Microplastic Fibers Research Articles

Characterization of microplastics in indoor and ambient air in northern New Jersey

Airborne microplastics (MPs) could have negative impacts on human health and pollute water, soil, and sediment. This study explored the distributions, compositions, and morphology of airborne microplastics in the indoor and ambient air in New Jersey, United States. Microplastic fibers, films, and fragments of Polystyrene (PS), Polyethylene terephthalate (PET), Polyethyelene (PE), Polyvinyl chloride (PVC) and Polypropylene (PP) were identified in office, hallway, classroom, and single-family house in this study. The deposition rates of synthetic fibers with length from 35 μm to 1000 μm were highest in the single-family house ((1.96 ± 1.09) × 104 fibers/m2/day) and lowest in the classroom ((6.20 ± 0.57) × 103 fibers/m2/day), suggesting that residential houses are a major source of microplastic fibers. However, for film-like plastics with surface areas ranging from 200 μm2 to 5000 μm2, a high deposition rate of (8.13 ± 2.17) × 103 films/m2/day was observed in the classroom, whereas the lowest deposition rate of (4.45 ± 0.27) × 103 films/m2/day was found in the hallway, probably because plastic films such as PE are intensively used in the classroom environments. The deposition rate of microplastics in the ambient air acquired on a building roof was only about 2–8% of the indoor deposition rates. The microplastics with similar textures but different sizes were identified in both total atmospheric deposition and particulate samples (PM2.5 and PM10), suggesting degradation from microplastics to nanoplastics. The main microplastics found in indoor air samples were PE fragments or fibers, different from those in the outdoor ambient air that were dominated by PVC fragments. These results unravel the properties of airborne microplastics in urban environments that are important to understanding their fate, transport, and potential health risks.

Characterization of atmospheric aerosols in the Antarctic region using Raman Spectroscopy and Scanning Electron Microscopy

The non-destructive spectroscopic characterization of airborne particulate matter (PM) was performed to gain better knowledge of the internal structures of atmospheric aerosols at the particle level in the Antarctic region, along with their potential sources. PM and soil samples were collected during the 2016–2017 austral summer season at the surroundings of the Spanish Antarctic Research Station “Gabriel de Castilla” (Deception Island, South Shetland Islands). PM was deposited in a low-volume sampler air filter. Raman spectroscopy (RS) and Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopy (SEM-EDS) were used to determine the elemental and molecular composition of the individual aerosol and soil particles. Filter spectra measured by these techniques revealed long-range atmospheric transport of organic compounds (polystyrene and bacteria), local single and cluster particles made of different kinds of black carbon (BC), exotic minerals (polyhalite, arcanite, niter, ammonium nitrate, syngenite and nitrogen, phosphorus, and potassium (NPK) fertilizer), and natural PM (sea salts, silicates, iron oxides, etc.). In addition to the filter samples, forsterite and plagioclase were discovered in the soil samples together with magnetite. This is the first report of the presence of a microplastic fiber in the Antarctic air. This fact, together with the presence of other pollutants, reflects that even pristine and remote regions are influenced by anthropogenic activities.

Prevalence of microplastic fibers in the marginal sea water column off southeast China

Microplastic (MP) fibers are present in all environmental media, yet little is known about their distribution, sources, and transport in the water column of marginal seas. In this study, we conducted an intensive sampling campaign in the marginal sea water column off southeast China, which is an area that is greatly influenced by high MP emissions. We found that hydrological effects largely regulated the spatial variations of MP fiber distribution and that MP fibers likely were not entering the South China Sea through terrestrial input from southeast China during the summer monsoon. Polyethylene terephthalate (PET) fibers were pervasive in the surface water (SW) (89.47%), subsurface chlorophyll maximum layer (SCML) (92.65%), and bottom water (BW) (94.29%) of the water column during the sampling period. Approximately 32% of MP fibers in the samples were smaller than 330 μm. The abundance of MP fibers in SW was significantly lower than that in the SCML and BW. Based on this observation, we estimated the inventory of MP fibers in the SW, SCML, and BW of the sampling area to be 1.377–1.378, 2.820–2.825, and 2.627–2.629 metric tons, respectively. These results improved our understanding of the source-to-sink process of MP fiber contamination in the water column of marginal seas.

