Release Of Microplastics Research Articles

Washing machine filters to mitigate microplastics release: Citizen science study to estimate microfibers capture potential and assess their social acceptability

The accumulation of microplastics in the environment, particularly due to the significant contribution of synthetic clothing washing water, leads to a need for developing source-based retention solutions. The project's objective is to assess the capability of washing machine filters to capture microfibers from domestic wastewater under real laundry conditions. This involves developing a protocol for quantifying microfibers tailored to washing machine lint samples, estimating the potential microfiber capture by washing machine filters, and evaluating the social acceptability of using such filters in households. Volunteers were recruited and they used their washing machines normally, collecting lint in the filter over a 6-month period and documenting information for each load. Various reagents were tested using plastic controls and lint samples to select the most efficient one for removing organic matter without affecting microplastics. Microscopic visual alterations, chemical signatures via FTIR, and the efficacy of the digestion protocol were assessed through mass balance and visual counting. After discarding digestion protocols affecting plastic integrity, those ensuring the most efficient mass loss of organic matter were identified as H2O2 30 % for 5 days at room temperature (RT), NaOCl 3 % for 24 h at RT, and H2O2 30 % at 40 °C for 24 h. Polyester, acrylic, and polyamide controls were tested with NaOCl 3 % for 24 h and H2O2 30 % for 5 days, showing no changes in SEM images. The FTIR successfully recognized the chemical signature. More significant alterations on positive samples (cotton and cellulose) were observed after NaOCl exposure. The mean mass of microfibers remaining after digestion was estimated at 4.62 mg per liter of washing water or 61 mg/kg of washed garment. The survey revealed that 67.8 % of volunteer participants found the filter installation challenging, and 21.4 % had to hire a plumber, highlighting potential challenges associated with implementing washing machine filters on a large scale.

Exploring polystyrene weathering behavior: From surface traits to micro(nano)plastics and additives release

Plastic weathering in the natural environment is a dynamic and complex process, where the release of microplastics, nanoplastics and additives poses potential threats to ecosystems. Understanding the release of different weathering products from plastics is crucial for predicting and assessing the environmental hazards of plastics. This study systematically explored these phenomena by exposing polystyrene (PS) to UV irradiation and mechanical agitation for different durations (1 day, 5 days, 10 days, 20 days). The degree of aging, yellowing, brittleness, and the abundance of carbonyl (CO) functional groups in PS were all gradually increasing over time. The weathering pattern of PS surfaces manifested as initial particle oxidation followed by later cracks or flakes formation. The release of products was positively correlated with the aging degree of plastics, as well as among the various released products. Laser infrared and Raman tests indicated that, for microplastics, the size range of 10–20 μm consistently dominated over time, while the primary size range of nanoplastics shifted towards smaller sizes. Additives and other soluble products were prone to release from weathering plastics, with 20 different chemicals detected after 20 d. The release of plastic additives was closely related to aging time, additive type, and quantity. This study contributes to our understanding of the weathering process of plastics, clarifies the release patterns of products over time, and the relationships among different products. It helps predict and assess the environmental pollution caused by plastics.

Intraoral ageing of aligners and attachments: Adverse effects on clinical efficiency and release of biologically-active compounds.

The clinical application of aligners is accompanied by the ageing of the polymer appliances and the attachments used, which may result in inefficiency in reaching the predicted range of tooth movement, and release of compounds and microplastics in the oral cavity as a result of the friction, wear and attrition of the aligner and composite attachment. The purpose of this review is to present the mechanism and effects of in vivo ageing; describe the hydrolytic degradation of aligners and enzymatic degradation of composite attachments; examine the ageing pattern of aligners in vivo, under actual clinical scenarios; and identify a link to the discrepancy between predicted and actual clinical outcome. Lastly, strategies to deal with three potentially critical issues associated with the use of aligners, namely the necessity of weekly renewal, the dissimilar mechanical properties of aligner and attachment resulting in wear and plastic deformation of the aligner, and the development of integuments and biofilms with microbial colonization of the appliance, are discussed.

