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Environmental Pollution (Barking, Essex... Oct 2023Never as today the need for collaborative interactions between industry, the scientific community, NGOs, policy makers and citizens has become crucial for the... (Review)
Review
Never as today the need for collaborative interactions between industry, the scientific community, NGOs, policy makers and citizens has become crucial for the development of shared political choices and protection of the environment, for the safeguard of future generations. The complex socio-economic and environmental interconnections that underlie the EU strategy of the last years, within the framework of the Agenda 2030 and the green deal, often create perplexity and confusion that make difficult to outline the definition of a common path to achieve carbon neutrality and "net zero emissions" by 2050. Scope of this work is to give a general overview of EU policies, directives, regulations, and laws concerning polymers and plastic manufacturing, aiming to reduce plastic pollution, allowing for a better understanding of the implications that environmental concern and protection may generate from a social-economical point of view.
Topics: Plastics; Environmental Pollution
PubMed: 37414120
DOI: 10.1016/j.envpol.2023.122102 -
Environmental Science & Technology Jun 2024Microplastics are routinely ingested and inhaled by humans and other organisms. Despite the frequency of plastic exposure, little is known about its health consequences....
Microplastics are routinely ingested and inhaled by humans and other organisms. Despite the frequency of plastic exposure, little is known about its health consequences. Of particular concern are plastic additives─chemical compounds that are intentionally or unintentionally added to plastics to improve functionality or as residual components of plastic production. Additives are often loosely bound to the plastic polymer and may be released during plastic exposures. To better understand the health effects of plastic additives, we performed a comprehensive literature search to compile a list of 2,712 known plastic additives. Then, we performed an integrated toxicogenomic analysis of these additives, utilizing cancer classifications and carcinogenic expression pathways as a primary focus. Screening these substances across two chemical databases revealed two key observations: (1) over 150 plastic additives have known carcinogenicity and (2) the majority (∼90%) of plastic additives lack data on carcinogenic end points. Analyses of additive usage patterns pinpointed specific polymers, functions, and products in which carcinogenic additives reside. Based on published chemical-gene interactions, both carcinogenic additives and additives with unknown carcinogenicity impacted similar biological pathways. The predominant pathways involved DNA damage, apoptosis, the immune response, viral diseases, and cancer. This study underscores the urgent need for a systematic and comprehensive carcinogenicity assessment of plastic additives and regulatory responses to mitigate the potential health risks of plastic exposure.
Topics: Plastics; Carcinogens; Humans; Microplastics
PubMed: 38830620
DOI: 10.1021/acs.est.3c06840 -
Environment International Sep 2023Plastic particles are found almost ubiquitously in the environment and can get ingested orally by humans. We have used food-relevant microplastics (2 µm polylactic...
Plastic particles are found almost ubiquitously in the environment and can get ingested orally by humans. We have used food-relevant microplastics (2 µm polylactic acid), submicroplastics (250 nm polylactic acid and 366 nm melamine formaldehyde resin) and nanoplastics (25 nm polymethylmethacrylate) to study material- and size-dependent uptake and transport across the human intestinal barrier and liver. Therefore, different Transwell™-based in vitro (co-)culture models were used: Differentiated Caco-2 cells mimicking the intestinal enterocyte monolayer, an M-cell model complementing the Caco-2 monoculture with antigen uptake-specialized cells, a mucus model complementing the barrier with an intestinal mucus layer, and an intestinal-liver co-culture combining differentiated Caco-2 cells with differentiated HepaRG cells. Using these complex barrier models, uptake and transport of particles were analyzed based on the fluorescence of the particles using confocal microscopy and a fluorescence-based quantification method. Additionally, the results were verified by Time-of-Flight - Secondary Ion Mass Spectrometry (ToF-SIMS) analysis. Furthermore, an effect screening at the mRNA level was done to investigate oxidative stress response, inflammation and changes to xenobiotic metabolism in intestinal and hepatic cells after exposure to plastic particles. Oxidative stress and inflammation were additionally analyzed using a flow-cytometric assay for reactive oxygen species and cytokine measurements. The results reveal a noteworthy uptake into and transport of microplastic and submicroplastic particles across the intestinal epithelium. Particularly, we show a pronounced uptake of particles into liver cells after crossing of the intestinal epithelium, using the intestinal-liver co-culture. The particles evoke some alterations in xenobiotic metabolism, but did not cause increased oxidative stress or inflammatory response on protein level. Taken together, these complex barrier models can be applied on micro-, submicro- and nanoplastics and reveal information in particle uptake, transport and cellular impact.
