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Environmental Monitoring and Assessment Sep 2023Nanoplastics (plastic particles smaller than 1 μm) are the least-known type of marine litter. Nanoplastics (NPs) have attracted much interest in recent years because... (Review)
Review
Nanoplastics (plastic particles smaller than 1 μm) are the least-known type of marine litter. Nanoplastics (NPs) have attracted much interest in recent years because of their prevalence in the environment and the potential harm they can cause to living organisms. This article focuses on understanding NPs and their fate in the marine environment. Sources of NPs have been identified, including accidental release from products or through nano-fragmentation of larger plastic debris. As NPs have a high surface area, they may retain harmful compounds. The presence of harmful additives in NPs poses unique practical challenges for studies on their toxicity. In this review, several methods specifically adapted for the physical and chemical characterization of NPs have been discussed. Furthermore, the review provides an overview of the translocation and absorption of NPs into organisms, along with an evaluation of the release of potential toxins from NPs. Further, we have provided an overview about the existing methods suggested for the possible degradation of these NPs. We conclude that the hazards of NPs are plausible but unknown, necessitating a thorough examination of NPs' sources, fate, and effects to better mitigate and spread awareness about this emerging contaminant.
Topics: Microplastics; Environmental Monitoring; Plastics
PubMed: 37695547
DOI: 10.1007/s10661-023-11701-z -
Journal of Hazardous Materials Sep 2023Microplastics (MPs) are emerging pollutants. Landfills store up to 42% of worldwide plastic waste and serve as an important source of MPs. However, the study of MPs...
A landfill serves as a critical source of microplastic pollution and harbors diverse plastic biodegradation microbial species and enzymes: Study in large-scale landfills, China.
Microplastics (MPs) are emerging pollutants. Landfills store up to 42% of worldwide plastic waste and serve as an important source of MPs. However, the study of MPs distribution and the plastic biodegradation potential in landfills is limited. In this study, the distribution of abundance, size, morphology and polymer type of MPs and plastics biodegradation species in refuse samples along landfill depths were extensively investigated within a large-scale landfill in Shenzhen, China. In addition, plastics biodegradation enzymes were evaluated in seven Chinese large-scale landfills leachate. MPs distribution pattern was investigated in all refuse samples. The abundance of MPs in refuse samples varied between 81 and 133 items/g. The size of MPs in all samples varied between 0.03 and 5 mm, and the average sizes were 1.2 mm ± 0.1 mm. The main morphology and polymer type were fragments and cellophane, respectively. Landfill depth was significantly negatively correlated with the relative abundance of MPs size 1-5 mm (p < 0.05) and was positively correlated with the relative abundance of MPs size < 0.2 mm (p < 0.05), suggesting that plastics were broken down during municipal solid waste decomposition. The multiple regression on matrices analysis further showed the landfill depths and plastic morphology significantly impact the MPs distribution. The strains, Lysinibacillus massiliensis (with relative abundance of 1.8%) for low-density polyethylene and polystyrene biodegradation, and Pseudomonas stutzeri (0.1%) for low density polythene and polypropylene biodegradation, were detected on the plastic surface with high relative abundance. Furthermore, 75 plastic degradation species and their associated 31 enzymes (breakdown 24 plastics) were discovered in seven landfills leachate samples.
Topics: Plastics; Microplastics; Polyethylene; China; Water Pollutants, Chemical; Waste Disposal Facilities; Biodegradation, Environmental; Environmental Monitoring
PubMed: 37263024
DOI: 10.1016/j.jhazmat.2023.131676 -
Environmental Science & Technology Oct 2023It remains unknown whether plastic-biodegrading macroinvertebrates generate microplastics (MPs) and nanoplastics (NPs) during the biodegradation of plastics. In this...
Unveiling Fragmentation of Plastic Particles during Biodegradation of Polystyrene and Polyethylene Foams in Mealworms: Highly Sensitive Detection and Digestive Modeling Prediction.
