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Journal of Hazardous Materials Jul 2023Polyethylene (PE) is the most widely used type of plastic food packaging, in which chemicals can potentially migrate into packaged foods. The implications of using and... (Review)
Review
Polyethylene (PE) is the most widely used type of plastic food packaging, in which chemicals can potentially migrate into packaged foods. The implications of using and recycling PE from a chemical perspective remain underexplored. This study is a systematic evidence map of 116 studies looking at the migration of food contact chemicals (FCCs) across the lifecycle of PE food packaging. It identified a total of 377 FCCs, of which 211 were detected to migrate from PE articles into food or food simulants at least once. These 211 FCCs were checked against the inventory FCCs databases and EU regulatory lists. Only 25% of the detected FCCs are authorized by EU regulation for the manufacture of food contact materials. Furthermore, a quarter of authorized FCCs exceeded the specific migration limit (SML) at least once, while one-third (53) of non-authorised FCCs exceeded the threshold value of 10 μg/kg. Overall, evidence on FCCs migration across the PE food packaging lifecycle is incomplete, especially at the reprocessing stage. Considering the EU's commitment to increase packaging recycling, a better understanding and monitoring of PE food packaging quality from a chemical perspective across the entire lifecycle will enable the transition towards a sustainable plastics value chain.
Topics: Polyethylene; Food Contamination; Plastics; Food Packaging; Food
PubMed: 37099905
DOI: 10.1016/j.jhazmat.2023.131422 -
Scientific Reports Aug 2022In times of collective concern about pandemics, body-shield resuscitation barrier devices are more and more considered to protect against transmission of different...
In times of collective concern about pandemics, body-shield resuscitation barrier devices are more and more considered to protect against transmission of different pathogens between rescuers and patients. The objective of this experimental study was to investigate the characteristics of blood drops dispersed on the surface of four different foils suitable for blanketing patients during resuscitation. We analyzed run-off characteristics of blood stains depending on surface properties of polyvinyl chloride, polyethylene, polyethylene terephthalate and aluminum-coated polyethylene terephthalate. Confocal fluorescence microscopy revealed less cellular density and lack of fibrin networks in blood stains on the four foil surfaces than on paper towel. Delayed clotting went along with larger areas of contamination indicating a greater likelihood of coming into contact with potential germs but a smaller chance of contracting an infection. Space blankets as obligatory components of first aid kits are readily available for rescuers and serve as a mechanical barrier between rescuers and patients during resuscitation.
Topics: Humans; Polyethylene; Polyethylene Terephthalates; Protective Devices; Resuscitation; Surface Properties
PubMed: 35945452
DOI: 10.1038/s41598-022-17915-4 -
European Journal of Pharmaceutical... May 2022When equilibrium of leaching is reached within a product's duty cycle, partition coefficients polymer/solution dictate the maximum accumulation of a leachable and thus,...
Linear solvation energy relationships (LSERs) for robust prediction of partition coefficients between low density polyethylene and water. Part I: Experimental partition coefficients and model calibration.
When equilibrium of leaching is reached within a product's duty cycle, partition coefficients polymer/solution dictate the maximum accumulation of a leachable and thus, patient exposure by leachables. Yet, in the pharmaceutical and food industry, exposure estimates based on predictive modeling typically rely on coarse estimations of the partition coefficient, with accurate and robust models lacking. This first part of the study aimed to investigate linear solvation energy relationships (LSERs) as high performing models for the prediction of partition coefficients polymer/water. For this, partition coefficients between low density polyethylene (LDPE) and aqueous buffers for 159 compounds spanning a wide range of chemical diversity, molecular weight, vapor pressure, aqueous solubility and polarity (hydrophobicity) were determined and complimentary data collected from the literature (n=159, MW: 32 to 722, logK: -0.72 to 8.61 and logK: -3.35 up to 8.36). The chemical space represented by this compounds set is considered indicative for the universe of compounds potentially leaching from plastics. Based on the dataset for the LDPE material purified by solvent extraction, a LSER model for partitioning between LDPE and water was calibrated to give:logK=-0.529+1.098E-1.557S-2.991A-4.617B+3.886V. The model was proven accurate and precise (n = 156, R = 0.991, RMSE = 0.264). Further, it was demonstrated superior over a log-linear model fitted to the same data. Nonetheless, it could be shown that log-linear correlations against logK can be of value for the estimation of partition coefficients for nonpolar compounds exhibiting low hydrogen-bonding donor and/or acceptor propensity. For nonpolar compounds, the log - linear model was found as: logK=1.18logK-1.33 (n = 115, R=0.985, RMSE=0.313). In contrast, with mono-/bipolar compounds included into the regression data set, an only weak correlation was observed (n= 156, R = 0.930, RMSE = 0.742) rendering the log-linear model of more limited value for polar compounds. Notably, sorption of polar compounds into pristine (non-purified) LDPE was found to be up to 0.3 log units lower than into purified LDPE. To identify maximum (i. e. worst-case) levels of leaching in support of chemical safety risk assessments on systems attaining equilibrium before end of shelf-life, it appears adequate to utilize LSER - calculated partition coefficients (in combination with solubility data) by ignoring any kinetical information.
