Release Of Microplastics Research Articles

Classification and identification of polar pollutants on microplastics from freshwater using nontarget screening strategy

Microplastics (MPs) cause an increased threat to the freshwater environment by adsorbing pollutants on their large surface area. Considering their adsorption characteristics, non-polar pollutants with high distribution coefficients have been studied extensively. However, comprehensive research on the types of polar pollutants adsorbed by MPs is lacking. In this study, a nontarget screening strategy, including classification and identification, was performed to analyze the pollutants adsorbed by MPs in Tai Lake and the Yangtze River. Compared with the pollutants adsorbed or added to raw plastics, more types of polar pollutants were found on MPs from freshwater. The nontarget classification of 4723 features on MPs from freshwater and 680 features from raw plastics were annotated based on the mass spectrometry spectra. Further identification with multiple platforms identified hundreds of pollutants absorbed by MPs in Tai Lake and Yangtze River, including industrial intermediates, medicines, and surfactants, exceeding those adsorbed by raw plastics, showing an enrichment of the pollutants on MPs in freshwater by secondary adsorption. Our study is the first to use nontarget analysis to comprehensively demonstrate MP adsorption and release of pollutants in freshwater environment, providing a significant reference for the research of MPs and the management of the water environment.

Millions of microplastics released from a biodegradable polymer during biodegradation/enzymatic hydrolysis

In this article, we show that enzymatic hydrolysis of a biodegradable polyester (poly(ε-caprolactone)) by Amano Lipase PS in an aqueous (buffer) environment yielded rapidly an excessive number of microplastic particles; merely 0.1 g of poly(ε-caprolactone) film was demonstrated to yield millions of particles. There were also indications of non-enzymatic hydrolysis at the same conditions, but this did not yield any particles within the time frame of the experiment (up to 6 days). Microplastic particles formed had irregular shapes with an average size of around 10 µm, with only a few reaching 60 µm. The formation of microplastic particles resulted from the uneven hydrolysis/erosion rate across the polymer film surface, which led to a rough and undulating surface with ridge, branch, and rod-shaped micro-protruding structures. The consequent detachment and fragmentation of these micro-sized protruding structures resulted in the release of microplastics to the surroundings. Together with microplastics, hydrolysis products such as acidic monomers and oligomers were also released during the enzymatic hydrolysis process, causing a pH decrease in the surrounding liquid. The results suggest that the risk of microplastic pollution from biodegradable plastics is notable despite their biodegradation. Special attention needs to be paid when using and disposing of biodegradable plastics, considering the enormous impact of the paradigm shift towards more biodegradable products on the environment.

An enhanced risk assessment framework for microplastics occurring in the Westerscheldt estuary

Microplastics (MPs) pollution in the aquatic environment raises considerable concerns. Freshwater system is generally considered as an important source for MPs transformation into the marine environment, however, only limited data on the MPs pollution in global freshwater systems is available at this time. In this study, we explored the abundance, characteristics and distribution of microplastics in the Scheldt River. The investigation results indicated that the abundance of microplastics in sediments (15–413 items/kg dry weight (DW)) was much higher than that in surface water (0–113 items/m3), and small size MPs (less than 500 μm) frequently appeared in sediments. Industrial activities were regarded as the major cause of MP discharging. Risk assessment models with using data of the concentration of MPs, polymer types and toxicity of MPs exposure were developed to assess the risk of MPs pollution in both surface water and sediment of the Westerscheldt estuary. Risk assessment results revealed that MPs exposure have potentially adverse effects on the aquatic ecosystem and human health. MPs tend to be transported from “Hotspots”, such as urban or industries area, to remote areas. The risk assessment of MPs serves as a baseline for better understanding the distribution and characteristics of MPs and highlights the need of intensively monitoring to limit MPs release by intensively monitoring. This research provides a perspective on the risk of MPs that could be used in future studies.