It remains unknown whether plastic-biodegrading macroinvertebrates generate microplastics (MPs) and nanoplastics (NPs) during the biodegradation of plastics. In this study, we utilized highly sensitive particle analyzers and pyrolyzer-gas chromatography mass spectrometry (Py-GCMS) to investigate the possibility of generating MPs and NPs in frass during the biodegradation of polystyrene (PS) and low-density polyethylene (LDPE) foams by mealworms ( larvae). We also developed a digestive biofragmentation model to predict and unveil the fragmentation process of ingested plastics. The mealworms removed 77.3% of ingested PS and 71.1% of ingested PE over a 6-week test period. Biodegradation of both polymers was verified by the increase in the δC signature of residual plastics, changes in molecular weights, and the formation of new oxidative functional groups. MPs accumulated in the frass due to biofragmentation, with residual PS and PE exhibiting the maximum percentage by number at 2.75 and 7.27 μm, respectively. Nevertheless, NPs were not detected using a laser light scattering sizer with a detection limit of 10 nm and Py-GCMS analysis. The digestive biofragmentation model predicted that the ingested PS and PE were progressively size-reduced and rapidly biodegraded, indicating the shorter half-life the smaller plastic particles have. This study allayed concerns regarding the accumulation of NPs by plastic-degrading mealworms and provided critical insights into the factors controlling MP and NP generation during macroinvertebrate-mediated plastic biodegradation.
Topics: Animals; Polystyrenes; Polyethylene; Tenebrio; Plastics; Larva; Biodegradation, Environmental; Microplastics
PubMed: 37751481
DOI: 10.1021/acs.est.3c04406 -
Ying Yong Sheng Tai Xue Bao = the... Nov 2023Environmental endocrine disrupting chemicals (EDCs), known as environmental hormones, are exogenous chemicals that can disrupt hormone levels and cause dysfunction of... (Review)
Review
Environmental endocrine disrupting chemicals (EDCs), known as environmental hormones, are exogenous chemicals that can disrupt hormone levels and cause dysfunction of the secretory system in humans and animals. Plasticizers, which are widely used EDCs, are commonly used to enhance the flexibility of plastic products. As plastics age and wear, however, they can leach into the environment and enter the bodies of animals through various pathways such as the digestive tract and skin. They can lead to estrogen-like effects and have substantial reproductive toxicity. Residual plasticizer concentrations in the environment are typically low. Unlike high doses that induce acute damage to the reproductive system, low doses of plasticizers do not cause macroscopic harm and thus its reproductive toxicity is often overlooked for extended periods. An increasing number of studies conducted on humans and mice in recent years have demonstrated that low doses of plasticizers can induce reproductive toxicity by interfering with maternal behavior. Prenatal exposure to plasticizers can result in abnormal postnatal maternal behavior. Female offspring also exhibit significantly low maternal care, lactation, and other behaviors in adulthood, which may persist for multiple generations, significantly disrupting the animal breeding process and impacting the health and well-being of newborn pups. The underlying mechanisms have not been systematically summarized. The risk of continuous exposure to low-dose plasticizers in humans and animals has increased due to the extensive utilization of plastic and rubber products in modern production and lifestyle patterns. It is thus crucial to conduct a systematic review on the effects of low-dose plasticizers on maternal behavior. We reviewed the research progress on the disruptive effects of plasticizers on animals' maternal behavior and concluded that these effects are primarily caused by inducing oxidative stress damage and DNA methylation reprogramming in the hypothalamic-pituitary-ovarian axis, as well as disrupting the balance of the thyroid system and causing intestinal microbial disorders. It would offer a novel perspective for future studies about the influence of plasticizers and other environmental hormones on maternal behavior in domesticated animals.
Topics: Animals; Female; Humans; Mice; Pregnancy; Hormones; Maternal Behavior; Plasticizers; Plastics; Reproduction
PubMed: 37997427
DOI: 10.13287/j.1001-9332.202311.028 -
Environmental Science & Technology Aug 2023Plastic recycling and reprocessing activities may release organophosphate ester (OPE) flame retardants and plasticizers into the surrounding environment. However, the...
Nontarget Identification of Novel Organophosphorus Flame Retardants and Plasticizers in Rainfall Runoffs and Agricultural Soils around a Plastic Recycling Industrial Park.