Analysis of Microplastics Released from Plain Woven Classified by Yarn Types during Washing and Drying.

Microplastics reach the aquatic environment through wastewater. Larger debris is removed in sewage treatment plants, but filters are not explicitly designed to retain sewage sludge’s microplastic or terrestrial soils. Therefore, the effective quantification of filtration system to mitigate microplastics is needed. To mitigate microplastics, various devices have been designed, and the removal efficiency of devices was compared. However, this study focused on identifying different fabrics that shed fewer microplastics. Therefore, in this study, fabric-specific analyses of microplastics of three different fabrics during washing and drying processes were studied. Also, the change in the generation of microplastics for each washing process of standard washing was investigated. The amount of microplastics released according to the washing process was analyzed, and the collected microplastics’ weight, length, and diameter were measured and recorded. According to the different types of yarn, the amount of microplastic fibers produced during washing and drying varied. As the washing processes proceed, the amount of microplastics gradually decreased. The minimum length (>40 µm) of micro-plastics generated were in plain-woven fabric. These results will be helpful to mitigate microplastics in the production of textiles and in selecting built-in filters, and focusing on the strict control of other parameters will be useful for the development of textile-based filters, such as washing bags.

Preliminary results on microplastics in surface water from the downstream of the Day River

Microplastics (MPs), referring to plastic items ranging from 1 to 5000 µm long, are polluting the terrestrial and aquatic environments and are becoming a threat to the health of ecosystems, biota, and humans. Rivers are major carriers of these materials from the terrestrial environment to the oceans. In the present study, the occurrence of MPs in a peri-urban river was investigated. The Day river system is a good example of a peri-urban river strongly influenced by human activities in the whole basin. Water samples were collected from the downstream of the Day river, including Cau Que, Cau Do, and Do Thong, in the rainy and dry seasons using a plankton sampling net for identifying microplastic concentration, size, shape, color, and polymer composition. Microplastic abundance in the surface water ranged from 269,693±60,624 to 863,005±131,925 items/m3. The microplastic concentration in the rainy season was higher than that in the dry season. MPs abundance was increased at a site near urban areas with high human activity. The microplastic shape was collected in different seasons did not change significantly, with microplastic fibers as the major items, accounting for above 92% of the total items. Many fibers microplastics collected in this study were in small sizes of 300-1000 µm and 1000-2000 µm, occupying 78.5-85.7% of the total microplastic items. Purple was the most common color of microplastics. Polyethylene (PE) and polypropylene (PP) were major polymer types of the selected items in the surface water samples downstream of the Day River.

A Holistic Assessment of Polyethylene Fiber Ingestion in Larval and Juvenile Japanese Medaka Fish.

Microplastic pollution is of public concern for global environmental health, aquaculture, and fisheries. Toxicity studies have shown that microplastic ingestion may cause intestinal damage, microbiota dysbiosis, and disturb the lipid and energy metabolism in fish. To determine the impact of environmentally relevant, chronic, low dose microplastic fibers on fish health, medaka larvae, and juveniles were exposed to five concentrations of polyethylene (PE) fibers for 21 days through the feed. Fish growth and condition were assessed to determine the overall impact on fish health. To identify impaired energy intake, the gastrointestinal tract (GIT) integrity was evaluated at the molecular and cellular levels. Microbiota analysis was performed by comparing the top seven most abundant phyla present in both larval and juvenile fish exposed to 0, 1.5, and 3 PE fibers/fish/day. A shift in the phyla Proteobacteria and Bacteroidetes were observed. Larval samples demonstrated decreased proteobacteria abundance, while juvenile samples displayed an increase in abundance. Relative gene expression of key digestive genes from GIT tissue was quantified using real time-quantitative polymerase chain reaction. An effect on digestive gene expression potentially affecting nutrient absorption and antioxidant production was indicated via a significant decrease of solute carrier family 6 member 6 expression in larvae exposed to 6 fibers/fish/day. No significant molecular changes were observed in juvenile GIT tissue, although a non-monotonous dose-response was observed. GIT morphology was analyzed using histomorphological observations of the GIT mucus and cell types. No significant impairment of the GIT epithelial layers was observed in larvae or juveniles. To assess growth and condition, Fulton’s condition factor was measured. No differences were observed in larval or juvenile growth. Comparisons of different developmental stages allowed for identifying vulnerable developmental stages for microplastic exposure; larvae were more susceptible to molecular changes, while shifts in juvenile microbial communities were similar to changes reported post-polystyrene microplastic sphere exposure. This study is one of the first to provide toxicological data on the risk of PE fiber ingestion during fish development stages. Results indicate no imminent threat to fish condition at current measured environmental levels of microplastics; however, close monitoring of vital spawning grounds for commercially important fishes is recommended.