Discharge of Micro Plastics by Drum Type Home Laundering of Fleece Cloth

Discharge of Micro Plastics by Drum Type Home Laundering of Fleece Cloth

Release of Microplastics from Disposable Cups in Daily Use

Release of Microplastics from Disposable Cups in Daily Use

Release of Microplastics and Nanoplastics in Aqueous Environments from Disposable Surgical Masks after Disinfection

Release of Microplastics and Nanoplastics in Aqueous Environments from Disposable Surgical Masks after Disinfection

The Surface Degradation and Release of Microplastics from Plastic Films Studied by Uv Radiation and Mechanical Abrasion

The Surface Degradation and Release of Microplastics from Plastic Films Studied by Uv Radiation and Mechanical Abrasion

Long-Term Kinetic Characteristics of Microplastic Release From Commonly Used Masks Into Water Under Simulated Natural Environments

Long-Term Kinetic Characteristics of Microplastic Release From Commonly Used Masks Into Water Under Simulated Natural Environments

Release of microplastics from typical rainwater facilities during aging process

As the demand for urban flood prevention and drainage increases, a large number of plastic rainwater facilities are in use. Microplastics will be released inevitably into stormwater systems during aging and hydraulic scouring processes, which could cause potential pollution risk. This study simulated the release behavior of microplastics from three typical plastic rainwater facilities including a rainwater inspection well, rainwater storage module, and rainwater pipe (mainly composed of high-density polyethylene, polypropylene, and polyvinyl chloride, respectively) under the effects of aging and hydraulic scouring. After 15–45 days of UV aging and 72 h of hydraulic scouring, the surfaces of the three facilities were found to exhibit increases in roughness, cracks, folds, and cavities, with the most pronounced changes occurring in the rainwater storage module. As the aging time increased, oxygen-containing functional groups formed and led to carbon chain scission. Fourier transform infrared spectroscopy (FTIR), two-dimensional correlation spectroscopy (2D-COS) and X-ray photoelectron spectroscopy (XPS) of facility surfaces showed that the formation of oxygen-containing functional groups was an important factor affecting the release of microplastics. The amount of microplastics released from the three facilities ranged from 160 to 1905 items/g (microplastics/facilities), following in the order of rainwater inspection well > rainwater storage module > rainwater pipe. The particle size of the released microplastics ranged from 3 to 1363 μm, with 10–30 μm accounting for the greatest proportion of particles, 50.10%. The size of microplastics released from the rainwater inspection well and rainwater storage module increased with the aging degree, while the release from the rainwater pipe decreased. The release behavior depends mainly on the composition of the materials and the aging time. Thus, microplastics can be released from plastic rainwater facilities under suitable conditions. The results can be used to further evaluate microplastic pollution caused by urban rainwater facilities.

From bottle to microplastics: Can we estimate how our plastic products are breaking down?

Microplastics (MPs) have become an emerging new pollutant of rising concern due to the exponential growth of plastics in consumer products. Most MP and nanoplastic pollution comes from the fragmentation of plastics through mechanical stress, chemical reactions and biological degradation that occurs during use and after disposal. Models predicting the generation and behavior of MP in the environment are developing, however there is lack of data to predict the rates of MP generation as a function of the abrasive forces. A method to deliver scalable, quantitative release rates of MPs during mechanical stress throughout a plastic's life cycle (e.g., sanding, chewing, river and ocean disposal) is described. A custom abrasion machine was built with features to provide data to calculate power input. The generation rate of MPs through abrasion was tested for the following 3D printed polymers: polylactic acid (PLA), polycarbonate (PC), thermoplastic polyurethane 85A (TPU), polyethylene glycol terephthalate (PETG), high-impact polystyrene (HIPS), and nylon. Each material underwent tensile strength material tests to identify which mechanical properties drive their abrasion rate. Abrasion rate was not observed to correlate to macroscopic mechanic properties. Results indicate that the order of abrasion from most to least were HIPS, nylon, PC, PLA, PETG, and then TPU. This study will help comprehend and provide data to understand generation rates of MPs from consumer plastic products and macro-plastic debris. This will be instrumental in helping to better understand the release of MPs and nanoplastics into the environment and to provide data for fate and transport models, especially in order to predict the amount of plastic entering water systems. MP generation rates and power inputs can be correlated with each plastic's use to inform which release the most MPs and how to better change these products in order to reduce pollution in water sources.