Plastic recycling and reprocessing activities may release organophosphate ester (OPE) flame retardants and plasticizers into the surrounding environment. However, the relevant contamination profiles and impacts remain not well studied. This study investigated the occurrence of 28 OPEs and their metabolites (mOPEs) in rainfall runoffs and agricultural soils around one of the largest plastic recycling industrial parks in North China and identified novel organophosphorus compounds (NOPs) using high-resolution mass spectrometry-based nontarget analysis. Twenty and twenty-seven OPEs were detected in runoff water and soil samples, with total concentrations of 86.0-2491 ng/L and 2.53-199 ng/g dw, respectively. Thirteen NOPs were identified, of which eight were reported in the environment for the first time, including a chlorine-containing OPE, an organophosphorus heterocycle, a phosphite, three novel OPE metabolites, and two oligomers. Triphenylphosphine oxide and diphenylphosphinic acid occurred ubiquitously in runoffs and soils, with concentrations up to 390 ng/L and 40.2 ng/g dw, respectively. The downwind areas of the industrial park showed elevated levels of OPEs and NOPs. The contribution of hydroxylated mOPEs was higher in soils than in runoffs. These findings suggest that plastic recycling and reprocessing activities are significant sources of OPEs and NOPs and that biotransformation may further increase the ecological and human exposure risk.
Topics: Humans; Plasticizers; Plastics; Organophosphorus Compounds; Flame Retardants; Soil; Organophosphates; China; Esters; Environmental Monitoring
PubMed: 37579047
DOI: 10.1021/acs.est.3c02156 -
The Science of the Total Environment Nov 2023Constantly raising microplastic (MP) contamination of water sources poses a direct threat to the gentle balance of the marine environment. This study focuses on a...
Constantly raising microplastic (MP) contamination of water sources poses a direct threat to the gentle balance of the marine environment. This study focuses on a multifactor hazard evaluation of conventional (polyethylene - PE, polypropylene - PP, and polystyrene - PS) and alternative (polyethylene terephthalate with 25 % or 50 % recycled material and polylactic acid) plastics. The risk assessment framework explored included MP abundance, water acidification potential, surface oxidation, fragmentation, and bacterial growth inhibition. Based on MP monitoring campaigns worldwide, we conclude that PE-based plastics are the most abundant MPs in water samples (comprise up to 82 % the MP in those samples). A year-long weathering experiment showed that PS-based and PP-based plastics were oxidized to a higher extent, resulting in the highest water acidification with pH reduction of up to three orders of magnitude. Finally, our laboratory experiments showed that weathered PS was the most fragile plastic during mechanical degradation, while both PP- and PS-based plastic extracts showed a significant growth inhibition toward the marine microorganisms (Bacillus sp. and Pseudoaltermonas sp). Using the examined factors as weighted inputs into our framework, this holistic evaluation of hazards suggest that PP-based plastic products were the most hazardous compared to the other conventional and alternative plastic types.
Topics: Microplastics; Plastics; Water Pollutants, Chemical; Polystyrenes; Polyethylene; Water; Environmental Monitoring
PubMed: 37607638
DOI: 10.1016/j.scitotenv.2023.166459 -
Environmental Research Nov 2023Exposure to phthalates, adipates, bisphenol-A (BPA), and pesticides may have important health consequences for children, but little is known regarding their presence in...
BACKGROUND
Exposure to phthalates, adipates, bisphenol-A (BPA), and pesticides may have important health consequences for children, but little is known regarding their presence in school meals, a major food source for children. The aims of this study were to determine the presence of phthalates, adipates, BPA, and pesticides in school meals.
METHODS
Using a cross-sectional design, n = 50 school meal components were collected from four school districts in New England (n = 8 elementary/K-8 schools) differing preparation methods (on-site scratch cooking and pre-packaged heat and serve meals with plastic films) between 2019 and 2021. Meal components were tested for the presence of phthalates, adipates, BPA, and pesticides by an independent laboratory.
RESULTS
One adipate, DEHA, was detected in 42% of samples (range 0.08 mg/kg - 50.39 mg/kg). Among the prepackaged foods, DEHA was detected in 86% of samples, which also contained the highest average concentrations among all the samples tested. The phthalate Diisononyl phthalate (DINP) was detected in only one sample, and BPA was not detected in any of the samples tested. Pesticides were detected in 64% of produce and 27% of entrées, but most had levels that were lower than the average levels detected by the USDA's Pesticide Data Program and only one sample had levels that exceeded those detected by the USDA (Cyfluthrin levels in one sample of apples were 0.038 mg/kg compared with an USDA average range of 0.004-0.032 mg/kg).