Microplastic and Organic Fibres in Feeding, Growth and Mortality of Gammarus pulex

Microplastic fibres (MPFs) are a major source of microplastic pollution, most are released during domestic washing of synthetic clothing. Organic microfibres (OMF) are also released into the environment by the same means, with cotton and wool being the most common in the UK. There is little empirical evidence to demonstrate that plastic fibres are more harmful than organic fibres if ingested by freshwater animals such as Gammarus pulex. Using our method of feeding Gammarus MPFs embedded in algal wafers, we compared the ingestion, feeding behaviour and growth of Gammarus exposed to 70 µm sheep wool, 20 µm cotton, 30 µm acrylic wool, and 50 µm or 100 µm human hair, and 30 µm cat hair at a concentration of 3% fibre by mass. Gammarus would not ingest wafers containing human hair, or sheep wool fibres. Given the choice between control wafers and those contaminated with MPF, cat hair or cotton, Gammarus spent less time feeding on MPF but there was no difference in the time spent feeding on OMFs compared to the control. Given a choice between contaminated wafers, Gammarus preferred the OMF to the MPF. There were no significant differences in growth or mortality among any of the treatments. These results conclude that MPFs are less likely to be ingested by Gammarus if alternative food is available and are not more harmful than OMFs.

Life-cycle environmental impact assessment and plastic pollution prevention measures of wet wipes

Wet wipes have become one of the daily necessities for consumers. The spunlace non-woven fabric, whose main raw materials are petroleum-based fibers (mainly polyester fibers) and bio-based fibers (mainly viscose fibers), is the predominant component of wet wipes. The use of wet wipes triggers the increasing plastic consumption and environmental pollution. In the current study, the materials composition of China's wet wipes and final disposal methods were performed. The basic data of materials of wet wipes was obtained through field research. The study also evaluated and compared the life cycle environmental impacts of bio-based and petroleum-based wet wipes. Results showed that in China, the amount of plastic used in wet wipes reached 0.41 million tons in 2019. As for the comparison between distinct types of wet wipes, the comprehensive environmental impacts of bio-based wet wipes throughout the life cycle is 38% lower than that of petroleum-based wet wipes. The bio-based wet wipes outperform the petroleum-based ones in the lower resource consumption and toxicity risk, albeit it may induce water pollution. In the direct leakage scenario, bio-based wet wipes can avoid various risk of microplastic fibers disintegrated by polyester fibers. The main findings of this paper support the policy suggestions that bio-based wet wipes are proper alternatives for petroleum-based wet wipes, and it is essential to change consumers’ discarding behaviours to attenuate the leakage risk of wet wipes.

Microplastic Fibers Increase Sublethal Effects of AgNP and AgNO3 in Daphnia magna by Changing Cellular Energy Allocation.

The effects of combined exposure to microplastics and contaminants are still not completely understood. To fill this gap, we assessed the effects of polyethylene terephthalate microplastic fibers (100 mg/L; 360 µm average length) on the toxicity of silver nanoparticles (AgNPs; 32 nm) and silver nitrate (AgNO3 ; 0.1-10 µg Ag/L) to Daphnia magna. Acute immobilization (median effect concentration [EC50]) and cellular energy allocation (CEA; ratio between available energy and energy consumption) were determined in neonates (<24 h old) and juveniles (7 d old), respectively. The 48-h EC50 for AgNP and AgNO3 (2.6 and 0.67 µg Ag/L, respectively) was not affected by the presence of microplastic fibers (2.2 and 0.85 µg Ag/L, respectively). No decrease in the available energy was observed: lipid, carbohydrate, and protein contents were unaffected. However, a significant increase in energy consumption was observed in animals exposed to AgNO3 (250% compared with control) and to the combination of microplastic fibers with AgNP (170%) and AgNO3 (260%). The exposure to microplastic fibers alone or in combination with both Ag forms decreased the CEA (values were 55-75% of control values). Our results show that after short-term exposure (48 h), microplastic fibers increased Ag toxicity at a subcellular level (i.e., CEA), but not at the individual level (i.e., immobilization). These results highlight the importance of combining different levels of biological organization to fully assess the ecotoxicological effects of plastics in association with environmental contaminants. Environ Toxicol Chem 2022;41:896-904. © 2021 SETAC.

