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International Journal of Molecular... May 2022The global utilization of single-use, non-biodegradable plastics, such as bottles made of polyethylene terephthalate (PET), has contributed to catastrophic levels of...
Microbial Consortia and Mixed Plastic Waste: Pangenomic Analysis Reveals Potential for Degradation of Multiple Plastic Types via Previously Identified PET Degrading Bacteria.
The global utilization of single-use, non-biodegradable plastics, such as bottles made of polyethylene terephthalate (PET), has contributed to catastrophic levels of plastic pollution. Fortunately, microbial communities are adapting to assimilate plastic waste. Previously, our work showed a full consortium of five bacteria capable of synergistically degrading PET. Using omics approaches, we identified the key genes implicated in PET degradation within the consortium's pangenome and transcriptome. This analysis led to the discovery of a novel PETase, EstB, which has been observed to hydrolyze the oligomer BHET and the polymer PET. Besides the genes implicated in PET degradation, many other biodegradation genes were discovered. Over 200 plastic and plasticizer degradation-related genes were discovered through the Plastic Microbial Biodegradation Database (PMBD). Diverse carbon source utilization was observed by a microbial community-based assay, which, paired with an abundant number of plastic- and plasticizer-degrading enzymes, indicates a promising possibility for mixed plastic degradation. Using RNAseq differential analysis, several genes were predicted to be involved in PET degradation, including aldehyde dehydrogenases and several classes of hydrolases. Active transcription of PET monomer metabolism was also observed, including the generation of polyhydroxyalkanoate (PHA)/polyhydroxybutyrate (PHB) biopolymers. These results present an exciting opportunity for the bio-recycling of mixed plastic waste with upcycling potential.
Topics: Bacteria; Microbial Consortia; Plasticizers; Plastics; Polyethylene Terephthalates
PubMed: 35628419
DOI: 10.3390/ijms23105612 -
Archivum Immunologiae Et Therapiae... Jun 2018Di(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer, mainly serves as an additive to render polyvinyl chloride (PVC) soft and flexible. PVC plastics have become... (Review)
Review
Di(2-ethylhexyl)phthalate (DEHP), a widely used plasticizer, mainly serves as an additive to render polyvinyl chloride (PVC) soft and flexible. PVC plastics have become ubiquitous in our modern society. Yet, the leaching of DEHP from PVC-based consumables ultimately results in the deposition in certain tissues via inadvertent applications. Health risks for human populations exposed to DEHP has been assumed by studies on rodents and other species, including the DEHP-induced developmental dysregulation, reproductive impairments, tumorigenesis, and diseases in a transgenerational manner. In this review, we comprehensively summarize the accumulated literature regarding the multifaceted roles of DEHP in the activation of the nuclear receptors, the alteration of the redox homeostasis, epigenetic modifications and the acquisition of chemoresistance.
Topics: Animals; Antineoplastic Agents; Carcinogenesis; Diethylhexyl Phthalate; Drug Resistance, Neoplasm; Epigenesis, Genetic; Gene Expression Regulation, Neoplastic; Homeostasis; Humans; Neoplasms; Oxidation-Reduction; Phthalic Acids; Plasticizers; Polyvinyl Chloride; Receptors, Cytoplasmic and Nuclear
PubMed: 29209738
DOI: 10.1007/s00005-017-0494-2 -
Molecules (Basel, Switzerland) Jan 2022While bio-based but chemically synthesized polymers such as polylactic acid require industrial conditions for biodegradation, protein-based materials are home... (Review)
Review
While bio-based but chemically synthesized polymers such as polylactic acid require industrial conditions for biodegradation, protein-based materials are home compostable and show high potential for disposable products that are not collected. However, so far, such materials lack in their mechanical properties to reach the requirements for, e.g., packaging applications. Relevant measures for such a modification of protein-based materials are plasticization and cross-linking; the former increasing the elasticity and the latter the tensile strength of the polymer matrix. The assessment shows that compared to other polymers, the major bottleneck of proteins is their complex structure, which can, if developed accordingly, be used to design materials with desired functional properties. Chemicals can act as cross-linkers but require controlled reaction conditions. Physical methods such as heat curing and radiation show higher effectiveness but are not easy to control and can even damage the polymer backbone. Concerning plasticization, effectiveness and compatibility follow opposite trends due to weak interactions between the plasticizer and the protein. Internal plasticization by covalent bonding surpasses these limitations but requires further research specific for each protein. In addition, synergistic approaches, where different plasticization/cross-linking methods are combined, have shown high potential and emphasize the complexity in the design of the polymer matrix.