Screening the release of chemicals and microplastic particles from diverse plastic consumer products into water under accelerated UV weathering conditions

Photodegradation of plastic consumer products is known to accelerate weathering and facilitate the release of chemicals and plastic particles into the aquatic environment. However, these processes are complex. In our presented pilot study, eight plastic consumer products were leached in distilled water under strong ultraviolet (UV) light simulating eight months of Central European climate and compared to their respective dark controls (DCs). The leachates and formed plastic particles were exploratorily characterized using a range of chemical analytical tools to describe degradation and leaching processes. These techniques covered (a) microplastic analysis, showing substantial liberation of plastic particles further increased under UV exposure, (b) non-targeted mass spectrometric characterization of the leachates, revealing several hundreds of chemical features with typically only minor agreement between the UV exposure and the corresponding DCs, (c) target analysis of 71 organic analytes, of which 15 could be detected in at least one sample, and (d) metal(loid) analysis, which revealed substantial release of toxic metal(loid)s further enhanced under UV exposure. A data comparison with the US-EPA’s ToxVal and ToxCast databases showed that the detected metals and organic additives might pose substantial health and environmental concerns, requiring further study and comprehensive impact assessments.

Joint effect of black carbon deriving from wheat straw burning and plastic mulch film debris on the soil biochemical properties, bacterial and fungal communities

Black carbon (BC) formed after straw burning remains in farmland soil and coexists with plastic mulch film (PMF) debris. It is unclear how BC influences soil multifunctionality in the presence of PMF debris. In this study, we determined the joint effects of BC and PMF debris on soil biochemical properties and microbial communities. We conducted a soil microcosm experiment by adding BC formed by direct burning of wheat straw and PMF debris (polyethylene (PE) and biodegradable PMF (BP)) into soil at the dosages of 1 %, and soils were sampled on the 15th, 30th, and 100th day of soil incubation for high-throughput sequencing. The results showed that the degradation of PMF debris was accompanied by the release of microplastics (MPs). BC decreased NH4+-N (PE: 68.63 %; BP: 58.97 %) and NO3−-N (PE: 12.83 %; BP: 51.37 %) and increased available phosphorus (AP) (PE: 79.12 %; BP: 26.09 %) in soil containing PMF debris. There were significant differences in enzyme activity among all the treatments. High-throughput sequencing indicated that BC reduced bacterial and fungal richness and fungal diversity in PMF debris-exposed soil, whereas PMF debris and BC resulted in significant changes in the proportion of dominant phyla and genera of bacteria and fungi, which were affected by incubation time. Furthermore, BC affected microorganisms by influencing soil properties, and pH and N content were the main influencing factors. In addition, FAPRPTAX analysis indicated that BC and PMF debris affected soil C and N cycling. These findings provide new insights into the response of soil multifunctionality to BC and PMF debris.

Characteristics and aging of microplastics in waste activated sludge under persulfate and hydrothermal co-treatment: Impact of solid content and temperature

Activated persulfate and hydrothermal treatment (HTT) are often employed to treat waste activated sludge, which can improve the efficiency of subsequent sludge treatment and change the distribution of pollutants in the sludge. However, the impact of sludge solid content and temperature on the occurrence and aging of microplastics (MPs) during HTT remains poorly understood. This study investigated the effects of persulfate-HTT (SPS-HTT) co-treatment on the migration, occurrence, and aging of MPs in sludge with different solid contents (2% and 5% solid content). The results indicated that SPS-HTT co-treatment triggers both the disruption of sludge flocs and the melting deformation of MPs at high temperatures, leading to variations in the increasing trend of MP concentration in the solid-liquid phase at different solid contents. 5% solid content sludge showed a weak release of MPs from the solid phase. The proportion of fiber MPs first increased and then decreased with increasing temperature, while no significant changes were observed in the color and type of MPs. Higher temperature and solid content induced the melting deformation of MPs, exacerbated the aging of polypropylene MPs, and resulted in rough surfaces, higher carbonyl index, and variations in crystallinity. Moreover, the correlation between the carbonyl index and aging indicators increased with increasing solid content. The MP-derived dissolved organic matter under HTT primarily comprised soluble microbial by-products and humic acid-like substances. These findings underscore the significance of sludge solid content in affecting the migration and aging of MPs during HTT, and offer novel insights into the application of HTT to MP management in sludge treatment.