Microplastics pollution on Colombian Central Caribbean beaches

The growing literature on microplastics (MPs) in coastal and marine environs reflects the seriousness of this pollutant category. Diverse litter studies on Colombia's Central Caribbean Coast have not presented detailed study of MPs' typology, magnitude or distribution. This baseline study presents for first time the MPs problem on 23 beaches in 75 km coastal reach between Punta Roca and Galerazamba, on the central Colombian Caribbean Coast. The Microplastics Pollution Index (MPPI) and Coefficient of Microplastic Impact (CMPI) were developed and applied along with the Environmental Status Index (ESI) and their integration through sector analysis, and mapping using Agglomerative Hierarchical Clustering and Multidimensional Scaling, and Principal Components Analysis. Microplastics abundances (densities) ranged from 2457 to 557 MPs/kg, similar to other global beaches and bays. The MPs Index for the 23 beaches classified 8 beaches as “Moderate,” 10 beaches as “High” and 5 as “Very High.” Microplastic fibers were the dominant typology at 83% of the combined beaches total (ranging from Moderate to Very High for individual beaches).

Facemasks: A Looming Microplastic Crisis.

Single-use disposable facemasks have been used as a preventive measure against the ongoing COVID-19 pandemic. However, many researchers have found evidence that these facemasks are being dumped into lakes, rivers, and open garbage dumps. Facemasks have the potential of releasing microplastic fibers into the environment; a phenomenon that has been poorly investigated. Moreover, microplastic fibers composed of plastics have the potential of affecting the flora and fauna of many ecosystems. In this preliminary study, we investigate how many microplastic fibers had been released to the water by KF-AD, KF94, surgical, and FFP1 standard facemasks, which are the most widely available facemask standards in South Korea. The waterbody in our research was mechanically agitated for 24, 48, and 72 h. Findings showed that most of the layers of facemasks are composed of polypropylene. The surgical and KF94 standard facemasks released the highest number of microplastic fibers. Furthermore, under our research conditions, a single facemask can release at least 47 microplastic fibers per day (e.g., KF-AD standard mask), which can lead to the release of at least 1381 million microplastic fibers per day in total in South Korea if 70% of the urban population uses a single mask every day. Moreover, the released microplastic fibers significantly increased when the agitation time extended from 24 to 48 h. This finding suggests that the number of released microplastic fibers is likely to increase drastically.

Uncovering the release of micro/nanoplastics from disposable face masks at times of COVID-19

Wearing face masks is a fundamental prevention and control measure to limit the spread of COVID-19. The universal use and improper disposal of single-use face masks are raising serious concerns for their environmental impact, owing to the foregone contribution to plastic water pollution during and beyond the pandemic. This study aims to uncover the release of micro/nanoplastics generated from face mask nonwoven textiles once discarded in the aquatic environment. As assessed by microscopy and flow cytometry, the exposure to different levels of mechanical stress forces (from low to high shear stress intensities) was proved effective in breaking and fragmenting face mask fabrics into smaller debris, including macro-, micro-, and nano-plastics. Even at the low level of fabric deterioration following the first second of treatment, a single mask could release in water thousands of microplastic fibers and up to 108 submicrometric particles, mostly comprised in the nano-sized domain. By contributing to the current lack of knowledge regarding the potential environmental hazards posed by universal face masking, we provided novel quantitative data, through a suitable technological approach, on the release of micro/nanoplastics from single-use face masks that can threaten the aquatic ecosystems to which they finally end-up.

Biofilms Enhance the Adsorption of Toxic Contaminants on Plastic Microfibers under Environmentally Relevant Conditions.