Topics: Humans; Microplastics; Plastics; Caco-2 Cells; Xenobiotics; Liver; Inflammation
PubMed: 37657408
DOI: 10.1016/j.envint.2023.108172 -
The Science of the Total Environment Jul 2023Plastic waste is ubiquitous in the environment and can become colonised by distinct microbial biofilm communities, known collectively as the 'plastisphere.' The...
Plastic waste is ubiquitous in the environment and can become colonised by distinct microbial biofilm communities, known collectively as the 'plastisphere.' The plastisphere can facilitate the increased survival and dissemination of human pathogenic prokaryotes (e.g., bacteria); however, our understanding of the potential for plastics to harbour and disseminate eukaryotic pathogens is lacking. Eukaryotic microorganisms are abundant in natural environments and represent some of the most important disease-causing agents, collectively responsible for tens of millions of infections, and millions of deaths worldwide. While prokaryotic plastisphere communities in terrestrial, freshwater, and marine environments are relatively well characterised, such biofilms will also contain eukaryotic species. Here, we critically review the potential for fungal, protozoan, and helminth pathogens to associate with the plastisphere, and consider the regulation and mechanisms of this interaction. As the volume of plastics in the environment continues to rise there is an urgent need to understand the role of the plastisphere for the survival, virulence, dissemination, and transfer of eukaryotic pathogens, and the effect this can have on environmental and human health.
Topics: Humans; Plastics; Public Health; Environmental Pollution; Eukaryota; Bacteria
PubMed: 36996975
DOI: 10.1016/j.scitotenv.2023.163093 -
Environmental Research Nov 2023Bioplastics arise as an alternative to plastic production delinked from fossil resources. However, as their demand is increasing, there is a need to investigate their...
Bioplastics arise as an alternative to plastic production delinked from fossil resources. However, as their demand is increasing, there is a need to investigate their environmental fingerprint. Here we study the toxicity of microplastics (MPLs) of two widely used materials, the polylactic acid (PLA) and the polyhydroxybutyrate (PHB) on the environmental aquatic model species Daphnia magna. The study was focused on sublethal behavioural and feeding endpoints linked to antipredator scape responses and food intake. The study aimed to test that MPLs from single-use household comercial items and among them bioplastics should be more toxic than those obtained from standard plastic polymers and fossil plastic materials due to the greater amount of plastic additives, and that MPLs should be more toxic than plastic extracts due to the contribution of both particle and plastic additive toxicity. MPLs were obtained by cryogenic grinding and sea-sand erosion to obtain irregular particles. MPL included standard polymers and nine comercial items of PLA and PHB and one fossil-based material of high-density polyethylene (HDPE). The additive content in commercial items was characterised by liquid chromatography coupled with high-resolution mass spectrometry. D. magna juveniles were exposed for 24 h to particles and their plastic extracts. Results indicated that the toxicity of bioplastic particles was five times higher than the effects produced by exposure to the content of the additives alone, that bioplastic particles were more toxic than fossil ones and that particles obtained from commercial items were more toxic than those obtained from PLA, PHB or HDPE polymer standards. Predicted toxicity from the measured plastic additives in the studied commercially available household items, however, was poorly related with the observed behavioural and feeding effects. Further research on unknown chemical components together with physical factors is need it to fully understand the mechanisms of toxicity of bioplastic materials.