Topics: Biocompatible Materials; Cross-Linking Reagents; Enzymes; Hot Temperature; Mechanical Phenomena; Plasticizers; Proteins
PubMed: 35056758
DOI: 10.3390/molecules27020446 -
Food and Chemical Toxicology : An... Jun 2022Several non-ortho phthalate plasticizers, including ATBC, DEHA, DINCH, DOTP, and ESBO, are currently used in flexible PVC applications for food packaging and processing.... (Review)
Review
Several non-ortho phthalate plasticizers, including ATBC, DEHA, DINCH, DOTP, and ESBO, are currently used in flexible PVC applications for food packaging and processing. The aim of this review is to summarize the available toxicity, migration, and human biomonitoring data. Available assessments from US CPSC, EFSA, other governmental and non-governmental organizations, and published toxicology studies were used to show that these plasticizers are generally well-studied and demonstrate low toxicity with a focus on potential carcinogenicity, reproductive, developmental, and endocrine related adverse effects as well as biodegradation, aquatic toxicity, and bioaccumulation. Seven other plasticizers, 2EHESBO, ASE, COMGHA, DBT, DEHCH, PETV, and TOTM, have at least some recent but limited food contact clearances; assessments from CPSC, EFSA, and robust summaries in the REACH dossiers were reviewed for these products. Data gaps were found for some of these; however, there were no concerns raised by the existing data, and they for now have limited use in food contact applications. Migration of ASE, COMGHA, DINCH, DOTP, DEHCH, and TOTM in simulants for aqueous and low alcohol foods ranged from <0.02 to 0.165 mg/kg, which showed they are below established migration limits and well-suited for these applications. Human biomonitoring data are available for DINCH, DOTP, DEHA, DINA, and TOTM, and are essential for determining exposure from all uses.
Topics: Biological Monitoring; Food Packaging; Humans; Phthalic Acids; Plasticizers
PubMed: 35452769
DOI: 10.1016/j.fct.2022.112984 -
Cardiovascular Toxicology Dec 2014The ubiquitous nature of plastics has raised concerns pertaining to continuous exposure to plastic polymers and human health risks. Of particular concern is the use of... (Review)
Review
The ubiquitous nature of plastics has raised concerns pertaining to continuous exposure to plastic polymers and human health risks. Of particular concern is the use of endocrine-disrupting chemicals in plastic production, including di(2-ethylhexyl)phthalate (DEHP) and bisphenol A (BPA). Widespread and continuous exposure to DEHP and BPA occurs through dietary intake, inhalation, dermal and intravenous exposure via consumer products and medical devices. This article reviews the literature examining the relationship between DEHP and BPA exposure and cardiac toxicity. In vitro and in vivo experimental reports are outlined, as well as epidemiological studies which examine the association between these chemicals and cardiovascular outcomes. Gaps in our current knowledge are also discussed, along with future investigative endeavors that may help resolve whether DEHP and/or BPA exposure has a negative impact on cardiovascular physiology.
Topics: Benzhydryl Compounds; Cardiotoxicity; Child; Child, Preschool; Diethylhexyl Phthalate; Endocrine Disruptors; Environmental Exposure; Estrogens, Non-Steroidal; Humans; Infant; Infant, Newborn; Phenols; Plasticizers; Plastics
PubMed: 24811950
DOI: 10.1007/s12012-014-9258-y -
Environmental Health and Preventive... Jul 2019The plasticizer di(2-ethylhexyl) phthalate (DEHP) has been widely used in the manufacture of polyvinyl chloride-containing products such as medical and consumer goods.... (Review)
Review
The plasticizer di(2-ethylhexyl) phthalate (DEHP) has been widely used in the manufacture of polyvinyl chloride-containing products such as medical and consumer goods. Humans can easily be exposed to it because DEHP is ubiquitous in the environment. Recent research on the adverse effects of DEHP has focused on reproductive and developmental toxicity in rodents and/or humans. DEHP is a representative of the peroxisome proliferators. Therefore, peroxisome proliferator-activated receptor alpha (PPARα)-dependent pathways are the expected mode of action of several kinds of DEHP-induced toxicities. In this review, we summarize DEHP kinetics and its mechanisms of carcinogenicity and reproductive and developmental toxicity in relation to PPARα. Additionally, we give an overview of the impacts of science policy on exposure sources.
Topics: Animals; Diethylhexyl Phthalate; Environmental Pollutants; Haplorhini; Humans; Mice; PPAR alpha; Plasticizers; Rats
PubMed: 31279339
DOI: 10.1186/s12199-019-0802-z -
Current Environmental Health Reports Dec 2019Organophosphate esters (OPEs) are applied to a variety of consumer products, primarily as flame retardants and plasticizers. OPEs can leach out of products over time and... (Review)
Review
PURPOSE OF REVIEW
Organophosphate esters (OPEs) are applied to a variety of consumer products, primarily as flame retardants and plasticizers. OPEs can leach out of products over time and are consequently prevalent in the environment and frequently detected in human biomonitoring studies. Exposure during pregnancy is of particular concern as OPEs have recently been detected in placental tissues, suggesting they may be transferred to the developing infant. Also, studies have now shown that children typically experience higher exposure to several OPEs compared with adults, indicating they may be disproportionately impacted by these compounds. This review summarizes the current literature on reproductive and child health outcomes of OPE exposures and highlights areas for future research.