Topics: Calibration; Humans; Hydrophobic and Hydrophilic Interactions; Polyethylene; Solubility; Water
PubMed: 35150822
DOI: 10.1016/j.ejps.2022.106137 -
PeerJ 2022Agricultural plastic mulches offer great benefits such as higher yields and lower pesticide use. Yet, plastic mulches may disintegrate over time and fragment into...
BACKGROUND
Agricultural plastic mulches offer great benefits such as higher yields and lower pesticide use. Yet, plastic mulches may disintegrate over time and fragment into smaller debris. Such plastic debris is expected to remain in the field after removal of the plastic mulch and thus contributes to soil contamination with plastics.
METHOD
To investigate this, we collected soil samples at 0-10 cm and 10-40 cm depth from three fields covered with black mulch film for three consecutive years. Three fields without any reported plastic use served as control. Visual plastic debris > 1 cm (macroplastics) was collected from the soil surface. Mesoplastics between 2 mm and 1 cm were density separated from the sampled soil using saturated NaCl solution and analyzed by Fourier-transform infrared spectroscopy. Debris ≤ 2 mm (microplastics) was dispersed from 50 g soil using sodium hexametaphosphate solution followed by the aforementioned density separation. The separated polyethylene (PE), polypropylene (PP), and polystyrene (PS) were quantified via solvent-based pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS).
RESULTS
With 89-206 fragments ha, the majority of macroplastics were located in fields previously covered with mulch films. 80% of the collected specimen were identified as black PE film. The number of mesoplastics in plastic-mulched soil was 2.3 particles kg, while only 1.0 particles kg were found in the reference fields. Py-GC/MS revealed microplastic levels of up to 13 mg kg. The PE content was significantly higher in plastic-mulched fields than in reference fields.
DISCUSSION
Although the identified plastic levels are lower than those reported in comparable studies, our results still suggest that plastic mulching functions as a source of plastic debris in agricultural systems. Due to its severely restricted degradability, these plastics are likely to accumulate in soil in the long term and further fragment into smaller and smaller debris.
Topics: Plastics; Soil; Microplastics; Agriculture; Polyethylene; Germany
PubMed: 35873916
DOI: 10.7717/peerj.13781 -
Waste Management & Research : the... Sep 2022This article describes the catalytic cracking of low-density polyethylene over attapulgite clay and iron substituted tungstophosphate/attapulgite clay...
This article describes the catalytic cracking of low-density polyethylene over attapulgite clay and iron substituted tungstophosphate/attapulgite clay (Fe-POM/attapulgite) composite materials to evaluate their suitability and performance for recycling of plastic waste into liquid fuel. The prepared catalysts enhanced the yield of liquid fuel (hydrocarbons) produced in cracking process. A maximum yield of 82% liquid oil fraction with a negligible amount of coke was obtained for 50% Fe-POM/attapulgite composite. Whereas, only 68% liquid oil fractions with a large amount of solid black residue was produced in case of non-catalytic pyrolysis. Moreover, Fe-POM/attapulgite clay composites showed higher selectivity towards lower hydrocarbons (C-C) with aliphatic hydrocarbons as major fractions. These synthesised composite catalysts significantly lowered the pyrolysis temperature from 375°C to 310°C. Hence, recovery of valuable fuel oil from polyethylene using these synthesised catalysts suggested their applicability for energy production from plastic waste at industrial level as well as for effective environment pollution control.
