Microplastic Emissions Research Articles

Optimizing Fish Feed Pellets Handling Systems to Minimize Microplastics Emissions - A Pilot Test Based Approach

The fisheries and aquaculture industries are vital components of global food production, yet they also contribute to release of microplastics into marine environments, posing risks to ecosystem health and seafood safety. Among the contributing factors, the erosion of feeding pipes during the pneumatic conveyance of fish feed pellets stands out as a significant source of microplastic pollution. This study focuses on optimizing feed pellet conveying systems in fish farms to minimize microplastic emissions while maximizing pipeline lifespan and pellet integrity. Using high-density polyethylene (HDPE) pipes commonly found in aquaculture facilities, the impact of air velocity and pipeline configuration on pipe wall erosion and pellet breakage was investigated. Through pneumatic conveying tests, the effects of varying air flow rates and bend radii were assessed on pipeline wear and feed pellet integrity. The findings of the study underscored the importance of optimizing operating parameters to bring a balance between preventing pipe blockages and minimizing abrasive impacts on pellets and pipeline surfaces. Furthermore, a simulationbased approach to optimize feeding system performance is presented, integrating the experimental results into a computational model. This model allows for the evaluation of different operating conditions and pipeline configurations, offering insights into costeffective strategies for reducing microplastic emissions while maintaining efficient feed delivery to fish populations. Ultimately, this research provided practical recommendations and best practices for the aquaculture industry to mitigate microplastic pollution from feeding pipes. By optimizing feed pellet conveying systems, environmental sustainability can be enhanced, seafood quality be preserved, and bolster consumer confidence in aquaculture products.

Assessment of microplastics in the sediments around Hywind Scotland Offshore Wind Farm

Abstract Leading edge erosion of turbine blades is hypothesized to be a source of microplastic (MP; 1-5000 µm) emissions from offshore wind farms (OWFs) to the marine environment. Given the higher density of rotor blade coating and leading-edge protection (LEP) materials than seawater, released MP are expected to enter the surrounding waters and sink to the sediments, where the highest concentrations may be expected in the sediments in and around the OWF infrastructure. Here, we present a methodological approach for the quantification and characterisation of coating and LEP MPs (>300 µm) in sediments, applied to samples collected from 15 locations around the Hywind Scotland floating OWF. To validate the approach, reference materials were produced from the different coating layers and LEP material and used to generate library IR spectra and mass spectra so that such particles could be robustly identified if present in the sediment samples. The reference materials were also used to evaluate particle integrity and recovery across the sample preparation applied to real samples (ZnCl2 density separation, filtration). Results suggested the LEP material was unaffected by the sample processing, but fragmentation was observed for the two coating layers studied, leading to an increase in the number of particles and a decrease in weight due to loss of particles <300 µm. After isolation, particles were evaluated using microscopy and suspected MP particles were identified and subjected to a detailed chemical characterisation by Fourier transform infrared spectroscopy (FTIR). In the field samples, twenty particles were confirmed as MP, but none had polymer compositions matching the coatings and LEP materials, instead representing common thermoplastics in the form of flakes, films, fragments, and filaments.

Atmospheric Microplastics Emission Source Potentials and Deposition Patterns in Semi‐Arid Croplands of Northern China

AbstractFrequent wind erosion events in semi‐arid regions can lead to significant atmospheric microplastic (MP) emissions from croplands. We examine observed and predicted characteristics of atmospheric MPs over cropland in Northern China. Measurements showed that fibers were the predominant morphology, accounting for 69% of the 198 observed MPs. The observed atmospheric MP abundance varied widely, averaging 0.088 # m−3 in the absence of air masses passing through near‐surface croplands and increasing significantly to 0.26 # m−3 when such air masses were present. The predictions of deposition flux for atmospheric MPs over croplands indicated a spatial variation ranging from less than 0.5 g km−2 day−1 in the north to over 15 g km−2 day−1 in the south, corresponding to an average of approximately 13.3 g km−2 day−1. Our findings highlight the dual role of surface soil as both a potential source and sink of atmospheric MPs, underscoring the need for further research on the regional dynamics of wind‐driven MP emissions and their associated ecosystem health risks in semi‐arid croplands.