Investigation of microplastics release behavior from ozone-exposed plastic pipe materials

Microplastics (MPs) are detected in drinking water and plastic used during water treatment and distribution is one of the possible sources of MPs. This work aimed to investigate the MPs release behavior from ozone-exposed plastic pipe materials. The changes on physicochemical properties of the plastic materials were analyzed. The carbonyl groups introduction, the oxidation induction time variation, and the surface topography altering were detected after ozone exposure. The MPs release behavior varied between different plastic materials. As the ozone exposure duration of plastic materials prolonged, the released MPs abundance from the materials sharply increased, especially for LDPE, HDPE and PP. PVC was an exception where the released MPs abundance had little changes (p > 0.05). The total released MPs concentration from 20 h-aged samples could be ranked in order as follows: LDPE (656 ± 20 MP L−1) > PP (349 ± 20 MP L−1) > HDPE (337 ± 22 MP L−1) > PVC (63 ± 13 MP L−1). MPs release behavior was more likely to occur for LDPE, which was possibly related to the low oxidation resistance and weak stability of LDPE under ozone exposure. There was a more dominant contribution to MPs abundance increase caused by MPs release from aged plastic pipe materials than secondary MPs generation from original plastic particles. The generated MPs from 20 h-aged LDPE, HDPE, and PP accounted for 88.4%, 82.2%, and 88.3% of the total released MPs, respectively. For ozone-exposed plastic materials, the surface crack propagation and fragmentation posed an entry point for MPs generation. The proportion of generated MPs with polymer composition consistent with pipe materials (PE/PP) increased as the ozone exposure proceeded. Small-sized particles, especially 1–10 μm, were released more predominantly. This study provides an implication that possible MPs release from long-term aged plastic pipe materials under proper conditions could not be ignored.

Prevalence of microplastics in the ocean in Latin America and the Caribbean

The release of microplastics to the ocean is an increasing global environmental concern. The specific characteristics of the Global South (e.g., widespread mismanaged waste and wastewater) make this an even greater challenge. The current study performed a critical review related to the prevalence of microplastics in the ocean in Latin America and the Caribbean, analyzing also the possible sources of microplastics release to the marine environment. A majority of the studies assessed point towards mismanaged waste, inland or offshore, as well as mismanaged wastewater as critical sources of plastic pollution into the ocean. However, there is a need to delve into the effects that these microplastics are generating on local biota and human health.

Characterization of Microplastics Released Based on Polyester Fabric Construction during Washing and Drying.

With the increasing production of synthetic materials, more microplastic fibers are being generated while washing clothes. Consequently, these particles are increasingly detected in the aquatic environment. Synthetic fibers produced via washing have a relatively high contribution to microplastic pollution. Hence, recent research on reducing the release of microplastic fibers is attracting considerable attention. In this study, fabric-specific analysis was performed by strictly controlling various factors, and each washing and drying process was improved by focusing on the mechanical factors affecting microplastic release. Furthermore, the mass of the collected microplastic fibers and their length distribution were measured. Fabric construction, including chemical composition and yarn type, impacted the microplastics released during washing and drying. Differences in the mechanical factors during washing helped to identify the physical factors affecting microplastic release. These results on the release of microplastics may provide a basis for developing a filter system that can minimize the unintended environmental consequences.