Topics: Animals; Microplastics; Plastics; Daphnia; Polyethylene; Polyesters; Biopolymers; Water Pollutants, Chemical
PubMed: 37517491
DOI: 10.1016/j.envres.2023.116775 -
Protein Engineering, Design & Selection... Jan 2024Plastic degrading enzymes have immense potential for use in industrial applications. Protein engineering efforts over the last decade have resulted in considerable... (Review)
Review
Plastic degrading enzymes have immense potential for use in industrial applications. Protein engineering efforts over the last decade have resulted in considerable enhancement of many properties of these enzymes. Directed evolution, a protein engineering approach that mimics the natural process of evolution in a laboratory, has been particularly useful in overcoming some of the challenges of structure-based protein engineering. For example, directed evolution has been used to improve the catalytic activity and thermostability of polyethylene terephthalate (PET)-degrading enzymes, although its use for the improvement of other desirable properties, such as solvent tolerance, has been less studied. In this review, we aim to identify some of the knowledge gaps and current challenges, and highlight recent studies related to the directed evolution of plastic-degrading enzymes.
Topics: Directed Molecular Evolution; Protein Engineering; Plastics; Polyethylene Terephthalates; Enzymes
PubMed: 38713696
DOI: 10.1093/protein/gzae009 -
Microbiology Spectrum Aug 2023Over half of the world's plastic waste is landfilled, where it is estimated to take hundreds of years to degrade. Given the continued use and disposal of plastic...
Over half of the world's plastic waste is landfilled, where it is estimated to take hundreds of years to degrade. Given the continued use and disposal of plastic products, it is vital that we develop fast and effective ways to utilize plastic waste. Here, we explore the potential of tandem chemical and biological processing to process various plastics quickly and effectively. Four samples of compost or sediment were used to set up enrichment cultures grown on mixtures of compounds, including disodium terephthalate and terephthalic acid (monomers of polyethylene terephthalate), compounds derived from the chemical deconstruction of polycarbonate, and pyrolysis oil derived from high-density polyethylene plastics. Established enrichment communities were also grown on individual substrates to investigate the substrate preferences of different taxa. Biomass harvested from the cultures was characterized using 16S rRNA gene amplicon sequencing and shotgun metagenomic sequencing. These data reveal low-diversity microbial communities structured by differences in culture inoculum, culture substrate source plastic type, and time. Microbial populations from the classes , , , and were significantly enriched when grown on substrates derived from high-density polyethylene and polycarbonate. The metagenomic data contain abundant aromatic and aliphatic hydrocarbon degradation genes relevant to the biodegradation of deconstructed plastic substrates used here. We show that microbial populations from diverse environments are capable of growth on substrates derived from the chemical deconstruction or pyrolysis of multiple plastic types and that paired chemical and biological processing of plastics should be further developed for industrial applications to manage plastic waste. The durability and impermeable nature of plastics have made them a popular material for numerous applications, but these same qualities make plastics difficult to dispose of, resulting in massive amounts of accumulated plastic waste in landfills and the natural environment. Since plastic use and disposal are projected to increase in the future, novel methods to effectively break down and dispose of current and future plastic waste are desperately needed. We show that the products of chemical deconstruction or pyrolysis of plastic can successfully sustain the growth of low-diversity microbial communities. These communities were enriched from multiple environmental sources and are capable of degrading complex xenobiotic carbon compounds. This study demonstrates that tandem chemical and biological processing can be used to degrade multiple types of plastics over a relatively short period of time and may be a future avenue for the mitigation of rapidly accumulating plastic waste.