Release Characteristics of Small-Sized Microplastics in Bottled Drinks Using Flow Cytometry Sorting and Nile Red Staining

Small-sized microplastics (MPs) pose concerns about potential risks to both the environment and human health. However, research on MP pollution is hampered by limitations in the detection techniques. Also, few studies have provided insight into the release of small-sized MPs from disposable polyethylene terephthalate (PET)-bottled drinks for outdoor usage. Thus, PET bottles’ potential to release small MPs sized 1–100 μm outdoors was studied in relation to physical and chemical parameters (temperature, sunlight irradiation, and drink characteristics) using flow cytometry and Nile Red dye. The results showed that temperatures below 80 °C had little effect on the release of MPs from PET bottles. Sunlight irradiation and alkalinity were prone to promote the generation of MPs, mostly 1–5 μm in size. Moreover, the combined impact test implied that two pairings—acidity with temperature and alkalinity with sunlight—positively affected MP release, with maximum releases of 21,622 ± 2477 particles/L and 31,081 ± 7173 particles/L, respectively. Based on the rapid quantification of small-sized MPs using flow cytometry after Nile Red selection, the results hereby presented will assist researchers in reducing MP release and aid them in the evaluation of MPs’ contamination of aquatic environments.

Investigating the release of microplastics from tea bags into tea drinks and human exposure assessment

Investigating the release of microplastics from tea bags into tea drinks and human exposure assessment

Impact of textile composition, structure, and treatment on microplastic release during washing: a review

Impact of textile composition, structure, and treatment on microplastic release during washing: a review

Differences in the uptake and translocation of differentially charged microplastics by the taproot and lateral root of mangroves

The interception of microplastics (MPs) by mangrove roots plays an indispensable role in reducing the environmental risks of MPs. However, there remains limited research on the fate of the intercepted MPs. Hereby, the uptake and subsequent translocation of 0.2 μm and 2 μm PS MPs with different coating charge by the typical salt-secreting mangrove plants (Aegiceras corniculatum) were investigated. Compared to amino-functionalized PS with positive charge (PS-NH2), the visualized results indicated that the efficient uptake of carboxy-functionalized PS with negative charge (PS-COOH) was more dependent on taproots. But for the lateral roots, it only allowed the entry of PS-NH2 instead of PS-COOH. The specific uptake pathways of PS-NH2 on the lateral roots could attribute to the release of H+ and organic acids by root hairs, as well as the relative higher Zeta potential. After entering the Aegiceras corniculatum roots, the translocation of PS MPs was restricted by their particle sizes. Furthermore, the release of PS MPs from Aegiceras corniculatum leaf surfaces through the salt glands and stomata was observed. And the decline in the photochemical efficiency of leaves under PS MPs exposure also indirectly proved the foliar emission of PS MPs. Our study improved the understanding of the environmental behaviors and risks of the retained MPs in mangroves.

