporters or can regulate their expression. The relatively low human concentration of plastic additives from environmental or dietary exposure is a key parameter to consider to appreciate the in vivo relevance of plasticizer-transporter interactions and their consequences for human toxicokinetics and toxicity of plastic additives, although even low concentrations of pollutants (in the nM range) may have clinical effects. Existing data about interactions of plastic additives with drug transporters remain somewhat sparse and incomplete. A more systematic characterization of plasticizer-transporter relationships is needed. The potential effects of chemical additive mixtures towards transporter activities and the identification of transporter substrates among plasticizers, as well as their interactions with transporters of emerging relevance deserve particular attention. A better understanding of the human toxicokinetics of plastic additives may help to fully integrate the possible contribution of transporters to the absorption, distribution, metabolism and excretion of plastics-related chemicals, as well as to their deleterious effects towards human health.
Topics: Humans; Plastics; Toxicokinetics; Plasticizers; Membrane Transport Proteins; Environmental Pollutants; Drug Interactions
PubMed: 37236587
DOI: 10.1016/j.envpol.2023.121882 -
Food Additives & Contaminants. Part A,... Jul 2023As one of the raw materials of biodegradable food packaging, gelatin is an environmentally friendly substitute for traditional plastic packaging. In this review both... (Review)
Review
As one of the raw materials of biodegradable food packaging, gelatin is an environmentally friendly substitute for traditional plastic packaging. In this review both sources and extraction methods of gelatin are introduced, together with recent modification methods and applications of using plant sources instead of synthetic substances to endow gelatin film with functionality. Gelatin is extracted from mammals, marine organisms, and poultry. Different extraction methods (acid, alkali, enzyme treatment) can affect the molecular weight and amino acid composition of gelatin, thus affecting the molecular structure, physical properties, chemical and functional properties of gelatin. Gelatin serves as a good substrate, but its disadvantage is that it is very brittle. However, the addition of plasticizers can improve the flexibility of the film by reducing chain interactions during the dehydration process. Compared with other plasticizers, glycerol and sorbitol have better effects on adjusting the mechanical properties of gelatin films. Gelatin is combined with active substances such as essential oils, plant extracts, and nanoparticles to prepare gelatin based composite films with good mechanical properties and antibacterial and antioxidant properties. Gelatin-based composite films can effectively inhibit the growth and reproduction of microorganisms and lipid oxidation in food. Applying it to food packaging can improve the quality of fresh food and extend its shelf life.
Topics: Animals; Gelatin; Plasticizers; Anti-Bacterial Agents; Food Packaging; Mammals
PubMed: 37310321
DOI: 10.1080/19440049.2023.2222844 -
Environmental Science and Pollution... Apr 2024Phthalic acid esters (PAEs) are high production volume chemicals used extensively as plasticizers, to increase the flexibility of the main polymer. They are reported to... (Review)
Review
Phthalic acid esters (PAEs) are high production volume chemicals used extensively as plasticizers, to increase the flexibility of the main polymer. They are reported to leach into their surroundings from plastic products and are now a ubiquitous environmental contaminant. Phthalate levels have been determined in several environmental matrices, especially in water. These levels serve as an indicator of plasticizer abuse and plastic pollution, and also serve as a route of exposure to different species including humans. Reports published on effects of different PAEs on experimental models demonstrate their carcinogenic, teratogenic, reproductive, and endocrine disruptive effects. Therefore, regular monitoring and remediation of environmental water samples is essential to ascertain their hazard quotient and daily exposure levels. This review summarises the extraction and detection techniques available for phthalate analysis in water samples such as chromatography, biosensors, immunoassays, and spectroscopy. Current remediation strategies for phthalate removal such as adsorption, advanced oxidation, and microbial degradation have also been highlighted.
Topics: Humans; Esters; Phthalic Acids; Environmental Pollution; Plasticizers; Water; Dibutyl Phthalate; China
PubMed: 38456985
DOI: 10.1007/s11356-024-32670-x -
Waste Management (New York, N.Y.) Mar 2024Plastics and other materials commonly used in horticulture for plant support (e.g. raffia) and soil protection (e.g. mulching film) pose a challenge to achieving a...
Plastics and other materials commonly used in horticulture for plant support (e.g. raffia) and soil protection (e.g. mulching film) pose a challenge to achieving a circular economy. These materials contaminate plant residues, hampering their direct reuse due to the need for separation and cleaning. As a result, contaminated plant residues is often landfilled or incinerated. This study investigates the replacement of conventional plastic raffia and mulching film with biodegradable and compostable alternatives. Polypropylene raffia is compared with a biodegradable viscose polymer and compostable jute fibre, while polyethylene mulching film is compared with a biodegradable polylactic acid film. Conventional and novel alternatives are compared economically using Life-Cycle Costing and environmentally using Life-Cycle Assessment. The economic assessment is based on case studies with two horticultural companies in Almeria (south-eastern Spain), while the environmental analysis uses data from the Ecoinvent database. The use of biodegradable and compostable alternatives for raffia and mulching film proved to be 49% more expensive than conventional options. However, when conventional plastic waste is incinerated rather than landfilled, biodegradable and compostable alternatives have a lower carbon footprint. Although biodegradable and compostable options can be more expensive and have higher impacts in certain situations, proper waste management can lead to environmental benefits. With optimisation and incentives, these alternative options support the transition of horticulture to a sustainable circular economy.
Topics: Soil; Waste Management; Cost-Benefit Analysis; Spain; Plastics
PubMed: 38194799
DOI: 10.1016/j.wasman.2023.12.049