Topics: Plastics; Polyethylene; RNA, Ribosomal, 16S; Polyethylene Terephthalates; Bacteria
PubMed: 37260392
DOI: 10.1128/spectrum.00362-23 -
The Science of the Total Environment Sep 2023For the past two decades, with the increase in plastic consumption came a rise in plastic waste, with the bulk of it ending up in landfills, incinerated, recycled or... (Review)
Review
For the past two decades, with the increase in plastic consumption came a rise in plastic waste, with the bulk of it ending up in landfills, incinerated, recycled or leaking into the environment, especially in aquatic ecosystems. Plastic waste poses a significant environmental threat and a wealth issue due to its non-biodegradability and recalcitrant nature. Polyethylene (PE) remains one of the major utilized polymers in different applications amid all the other types because of its low production costs, simplistic nature prone to be modified and historically predominant researched material. Since the common methods for plastic disposal are troubled by limitations, there is a growing need for more appropriate and environment friendly methods alternatives. This study highlights several ways that can be used to assist PE (bio)degradation and mitigate its waste impact. Biodegradation (microbiological activity driven) and photodegradation (radiation driven) are the most promising for PE waste control. The shape of the material (powder, film, particles, etc.), the composition of medium, additives and pH, temperature and incubation or exposure times contribute to plastic degradation efficiency. Moreover, radiation pretreatment can enhance the biodegradability of PE, providing a promising approach to fighting plastic pollution. This paper relates the most significant results regarding PE degradation studies followed by weight loss analysis, surface morphology changes, oxidation degree (for photodegradation) and mechanical properties assessment. All combined strategies are very promising to minimize the polyethylene impact. However, there is still a long way to go through. The degradation kinetics is still low for the currently available biotic or abiotic processes, and complete mineralization is thoroughly unseen.
Topics: Polyethylene; Ecosystem; Plastics; Polymers; Biodegradation, Environmental
PubMed: 37285989
DOI: 10.1016/j.scitotenv.2023.164629 -
Molecules (Basel, Switzerland) Jun 2023In the process of production, processing, transportation, and storage of edible oils, the oils inevitably come into contact with plastic products. As a result,... (Review)
Review
In the process of production, processing, transportation, and storage of edible oils, the oils inevitably come into contact with plastic products. As a result, plasticizers migrate into edible oils, are harmful to human health, and can exhibit reproductive toxicity. Therefore, the determination of plasticizers in edible oils is very important, and a series of sample preparation methods and determination techniques have been developed for the determination of plasticizers in edible oils. Phthalic acid ester (PAE) plasticizers are the most widely used among all plasticizers. This review aims to provide a comprehensive overview of the sample preparation methods and detection techniques reported for the determination of PAEs in edible oils since 2010, focusing on sample preparation methods of edible oils combined with various separation-based analytical techniques, such as gas chromatography (GC) and liquid chromatography (LC) with different detectors. Furthermore, the advantages, disadvantages, and limitations of these techniques as well as the prospective future developments are also discussed.
Topics: Humans; Plasticizers; Phthalic Acids; Plant Oils; Esters
PubMed: 37446766
DOI: 10.3390/molecules28135106 -
Environmental Science and Pollution... Jul 2023Since first being introduced for public use in the 1960s, plastic has become one of the most pervasive and ubiquitous forms of pollution globally. The potential fate and...
Since first being introduced for public use in the 1960s, plastic has become one of the most pervasive and ubiquitous forms of pollution globally. The potential fate and effects of plastic pollution on birds is a rapidly growing area of research, but knowledge of terrestrial and freshwater species is limited. Birds of prey have been particularly understudied, with no published data on plastic ingestion in raptors in Canada to date, and very few studies globally. To assess the ingestion of plastic in raptors, we analysed the contents of the upper gastrointestinal tracts from a total of 234 individuals across 15 raptor species, collected between 2013 and 2021. Upper gastrointestinal tracts were assessed for plastics and anthropogenic particles > 2 mm in size. Of the 234 specimens examined, only five individuals across two species had evidence of retained anthropogenic particles in the upper gastrointestinal tract. Two of 33 bald eagles (Haliaeetus leucocephalus, 6.1%) had retained plastics in the gizzard, while three of 108 barred owls (Strix varia, 2.8%) had retained plastic and non-plastic anthropogenic litter. The remaining 13 species were negative for particles > 2 mm in size (N = 1-25). These results suggest that most hunting raptor species do not appear to ingest and retain larger anthropogenic particles, though foraging guild and habitat may influence risk. We recommend that future research investigate microplastic accumulation in raptors, in order to gain a more holistic understanding of plastic ingestion in these species. Future work should also focus on increasing sample sizes across all species to improve the ability to assess landscape- and species-level factors that influence vulnerability and susceptibility of plastic pollution ingestion.
Topics: Animals; British Columbia; Plastics; Raptors; Strigiformes; Eating; Environmental Monitoring
PubMed: 37243770
DOI: 10.1007/s11356-023-27830-4