Topics: Catalysis; Clay; Hydrocarbons; Magnesium Compounds; Plastics; Polyethylene; Pyrolysis; Silicon Compounds
PubMed: 35243944
DOI: 10.1177/0734242X221080084 -
Current Biology : CB Aug 2017A number of previous studies have reported microbial degradation of polyethylene [1,2]. Fourier transform infrared spectroscopy analyses of the products of degradation...
A number of previous studies have reported microbial degradation of polyethylene [1,2]. Fourier transform infrared spectroscopy analyses of the products of degradation are, in many cases, contradictory, especially with regard to the relative intensities of different signals, suggesting that pathways are complex and may differ among organisms [1,2]. A detailed consideration of possible degradation products and pathways would have been beyond the scope of our initial brief report [3]. Nevertheless, the peaks to which we drew attention are consistent with those generally described in other studies.
Topics: Animals; Larva; Moths; Polyethylene; Spectroscopy, Fourier Transform Infrared
PubMed: 28787600
DOI: 10.1016/j.cub.2017.07.005 -
Marine Pollution Bulletin Jul 2023This study identified and quantified microplastics in the Bay of Asunción, Paraguay, and its main tributaries. Surface water samples were sieved in duplicate at six...
This study identified and quantified microplastics in the Bay of Asunción, Paraguay, and its main tributaries. Surface water samples were sieved in duplicate at six locations using stainless-steel sieves (0.3-4.75 mm range), digested employing the Fenton's reaction (Fe-catalysed HO digestion), and floated using NaCl and NaI. Particles were inspected using a microscope and characterized by IR spectrometry. Microplastics were found in all samples; more abundant (p < 0.05) in water from the bay (13.2 ± 13.4 items·m) than from the tributaries (1.0 ± 0.5 items·m). Most microplastics were common polymers and their abundance was in the order polypropylene > high-density polyethylene > low-density polyethylene, transparent and white. The results were similar to other regional studies and suggested that their main source was single-use packaging, disposed inadequately due to poor garbage collection.
Topics: Microplastics; Plastics; Water; Bays; Paraguay; Hydrogen Peroxide; Water Pollutants, Chemical; Environmental Monitoring; Polyethylene
PubMed: 37269701
DOI: 10.1016/j.marpolbul.2023.115075 -
International Journal of Environmental... Jan 2023Fomite transmission is a possible route by which different pathogens spread within facilities. In hospital settings, elevator buttons are widely observed to be covered...
Fomite transmission is a possible route by which different pathogens spread within facilities. In hospital settings, elevator buttons are widely observed to be covered with various types of plastic wraps; however, limited information is available concerning the impact of different plastic materials on cleaning. Our study aimed to identify which plastic material is suitable for the coverage of elevator buttons and the optimal intervals for their cleaning. We tested six plastic covers, including polyethylene (PE), polymethylpentene (PMP), polyvinyl chloride (PVD), and polyvinylidene chloride (PVDC) plastic wraps; a thermoplastic polyurethane (TPU) keyboard cover; and a polyethylene terephthalate-ethylene vinyl acetate (PET-EVA) laminating film, which are plastic films. The bioburden on the elevator buttons at different time intervals was measured using an adenosine triphosphate (ATP) bioluminescence assay. Our results show that wraps made of PVDC had superior durability compared with those of PMP, PVC, and PVDC, in addition to the lowest detectable ATP levels among the six tested materials. Regarding different button locations, the highest ATP values were found in door-close buttons followed by door-open, and first-floor buttons after one- and three-hour intervals (p = 0.024 and p < 0.001, respectively). After routine disinfection, the ATP levels of buttons rapidly increased after touching and became more prominent after three hours (p < 0.05). Our results indicate that PVDC plastic wraps have adequate durability and the lowest residual bioburden when applied as covers for elevator buttons. Door-close and -open buttons were the most frequently touched sites, requiring more accurate and precise disinfection; therefore, cleaning intervals of no longer than three hours may be warranted.
Topics: Disinfection; Elevators and Escalators; Polyethylene; Adenosine Triphosphate
PubMed: 36674403
DOI: 10.3390/ijerph20021649 -
Molecules (Basel, Switzerland) Feb 2021For many antibacterial polymer fibres, especially for those with natural functional additives, the antibacterial response might not last over time. Moreover, the...