Microplastics (MPs) exposed to the natural environment provide an ideal surface for biofilm formation, which potentially acts as a reactive phase facilitating the sorption of hazardous contaminants. Until now, changes in the contaminant sorption capacity of MPs due to biofilm formation have not been quantified. This is the first study that compared the capacity of naturally aged, biofilm-covered microplastic fibers (BMFs) to adsorb perfluorooctane sulfonate (PFOS) and lead (Pb) at environmentally relevant concentrations. Changes in the surface properties and morphology of aged microplastic fibers (MF) were studied by surface area analysis, infrared spectroscopy, and scanning electron microscopy. Results revealed that aged MFs exhibited higher surface areas because of biomass accumulation compared to virgin samples and followed the order polypropylene>polyethylene>nylon>polyester. The concentrations of adsorbed Pb and PFOS were 4-25% and 20-85% higher in aged MFs and varied among the polymer types. The increased contaminant adsorption was linked with the altered surface area and the hydrophobic/hydrophilic characteristics of the samples. Overall, the present study demonstrates that biofilms play a decisive role in contaminant-plastic interactions and significantly enhance the vector potential of MFs for toxic environmental contaminants. We anticipate that knowledge generated from this study will help refine the planetary risk assessment of MPs.

Smoked cigarette butts: Unignorable source for environmental microplastic fibers

The pollution of microplastics and their potential environmental hazards have attracted considerable attention of the public. Cigarette butts, composed of cellulose acetate, are one of the most common plastic pollutants in the environment. Of all the litter that is discarded at will, cigarette butts are the most acceptable. Cigarette butts are dangerous pieces of plastic, but are usually not handled properly and consist of more than 15,000 detachable strands of plastic fiber. Discarded cigarette butts may be carried into rivers and lakes, and finally into the ocean. The plastic fibers will continuously release microplastic fibers into the environment. About 300,000 tons of potential microplastic fibers may enter the aquatic environment from this source per annum. Additionally, toxic substances, such as nicotine, carcinogenic tar, and polycyclic aromatic hydrocarbons, have strong toxic effect, which will cause serious damage to aquatic organisms. However, the mechanism and rate of microplastic fibers release from smoked cigarette butts and the joint toxicity of microplastic fibers and toxic pollutants to aquatic organisms are still in the initial stage. Therefore, it is necessary to understand the mechanism of cigarette butts releasing microplastic fibers, the potential impact on the environment and possible measures to reduce the impacts of cigarette butt litter. The aim of this paper is to evaluate the potential sources of smoked cigarette butts as environmental fiber microplastics and the potential ecological effects of the released microplastic fibers on the ecosystem. In addition, some ways which could help to tackle problem of smoked cigarette butts pollution have also been proposed.

Synthetic textile and microfiber pollution: a review on mitigation strategies.

Microfiber pollution is one of the recent threats to sustainability. Due to the increased use of synthetic textiles, microplastic fiber release to the environment has increased exponentially. This review aims to analyze the existing literature to identify the potential preventive measures to control microfiber pollution. The review consolidates the findings under the textile properties and laundry product category. The review results show that the use of finer count yarns with filaments and compact structures reduces microfiber shedding. Similarly, mechanical finishes like shearing and raising increase the microfiber release as they damage the fabric structure. A significant increment is noted in microfiber reduction percentage after the chemical (coating) finishing process. In the case of commercial products, the available external laundry filters are reported as more efficient than the in-drum devices in the market. An analysis of the existing regulatory norms showed that very few countries had developed their laws, and no global regulation and standards were found to test microfiber pollution. In the case of laundry filters, though they filter microfiber effectively, they do not prevent it, so it can be a control measure and not a solution for the issue. Out of the review results, it is identified that controlling the textile parameter is the only effective strategy to prevent the microfiber shedding from the synthetic textile. A proper production method and parameter will yield a textile that sheds lesser or no microfiber. However, no detailed research works are found in correlating these parameters together and indicate the potential scope for future research.