Microplastics or micro-bioplastics released by wrinkling paper cup

Paper cups have been widely used such as in the fast-food industry for drinking and are generally made of disposable material. To make the paper cup waterproof and prevent leakage, a thin layer of plastic such as polylactic acid (PLA) is commonly coated onto the inner wall surface. This plastic layer can potentially release debris as microplastics, particularly when the cup is wrinkled/crumpled to break and peel off the coating layer, which is tested herein. Using scanning electron microscope (SEM), the broken coating layer can be clearly observed. We then identify the coating material as plastic using mass and Raman spectra. We further employ Raman imaging to identify the released and fallen down debris as microplastics. We cross-check Raman image with SEM image to benefit each other and increase the analysis certainty, because Raman imaging can identify plastic via hyper spectrum to increase the signal-to-noise ratio, while SEM can visualise plastic with a high resolution down to micro-/nano- size. We then employ particle analysis algorithm to estimate the release amount, at approximate 180 microplastic/wrinkle, or micro-bioplastic if considering the main material of PLA as a bioplastic. Overall, we should not wrinkle the paper cup to avoid the potential release of microplastics or micro-bioplastics particularly before and during the drinking process, and the characterisation in this report might be helpful for further research on microplastics.

Microplastic Pollution and Risk Assessment in Packaged Teas in Türkiye

This article presents the first-ever findings on the release of MPs (microplastics) from tea bags containing tea leaves into tea infusions in Türkiye. The study aimed to investigate the possible distribution and abundance of MPs in cup of tea bags and teapot tea bags of fifteen packaged tea brands in Türkiye using ATF/FTIR analysis. The results showed that MPs were found in all the analyzed tea brands. Surprisingly, the highest particle number was observed in the dry tea samples (removed from tea bags) belonging to all brands. Brands A and O had the highest abundance of MPs. All MP particles identified were fiber in shape, and four colors were identified, with a predominance of navy blue. Polyethylene terephthalate (PET) was the most abundant polymer type. The size of MPs varied from 33.65 μm to 1680.20 μm. The daily MP exposure by tea intake was analyzed for male and female groups, and the dietary exposure for males was greater than that for females. According to the MP contamination factor values, a wide variety of MP contamination levels were determined, with a predominance of significant and very high levels of contamination. The mean polymer risk index was determined to be 10.80, indicating a low level of risk. Additionally, this study also provides information on the potential health effects of these harmful MPs. Considering that consuming tea is a significant way for individuals to come into contact with MPs, tea prepared with tea leaves packaged in tea bags could potentially have adverse effects on the health of consumers.Graphical

Safety assessment of polypropylene self-heating food container: The release of microplastics and volatile organic compounds

The safety assessment of food-contact plastic products is crucial for protecting consumers from potential harmful chemical contaminants. This study investigated novel contaminants and substances of concern in self-heating food containers, focusing on the release of microplastics (MPs) and the migration of volatile organic compounds (VOCs). Using micro-Raman spectroscopy, we simulated actual self-heating condition to determine the abundance, size, and size distribution of released MPs. Results showed MPs abundance ranging from 1.7 × 106 to 3.4 × 106 particles/L, with an average of 2.4 × 106 particles/L, where over 98 % of particles were smaller than 20 µm. For VOCs migration, we employed direct immersion solid-phase micro-extraction coupled with comprehensive two-dimensional gas chromatograph-tandem quadrupole-time-of-flight mass spectrometry (DI-SPME-GC×GC-QTOF-MS) under three migration conditions. We identified 41 VOCs, including saturated hydrocarbons, fatty acyls, organoxygen compounds, unsaturated hydrocarbons, benzene derivatives, and phenol ethers. Risk substances such as Dibutyl phthalate, Benzophenone, and 4-Methylbenzophenone were detected in three samples. Semi-quantitative analysis and toxicity classification revealed that the maximum migration of all analytes remained below corresponding limit values, indicating a generally low risk to consumers.