For many antibacterial polymer fibres, especially for those with natural functional additives, the antibacterial response might not last over time. Moreover, the mechanical performance of polymeric fibres degrades significantly during the intended operation, such as usage in textile and industrial filter applications. The degradation process and overall ageing can lead to emitted volatile organic compounds (VOCs). This work focused on the usage of pine rosin as natural antibacterial chemical and analysed the weathering of melt-spun polyethylene (PE) and poly lactic acid (PLA) polyfilaments. A selected copolymer surfactant, as an additional chemical, was studied to better integrate rosin with the molecular structure of the plastics. The results reveal that a high 20 w-% of rosin content can be obtained by surfactant addition in non-oriented PE and PLA melt-spun polyfilaments. According to the VOC analysis, interestingly, the total emissions from the melt-spun PE and PLA fibres were lower for rosin-modified (10 w-%) fibres and when analysed below 60 ℃. The PE fibres of the polyfilaments were found to be clearly more durable in terms of the entire weathering study, i.e., five weeks of ultraviolet radiation, thermal ageing and standard washing. The antibacterial response against Gram-positive by the rosin-containing fibres was determined to be at the same level (decrease of 3-5 logs cfu/mL) as when using 1.0 w-% of commercial silver-containing antimicrobial. For the PE polyfilaments with rosin (10 w-%), full killing response (decrease of 3-5 logs cfu/mL) remained after four weeks of accelerated ageing at 60 ℃.
Topics: Anti-Bacterial Agents; Microbial Sensitivity Tests; Pinus; Plastics; Polyesters; Polyethylene; Polymers; Resins, Plant; Silver; Staphylococcus aureus; Textiles; Volatile Organic Compounds
PubMed: 33562272
DOI: 10.3390/molecules26040876 -
Molecules (Basel, Switzerland) Sep 2020The water-resistant characteristics of ultraviolet crosslinked polyethylene (UV-XLPE) are investigated specially for the dependence on the hydrophilicities of auxiliary...
The water-resistant characteristics of ultraviolet crosslinked polyethylene (UV-XLPE) are investigated specially for the dependence on the hydrophilicities of auxiliary crosslinkers, which is significant to develop high-voltage insulating cable materials. As auxiliary crosslinking agents of polyethylene, triallyl isocyanurate (TAIC), trimethylolpropane trimethacrylate (TMPTMA), and N,N'-m-phenylenedimaleimide (HAV2) are individually adopted to prepared XLPE materials with the UV-initiation crosslinking technique, for the study of water-tree resistance through the accelerating aging experiments with water blade electrode. The stress-strain characteristics and dynamic viscoelastic properties of UV-XLPE are tested by the electronic tension machine and dynamic thermomechanical analyzer. Monte Carlo molecular simulation is used to calculate the interaction parameters and mixing energy of crosslinker/water binary systems to analyze the compatibility between water and crosslinker molecules. Water-tree experiments verify that XLPE-TAIC represents the highest ability to inhibit the growth of water-trees, while XLPE-HAV2 shows the lowest resistance to water-trees. The stress-strain and viscoelastic properties show that the concentration of molecular chains connecting the adjacent lamellae in amorphous phase of XLPE-HAV2 is significantly higher than that of XLPE-TAIC and XLPE-TMPTMA. The molecular simulation results demonstrate that TAIC/water and TMPTMA/water binary systems possess a higher hydrophilicity than that of HAV2/water, as manifested by their lower interaction parameters and mixing free energies. The auxiliary crosslinkers can not only increase the molecular density of amorphous polyethylene between lamellae to inhibit water-tree growth, but also prevent water molecules at insulation defects from agglomerating into micro-water beads by increasing the hydrophilicity of auxiliary crosslinkers, which will evidently reduce the damage of micro-water beads on the amorphous phase in UV-XLPE. The better compatibility of TAIC and water molecules is the dominant reason accounting for the excellent water resistance of XLPE-TAIC.
Topics: Algorithms; Cross-Linking Reagents; Hydrophobic and Hydrophilic Interactions; Models, Theoretical; Molecular Structure; Monte Carlo Method; Polyethylene; Trees; Ultraviolet Rays; Water
PubMed: 32927806
DOI: 10.3390/molecules25184147