Microplastic Fiber Emissions From Wastewater Effluents: Abundance, Transport Behavior and Exposure Risk for Biota in an Arctic Fjord

Microfibers (MF) are one of the major classes of microplastic found in the marine environment on a global scale. Very little is known about how they move and distribute from point sources such as wastewater effluents into the ocean. We chose Adventfjorden near the settlement of Longyearbyen on the Arctic Svalbard archipelago as a case study to investigate how microfibers emitted with untreated wastewater will distribute in the fjord, both on a spatial and temporal scale. Fiber abundance in the effluent was estimated from wastewater samples taken during two one-week periods in June and September 2017. Large emissions of MFs were detected, similar in scale to a modern WWTP serving 1.3 million people and providing evidence of the importance of untreated wastewater from small settlements as major local sources for MF emissions in the Arctic. Fiber movement and distribution in the fjord mapped using an online-coupled hydrodynamic-drift model (FVCOM-FABM). For parameterizing a wider spectrum of fibers from synthetic to wool, four different density classes of MFs, i.e., buoyant, neutral, sinking, and fast sinking fibers are introduced to the modeling framework. The results clearly show that fiber class has a large impact on the fiber distributions. Light fibers remained in the surface layers and left the fjord quickly with outgoing currents, while heavy fibers mostly sank to the bottom and deposited in the inner parts of the fjord and along the northern shore. A number of accumulation sites were identified within the fjord. The southern shore, in contrast, was much less affected, with low fiber concentrations throughout the modeling period. Fiber distributions were then compared with published pelagic and benthic fauna distributions in different seasons at selected stations around the fjord. The ratios of fibers to organisms showed a very wide range, indicating hot spots of encounter risk for pelagic and benthic biota. This approach, in combination with in-situ ground-truthing, can be instrumental in understanding microplastic pathways and fate in fjord systems and coastal areas and help authorities develop monitoring and mitigation strategies for microfiber and microplastic pollution in their local waters.

A preliminary analysis of ingestion and egestion of microplastic fibres in the acorn barnacle Balanus glandula

Microplastic contamination is a growing threat facing marine ecosystems, of which a prominent source is the fibres from synthetic clothing. Ingestion and egestion (excretion) of microfibres, and whether these have short-term effects on behaviours such as feeding rate, have yet to be studied in many organisms, especially non-bivalve filter feeders. To determine if a common, filter feeding, intertidal invertebrate can ingest microfibres, we studied the acorn barnacle (Balanus glandula Darwin 1854). We collected B. glandula from four locations near Bamfield, British Columbia, Canada, exposed half of them to a high concentration (~70,000 microfibres/L) of brightly coloured polyester microfibres for 24 h in unfiltered seawater (while the other half received a non-exposure treatment), and measured the feeding rates of the barnacles before and after the exposure. An average of 1.2 ± 1.9 fibres per barnacle were present in the gastrointestinal tracts of the plastic treatment group before depuration, and 0.3 ± 0.6 fibres per barnacle were found in the corresponding control group. Prior to depuration, 50% of the 20 barnacles in the plastic treatment ingested at least one microfibre, while a 15% ingestion rate was observed in the control group. There was no detectable short-term effect of microfibre ingestion on feeding rate. A 48-h post plastic exposure depuration period was used to evaluate whether microplastics were egested. No difference in egestion was found between those assessed directly after exposure and those that underwent depuration. Furthermore, a low depuration rate of 0.05 microfibres per 48 h suggests that barnacles may require longer than 48 h to egest microfibres. If representative, these results indicate that acorn barnacles ingested few microfibres even when exposed at very high concentrations, which supports the idea that they are at low risk for microplastic contamination and would not be a suitable indicator species.

Formation of Fiber Fragments during Abrasion of Polyester Textiles.