The influence of drinking water constituents on the level of microplastic release from plastic kettles

Microplastic (MP) release from household plastic products has become a global concern due to the high recorded levels of microplastic and the direct risk of human exposure. However, the most widely used MP measurement protocol, which involves the use of deionized (DI) water, fails to account for the ions and particles present in real drinking water. In this paper, the influence of typical ions (Ca2+/HCO3-, Fe3+, Cu2+) and particles (Fe2O3 particles) on MP release was systematically investigated by conducting a 100-day study using plastic kettles. Surprisingly, after 40 days, all ions resulted in a greater than 89.0% reduction in MP release while Fe2O3 particles showed no significant effect compared to the DI water control. The MP reduction efficiency ranking is Fe3+ ≈ Cu2+ > Ca2+/HCO3- > > Fe2O3 particles ≈ DI water. Physical and chemical characterization using SEM-EDX, AFM, XPS and Raman spectroscopy confirmed Ca2+/HCO3-, Cu2+ and Fe3+ ions are transformed into passivating films of CaCO3, CuO, and Fe2O3, respectively, which are barriers to MP release. In contrast, there was no film formed when the plastic was exposed to Fe2O3 particles. Studies also confirmed that films with different chemical compositions form naturally in kettles during real life due to the different ions present in local regional water supplies. All films identified in this study can substantially reduce the levels of MP release while withstanding the repeated adverse conditions associated with daily use. This study underscores the potential for regional variations in human MP exposure due to the substantial impact water constituents have on the formation of passivating film formation and the subsequent release of MPs.

Microplastics in the Florence wastewater treatment plant studied by a continuous sampling method and Raman spectroscopy: A preliminary investigation

The presence of an ever increasing amount of plastic in the Italian river system makes it necessary to understand the contribution of their different sources. We focus on the contribution from the wastewater treatment plants to the microplastics (MPs), size less than 5 mm, conveyed to the fluvial system, and on the development of methods for their detection in this matrix.This study, one of the first in Italy, is aimed to investigate the content of MPs present in the effluent of the main wastewater treatment plant in Florence (Italy). We sampled wastewater during dry season to mainly quantify the contribution from civil and municipal activities to the MPs release. The samples were continuously collected over a period of 24 h at the exit of the water line using a series of 8 sieves with different mesh sizes (almost 1000 L filtered volume). The sampled material was analyzed by optical microscopy and micro-Raman spectroscopy by use of low-cost, portable instruments. The spatial resolution of the spectrometer matches the minimum dimension of the mesh size in use (38 μm). The analysis detected an average concentration of 5 MPs per liter in the 38–1000 μm diameter range, corresponding to a daily release of about 35 kg/day into the River Arno, a result in line with other studies carried out on Europe's major rivers. We provide a classification of the polymer composition showing the predominant presence of Polypropylene (29%), Polyethylene (18%) and Polyester (14%). The MP shape classification reveals the relevance of fibers in effluents. The number of sieves used provided an accurate size distribution curve of the sampled MPs allowing to estimate, by extrapolation, a relevant quantity of MPs finer than 38 μm whose determination would otherwise require much more sophisticated methods.

Microplastics in Sewage Sludge: A Known but Underrated Pathway in Wastewater Treatment Plants

Interest in the presence of microplastics (MPs) in wastewater has grown significantly in recent years. In fact, wastewater treatment plants (WWTPs) represent the last barrier before the discharge of MPs into an aquatic ecosystem. The research has highlighted how MPs are in part effectively removed from the waters and accumulated inside the sewage sludge (SeS) produced by the WWTP, being a cause for concern, especially in the case of agricultural reuse. This work aims to analyze the existing literature on the (i) methodical procedure for MPs analysis (thermal, spectroscopic, optical analyses), (ii) qualitative and quantitative presence of MPs in SeS, (iii) effect on sludge properties, and (iv) the possible accumulation in amended soils. Based on the results already obtained in the literature, this work aims to provide critical insights to stimulate interest in the topic and direct future research on aspects that should be deepened. In particular, it emerges that there is a clear need for standardization of the collection methods and the analytical techniques for identifying and quantifying MPs, since their physico-chemical characterization and the study on aging and on the response towards acid or basic pre-treatments are fundamental for the understanding of microplastics ecotoxicological potential.