Microplastics in wastewater and sludge from centralized and decentralized wastewater treatment plants: Effects of treatment systems and microplastic characteristics

Domestic wastewater treatment plants (WWTPs) play a vital role in limiting the release of microplastics (MP) into the environment. This study examined MP removal efficiency from five centralized and four decentralized domestic WWTPs in Bangkok, Thailand. MP concentrations in wastewater and sludge were comparable between centralized and decentralized WWTPs, despite these decentralized WWTPs serving smaller populations and having limited treatment capacity. The elimination of MPs ranged from 50 to 96.8% in centralized WWTPs and 14.2–53.6% in decentralized WWTPs. It is noted that the retained MPs concentrations in sludge ranged from 20,000 to 228,100 MP/kg dry weight. The prevalence of synthetic fibers and fragments could be attributed to their pathways from laundry or car tires, and the accidental release of a variety of plastic wastes ended up in investigated domestic WWTPs. Removal of MPs between the centralized and decentralized WWTPs was influenced by several impact factors including initial MP concentrations, longer retention times, MP fragmentation, and variations of MP concentrations in sludge leading to different activated sludge process configurations. Sewage sludge has become a primary location for the accumulation of incoming microplastics in WWTPs. The MPs entering and leaving each unit process were varied due to the unique characteristics of MPs, and their different treatment efficiencies. While the extended hydraulic retention period in decentralized WWTPs decreased the MP removal efficacy, the centralized WWTP with the two-stage activated sludge process achieved the highest MP removal efficiency.

Microplastic Release from Single-Use Plastic Beverage Cups.

Microplastics (MPs) have attracted considerable attention as one of the most remarkable food and drink pollutants in recent years. Disposable cups, which are widely used as single-use containers, have been suspected as the primary sources of MPs found in cold and hot beverages. In this study, the effect of different exposure times (0, 5, 10 and 20 min) and temperatures (4 °C, 50 °C and 80 °C) on MP release from the single-use cups made of four different materials [polypropylene (PP), polystyrene (PS), polyethylene (PE) coated paper cups and expanded polystyrene (EPS)] into the water was investigated. The number of MPs ranged from 126 p/L to 1420 p/L, while the highest and lowest counts were observed in the PP (50 °C for 20 min) and PE-coated paper cups (4 °C 0 min), respectively. Washing the cups with ultrapure water prior to use reduced the MP release by 52-65%. SEM images demonstrated the abrasion on the surface of the disposable cups as a result of hot water exposure. Intensities of FTIR absorbance levels at some wavelengths were decreased by the water treatment, which could be evidence of surface abrasion. The annual MP exposure of consumers was calculated as 18,720-73,840 by the consumption of hot and cold beverages in disposable cups. In conclusion, as the level and potential toxicity of MP exposure in humans are not yet fully known, this study sheds light on the number of MPs transferred to cold and hot beverages from single-use disposable cups.

Rebuttal to Correspondence on "Assessing the Release of Microplastics and Nanoplastics from Plastic Containers and Reusable Food Pouches: Implications for Human Health".

Rebuttal to Correspondence on "Assessing the Release of Microplastics and Nanoplastics from Plastic Containers and Reusable Food Pouches: Implications for Human Health".

Assessment of mariculture-derived microplastic pollution in Dapeng Cove, China

Marine microplastic pollution just as ocean acidification and greenhouse effect has attracted much environmental concern and become a hot research subject for marine researchers globally. The abundances, distribution, and characteristics of microplastics in surface seawater and sediments from Dapeng Cove were investigated in this study. The results indicated that the abundance of microplastics was 1333 ± 773 items/m3 in surface seawater and 1381 ± 1021 items/kg in sediments, showing a medium microplastic pollution level compared with other sea areas. Fibers were the prevailing shapes of microplastics in both surface seawater and sediments, representing 65.4% and 52.1% of the total microplastic numbers, respectively. Moreover, small microplastics (<1mm) in surface seawater and sediments accounted for 69.6% and 62.2%, respectively. According to the identification by Fourier Transform Infrared microscope (micro-FTIR), the main composition of microplastics in surface seawater and sediments was polyethylene (PE) or polypropylene (PP). It is necessary to enhance the regulation of current plastic products used in aquaculture, reduce the production and release of microplastics during the mariculture process, and develop alternatives to plastic fishing gear. The results of this study suggested that long-term mariculture development had caused the accumulation of a large amount of microplastics in water and sediments in Dapeng Cove. We constructed the first basic data of microplastics pollution about Dapeng Cove. This study will serve as a reference for further studies of the distribution and migration of microplastics in mariculture zones.