CONCLUSIONS
Overall pesticides and phthalate levels in school meals are low and BPA was not detected. However, this study suggests that manufacturers may be changing to less studied plasticizers such as DEHA. More studies should examine the impact of DEHA on human health, particularly among children. As schools transition back from the COVID-19 pandemic, foods packaged in plastic should be minimized where possible. Overall, school meals remain one of the healthiest options for children and policies that support on site cooking can further strengthen the quality of school meals.
Topics: Child; Humans; Pesticides; Cross-Sectional Studies; Pandemics; COVID-19; Phthalic Acids; Plasticizers; Adipates; Meals
PubMed: 37442262
DOI: 10.1016/j.envres.2023.116632 -
Environmental Science and Pollution... Feb 2024Increasing pollution of plastic waste is one of the major global environmental threats, deteriorating our land, water and air. The shift towards biobased, biodegradable... (Review)
Review
Increasing pollution of plastic waste is one of the major global environmental threats, deteriorating our land, water and air. The shift towards biobased, biodegradable and compostable plastics is considered a green alternative to petroleum-based plastic due to its renewable source or biodegradability. However, there is a misconception about biodegradable plastics and their degradability and behaviour after service life. Biobased, biodegradable and compostable plastics offer various benefits such as less carbon footprint, energy efficiency, independence and eco-safety. On the other hand, there are some disadvantages such as higher cost, limited recycling, misuse of terms and lack of legislation. Also, there is an urgent need for comparable international standard methods to define these materials as biodegradable material, or biocompostable material. There are some standards currently available, however, an in-depth detail and explanation of these standards is still missing. This review outlines the basic definition and chemical structure of biobased, biodegradable and compostable plastics; describes the degradation pathways of biodegradable and compostable plastics; and summarises current key applications of these materials together with possible future applications in different industries. Finally, strategies are developed for minimising the environmental impacts and the need for future research is proposed.
Topics: Biodegradable Plastics; Recycling; Biodegradation, Environmental; Industry; Carbon Footprint; Plastics
PubMed: 38177642
DOI: 10.1007/s11356-023-31689-w -
Environmental Science & Technology Jan 2024Hazardous chemicals in building and construction plastics can lead to health risks due to indoor exposure and may contaminate recycled materials. We systematically...
Hazardous chemicals in building and construction plastics can lead to health risks due to indoor exposure and may contaminate recycled materials. We systematically sampled new polyvinyl chloride floorings on the Swiss market ( = 151). We performed elemental analysis by X-ray fluorescence, targeted and suspect gas chromatography-mass spectrometry analysis of -phthalates and alternative plasticizers, and bioassay tests for cytotoxicity and oxidative stress, and endocrine, mutagenic, and genotoxic activities (for selected samples). Surprisingly, 16% of the samples contained regulated chemicals above 0.1 wt %, mainly lead and bis(2-ethylhexyl) phthalate (DEHP). Their presence is likely related to the use of recycled PVC in new flooring, highlighting that uncontrolled recycling can delay the phase-out of hazardous chemicals. Besides DEHP, 29% of the samples contained other -phthalates (mainly diisononyl and diisodecyl phthalates, DiNP and DiDP) above 0.1 wt %, and 17% of the samples indicated a potential to cause biological effects. Considering some overlap between these groups, they together make up an additional 35% of the samples of potential concern. Moreover, both suspect screening and bioassay results indicate the presence of additional potentially hazardous substances. Overall, our study highlights the urgent need to accelerate the phase-out of hazardous substances, increase the transparency of chemical compositions in plastics to protect human and ecosystem health, and enable the transition to a safe and sustainable circular economy.
Topics: Humans; Plasticizers; Diethylhexyl Phthalate; Ecosystem; Phthalic Acids; Plastics; Hazardous Substances
PubMed: 38241221
DOI: 10.1021/acs.est.3c04851 -
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