Release kinetics of microplastics from disposable face masks into the aqueous environment

Disposable face masks are widely used as primary personal protective equipment to control the spread of the SARS-CoV-2 virus. Disposable face masks have been identified as a source of microplastics and a new threat to the environment when improperly handled. To understand the release of microplastics from discarded masks into water, the release quantities of microplastics from three types of disposable face masks (N95, medical surgical, and normal medical masks) were measured within 24 h and their release kinetics were analyzed over seven days. Results showed that polypropylene microplastics fibers and debris of various colors were released. N95 masks released 801 ± 71–2667 ± 97 microplastic particles/(piece·d), medical surgical masks released 1136 ± 87–2343 ± 168 microplastic particles/(piece·d), and normal medical masks released 1034 ± 119–2547 ± 185 microplastic particles/(piece·d), irrespective of the price, weight, or type of mask. The microplastics were first released fast and then slow. The Elovich equation described the release kinetics (R2 > 0.990), and the release rate did not differ with the type of mask. Microplastics of 100–500 μm and of <100 μm were released in large quantities and at rapid rates. Fiber and transparent microplastics accounted for a large proportion of those released, and their daily release proportion increased with time. Fiber microplastics <500 μm in length were predominant in the microplastics released from disposable face masks, indicating that disposable face masks could be a critical source of these in the aqueous environment. There is an urgent need to take action to implement a waste management system limiting the number of masks entering the environment.

Release of Microplastics from Discarded Surgical Masks and Their Adverse Impacts on the Marine Copepod Tigriopus japonicus

Surgical masks (SMs) are the most commonly used personal protective equipment during the COVID-19 pandemic. Due to their vast use and inappropriate disposal worldwide, SMs could potentially cause serious microplastic (MP) pollution in coastal marine environments. This study aimed to investigate the kinetic release of MPs from polypropylene SMs (PP-SMs) in seawater and to evaluate the chronic toxicity of the released MPs to the marine copepod Tigriopus japonicus. On the basis of the results of our kinetic study and available relevant data, we estimated that SMs discarded throughout the year 2020 would lead to >1370 trillion MPs entering the coastal marine environment globally, with a release rate of 396 billion MPs per day. Our results also demonstrated that the copepods ingested the MPs released from PP-SMs, causing a significant decline in their fecundity. The results clearly suggest the MPs released from improperly discarded SMs could have a long-term domino effect on coastal marine ecosystems. To minimize the risk of this emerging threat, better environmental management, policy, and law enforcement for ensuring the proper disposal of SMs are deemed to be necessary.

The aging behaviors and release of microplastics: A review

Microplastics (MPs) have attracted significant concern due to their persistence and adverse effects on organisms. In this review, we summarize the recent literature on the natural and artificial aging process of MPs, and also discuss the associated aging characteristics and mechanisms of MPs. The aged MPs show different morphological and chemical properties from the pristine MPs. Furthermore, to evaluate associated aging effects, the corresponding release of aging process of MPs were systematically evaluated, including the additives and intermediates. Different types of organic pollutants and heavy metals additives are listed. In addition, the release of MPs is affected by environmental factors (i.e., Illumination, salinity, temperature and pH). Aged MPs are more easily absorbed by organisms and have different toxic effects from the pristine MPs. The potential risks of aging MPs and the release of MPs during aging are discussed in detail. This overview provides a direction for further study on the behavior and the toxic effects of MPs in the environment.

Potential microplastic release from beached fishing gear in Great Britain's region of highest fishing litter density

While land-based sources of marine plastic pollution have gained widespread attention, marine-based sources are less extensively investigated. Here, we provide the first in-depth description of abandoned, lost or otherwise discarded fishing gear (ALDFG) on northern and southern beaches of the English Southwest Peninsula, Great Britain's region of highest ALDFG density. Three distinct categories were recorded: twisted rope (0.28 ± 0.14 m−1, 17%), braided rope (0.56 ± 0.28 m−1, 33%) and filament (0.84 ± 0.41 m−1, 50%), which likely correspond to fishing rope, net and line. Estimating the disintegration of ALDFG from length and filament number suggests that it has the potential to generate 1277 ± 431 microplastic pieces m−1, with fishing rope (44%) and net (49%) as the largest emitters. Importantly, ALDFG was over five times more abundant on the south coast, which is likely attributable to the three times higher fishing intensity in that area.