Insights into short chain polyethylene penetration of phospholipid bilayers via atomistic molecular dynamics simulations

The escalation of global plastic production, reaching an annual output of 400 million tons, has significantly intensified concerns regarding plastic waste management. This has been exacerbated by improper recycling and disposal practices, contributing to the impending crisis of plastic pollution. Predictions indicate that by 2025, the environment will bear the burden of over ten billion metric tons of accumulated plastic waste. This situation has led to the concerning release of microplastics and nanoplastics (NPs) into the environment as plastic materials degrade, thereby posing risks to both ecosystems and human health. Nanoparticle interactions with living organisms have garnered significant attention due to their potential to disrupt vital biological processes. Of particular interest are lipid membranes, acting as crucial gatekeepers, underscoring the importance of comprehending the intricate process of NP penetration. Molecular dynamics (MD) simulations serve as a robust tool, offering molecular-level insights into these intricate interactions. In this study, we leverage all-atom MD simulations to delve into the interactions between lipid bilayers and polyethylene (PETH) chains of varying lengths. The investigation spans diverse lipid bilayer compositions—ranging from pure POPC to POPC:DPPC mixtures—revealing how PETH accommodates itself, adopts extended conformations, and influences membrane structure and ordering. Significantly, while longer PETH chains demonstrate limited passive diffusion, their potential to penetrate bilayers over extended timescales emerges as a significant revelation. Overall, this research significantly advances our comprehension of NP-membrane interactions, shedding light on the potential environmental and health implications that lie ahead.

Release of fibrous microplastics from functional polyester garments through household washing

The global increase of the amount of microplastics in aquatic systems is an ever-growing problem. Household laundering of synthetic textiles has been identified as one significant reason for the release of fibrous microplastics (FMP), although a high proportion of the waste water generated by the washing process is filtered by wastewater treatment plants, e.g., in Germany, before it enters the environment. The washing of garments made of synthetic materials is considered particularly and was investigated during this study. Therefore, 11 fleece garments, one mixed batch and three non-raised garments were washed several times and under different conditions in houshold washing machines. However, this study utilizing different functional polyester garments showed that mechanical raised textiles (e.g., fleece) do not generally have higher emission values than non-raised textiles, such as sports shirts and sports pants. During the washing process, the release of FMP can be influenced by different washing parameters, always aiming for a good washing result. The experiments showed, that the release of FMP into the aquatic environment can be reduced by the washing habits—especially a high washing machine load and a shortened washing time were found to be effective.

Exploring the release mechanism of micro/nanoplastics from different layers of masks in water: towards reduction of plastic contamination in masks.

During the COVID-19 pandemic, a substantial quantity of disposable face masks was discarded, consisting of three layers of nonwoven fabric. However, their improper disposal led to the release of microplastics (MPs) and nanoplastics (NPs) when they ended up in aquatic environments. To analyze the release kinetics and size characteristics of these masks, release experiments were performed on commercially available disposable masks over a period of 7days and micro- and nanoplastic releases were detected using fiber counting and nanoparticle tracking analysis. The study's findings revealed that there was no significant difference (p > 0.05) in the quantity of MPs released among the layers of the masks. However, the quantity of NPs released from the middle layer of the mask was 25.9 ± 1.3 × 108 to 81.3 ± 5.3 × 108 particles/piece, significantly higher than the inner and outer layers (p < 0.05). The release process of micro/nanoplastics (M/NPs) from each layer of the mask followed the Elovich equation and the power function equation, indicating that the release was divided into two stages. MPs in the range of 1-500µm and NPs in the range of 100-300nm dominated the release from each layer of the mask, accounting for an average of 93.81% and 67.52%, respectively. Based on these findings, recommendations are proposed to reduce the release of M/NPs from masks during subsequent use.