Fiber fragments are one of the dominant types of microplastics in environmental samples, suggesting that synthetic textiles are a potential source of microplastics to the environment. Whereas the release of microplastics during washing of textiles is already well studied, much less is known about the release during abrasion processes. The abrasion of textiles may induce fibrillation of fibers and therefore result in the formation of much finer fiber fragments. The aim of this study was to investigate the influence of abrasion of synthetic textiles on the formation of microplastic fibers and fibrils. Fleece and interlock textile swatches made of polyester were abraded using abrasion tests with a Martindale tester. The microplastic fibers and fibrils formed during abrasion were extracted from the textiles and characterized in terms of number, length, and diameter. The microplastic fibers demonstrated the same diameter than the fibers found in the textiles (fleece: 12.3 μm; interlock: 12.7 μm), while fibrils with a much smaller diameter (fleece: 2.4 μm; interlock: 4.9 μm) were also found. The number of fibrils formed during abrasion in both textiles was higher than the number of microplastic fibers. The majority of the extracted microplastic fibers had a length between 200 and 800 μm, while most fibrils were between 30 and 150 μm, forming two distinct fiber fragment morphologies. The number of microplastic fibers formed during abrasion was 5 to 30 times higher than the number of microplastic fibers that could be extracted from non-abraded samples. The number of fibrils increased after abrasion by more than a factor of 200 for both fabric types. The fibrils formed during abrasion have diameters that fall within the inhalable size for airborne particles. The potential release of fibrils into air during wear of textiles thus raises questions about the human exposure to these materials. Since the Martindale tester can simulate a daily application scenario of textiles over a prolonged period only in a limited way, future studies are needed to establish the correlation between the test results with a real-world scenario.

Neglected microplastics pollution in global COVID-19: Disposable surgical masks

There have been many studies on the microplastic pollution, influence and control mechanisms of different plastic products. The potential harm of microplastic pollution to the environment has been confirmed. With the outbreak and spread of the COVID-19 in the world, disposable surgical masks as effective and cheap protective medical equipment have been widely used by the public. Disposable masks have been a new social norm, but they must have a sense of environmental responsibilities. The random disposal of masks may result in new and greater microplastic pollution, because masks made of polymer materials would release microplastics after entering the environment. Current results showed that masks are a potential and easily overlooked source of environmental microplastics. The release amount of microplastics in the static water by one mask was 360 items, and with the increase of vibration rate, the release amount also increased. The addition of organic solvents (detergent and alcohol) in water would increase the release of microplastics from masks. When the mask became fragments, the ability to release microplastic fibers into the environment was greatly improved due to the increase of exposure area. After two months of natural weathering, the masks become very fragile pieces and microplastics. A fully weathered mask could release several billions of microplastic fibers into the aquatic environment once these fragile fragments enter the water without reservation. The rapid growth of mask production and consumption and improper disposable is worrying. It is urgent to understand the potential environmental risks and significance of masks.

Microplastic fibers influence Ag toxicity and bioaccumulation in Eisenia andrei but not in Enchytraeus crypticus.

Microplastic fibers (MF) are released from synthetic textiles during washing and end up in the wastewater. Similarly, silver nanoparticles (AgNP), incorporated in textiles as antimicrobial agents, are released in washing machines, also reaching the wastewater treatment plants. Therefore, both MF and AgNP co-exist in the environment and enter the soil compartment mainly via the application of biosolids. Yet, the combined effect of MF and AgNP has not been studied. Here, we assessed the effects of polyester MF on the toxicity of AgNP and AgNO3 to the earthworm Eisenia andrei and the enchytraeid Enchytraeus crypticus. The organisms were exposed to a range of concentration of AgNP (32, 100, 320, 1000, 3200 mg Ag/kg) and AgNO3 (12.8, 32, 80, 200, 500 mg Ag/kg) in LUFA 2.2 soil in the absence or presence of MF (0.01% DW). Reproduction tests were conducted and the toxicity outcomes compared between soils with and without MF. The exposure to MF caused a decrease in the number of juveniles and changed the biochemical composition of earthworms. Moreover, the presence of MF increased the toxicity of AgNP to earthworm reproduction (EC50 = 165 mg Ag/kg) when compared to AgNP exposure alone (EC50 = 450 mg Ag/kg), but did not alter the toxicity of AgNO3 (EC50 = 40 mg Ag/kg). For enchytraeids, no significant difference in Ag toxicity could be detected when MF was added to the soil for both AgNP and AgNO3. Overall, Ag bioaccumulation was not affected by MF, except for a decrease in earthworm body concentration at the highest Ag soil concentration (3200 mg Ag/kg). Our results suggest that the presence of MF in the soil compartment may be a cause of concern, and that the joint exposure to Ag may be deleterious depending on the Ag form, organism, and endpoint. The present work provides the first evidence that a realistic MF concentration in soil lowers AgNP concentration necessary to provoke reproductive impairment in earthworms. The influence of MF on the risk assessment of AgNP should be considered.