RECENT FINDINGS
Experimental animal studies demonstrate potential for OPEs to adversely impact health, and a limited number of epidemiologic studies conducted in adult cohorts suggest that OPEs may interfere with the endocrine system. Neurodevelopment is perhaps the most well studied of children's health endpoints, and several studies indicate that prenatal and early life OPE exposures impact both cognitive and behavioral development. Associations have also been reported with reproductive outcomes (e.g., fertilization and pregnancy loss) and with the timing of parturition and preterm birth. Cross-sectional studies also demonstrate associations between OPEs and respiratory health outcomes, allergic disease, and measures of adiposity. An expanding body of research demonstrates that OPEs are associated with adverse reproductive health and birth outcomes, asthma and allergic disease, early growth and adiposity, and neurodevelopment. Still, additional research is urgently needed to elucidate the full impact of OPEs on children's health.
Topics: Adult; Child; Cross-Sectional Studies; Environmental Exposure; Environmental Monitoring; Esters; Female; Flame Retardants; Humans; Maternal Exposure; Organophosphates; Plasticizers; Pregnancy; Prenatal Exposure Delayed Effects
PubMed: 31755035
DOI: 10.1007/s40572-019-00258-0 -
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 -
Advances in Clinical and Experimental... Jul 2017Tissue conditioners (TCs) are short-term soft liners, formed in situ from a mixture of a polymer powder and a liquid plasticizer. This article reviews the recent... (Review)
Review
Tissue conditioners (TCs) are short-term soft liners, formed in situ from a mixture of a polymer powder and a liquid plasticizer. This article reviews the recent advances in the composition, functions, clinical use, gelation process, and physical properties of TCs and their effects on denture bases and oral mucosa. TCs are used to improve the fit and function of an ill-fitting denture. They can also be used to treat abused mucosal tissues underlying ill-fitting acrylic dentures as temporary expedients. TCs are recommended as provisional liners to maintain the fit of removable dentures and to prevent mechanical irritation from the denture. TCs may also be used to rehabilitate cancer patients. The polymer powder, used in the formulation of TCs generally consists of polyethyl methacrylate (PEMA) and the liquid plasticizer is ester-based in ethyl alcohol solution without an acrylic monomer. The plasticizers are low molecular weight aromatic esters. Mixing of the powder and liquid results in polymer chain entanglement and the formation of a coherent gel characterized by viscoelastic behavior appropriate to its intended clinical use. The loss of surface integrity and surface roughness of TCs are regarded as the main problems in the denture bearing oral mucosa conditions resulting in inflammation of oral mucosa of the denture-bearing area - denture stomatitis. TCs provide an even distribution of masticatory force, accurately modeling itself to the changes which occur during the healing of lesion of substrate and can act therapeutically by incorporating antifungal or antibacterial agents.
Topics: Denture Bases; Denture Liners; Humans; Methylmethacrylates; Plasticizers
PubMed: 28691420
DOI: 10.17219/acem/62634 -
Environmental Research Oct 2022Sea turtles are particularly vulnerable to plastic exposures, and the associated chemical additives, due to their feeding strategies. The species Caretta caretta is a...
Sea turtles are particularly vulnerable to plastic exposures, and the associated chemical additives, due to their feeding strategies. The species Caretta caretta is a proposed sentinel of plastic pollution worldwide. Thus, there is a need to find adequate biomarkers of plastic exposure through non-invasive protocols for this IUCN protected species. Plasmatic acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and carboxylesterase (CE) which participate in xenobiotic and endogenous metabolic reactions could all serve as biomarkers, as they are responsive to plasticizers and have already proved adequate for identifying organophosphorus esters exposures. Here we measured plasmatic B-esterases in wild specimens captured as accidental by-catch. Measurements were taken in each individual either at entry into the rehabilitation program or immediately before release after a recovery period. For CE measurements, 4 commercial substrates were used as potentially indicative of distinct enzyme isoforms. Increased activity was seen with the butyrate-derived substrates. Plasmatic CE activities were over one order of magnitude higher than AChE and BuChE substrates. Moreover, an in vitro protocol with the inclusion of plastic additives such as tetrabromobisphenol A (TBBPA), bisphenol A and some of its analogues was considered a proxy of enzymatic interactions. A clear inhibition by TBBPA was found when using commercially purified AChE and recombinant CE proteins. Overall, from in vitro and in vivo evidences, CEs in plasma are sensitive and easily measurable and have been shown to significantly increase after turtles have been rehabilitated in rescue centres. Nevertheless, the inclusion of plastic (or plasticizers) characterisation would help to confirm its association with plasmatic enzyme modifications before they can be adopted as biomarkers of plastic contamination.
Topics: Acetylcholinesterase; Animals; Biomarkers; Butyrylcholinesterase; Esterases; Plasticizers; Plastics; Turtles; Water Pollutants
PubMed: 35688215
DOI: 10.1016/j.envres.2022.113639