Evaluating microplastic emission from takeaway containers: A Micro-Raman approach across diverse exposure scenarios

Based on inconsistencies observed in literature regarding microplastic levels released by takeaway plastic containers, this study investigates the release from takeaway containers composed of polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET). To simulate real-world conditions, experiments were conducted using Milli-Q water at room temperature, 100 °C, and at pH 4.5. Containers were subjected to 20-min exposure with agitation, and microplastics were quantified via optical microscopy, with micro-Raman spectroscopy to confirm the particle polymeric nature. The results indicate that PET and PS containers released microplastic in varying quantities: 9 and 1 at room temperature, 7 and 3 in acidified water, and 17 and 30 at 100 °C, respectively. The particle sizes ranged between 13 and 32 μm. Notably, no microplastics were detected from PP containers under any tested conditions. This study underscores the significant release of microplastics from PET and PS containers, particularly at elevated temperatures, suggesting that PP may represent a safer alternative.

Long-Term Monitoring of Microplastics in a German Municipal Wastewater Treatment Plant

Wastewater treatment plants (WWTPs) have been identified as important point sources for microplastics (MPs) in the environment; monitoring MP emissions in the WWTP effluent is therefore essential for contamination control. The aim of this study is to acquire a large number of samples (320) over a period of two years and three months to determine the temporal variations in microplastic contamination in the outlet of the municipal WWTP Landau-Mörlheim. The effluent of the third cleaning stage is sampled with a 10 µm filter cartridge, processed in the laboratory using a hydrogen peroxide treatment, and MPs are then detected by fluorescence staining. The results show high temporal variations in the microplastic concentrations in the effluent of the WWTP. This indicates that high numbers of samples are necessary to obtain a representative assessment of the microplastic emissions; single samples are not representative. The average microplastic concentration in the effluent was 27.8 ± 29.8 MP/L, ranging from 0.6 MP/L to 194.0 MP/L. This leads to a yearly emission of 1.5 × 1011 MP for the WWTP Landau-Mörlheim, corresponding to an emission of 2.8 × 106 MP/inhabitant and year. Statistically significant seasonal variations could not be observed, although there is a trend towards lower MP concentrations in summer. Further, no correlations with other wastewater or weather parameters could be found.

Comparative Analysis of Face Mask Usage and Environmental Impact in Asian Cities during and after the COVID-19 Pandemic

The COVID-19 pandemic has led to a surge in face mask demand, resulting in increased face mask waste and environmental impacts. This study investigates mask usage patterns and the environmental impacts of single-use and cloth masks across three phases: pre-COVID-19, COVID-19, and the new normal. A comprehensive survey conducted in five cities across four Asian countries reveals a surge in mask usage during COVID-19 (6.81 pieces/week), followed by a decline in the new normal (3.73 pieces/week), though usage remained higher than pre-COVID-19 levels (1.46 pieces/week). For single-use masks, age significantly impacts usage in all cities, while gender and education level affect usage in Shanghai, Harbin, and Depok. Household income influences mask use in Shanghai and Harbin. For cloth masks, education level significantly correlates with usage in most cities. The study highlights the significant environmental impact of mask use, particularly in densely populated urban areas. Switching to cloth masks for one year could reduce carbon footprints by 44.27–81.9 million kgCO2eq, decrease solid waste by 34.81–52.41 million kg, and reduce microplastic emissions by 6.50 to 15.56 trillion particles in the first 24 h after disposal. However, this transition may increase water usage by 1.73–1.86 billion m3H2Oeq. The study also offers policy recommendations on mask usage and disposal.

Potential deterioration of chemical water quality due to trace metal adsorption onto tire and road wear particles – Environmentally representative experiments

Tire wear particles are an increasing issue in particle emissions to the environment. Germany-wide approximately 100,000 t tire wear particles are emitted every year into the environment which are estimated to be one third of the microplastic emissions. Up to 20% are estimated to reach inland surface waters. Their behavior in the aquatic environment is understudied. Tire wear particles have an overly hydrophobic surface that is capable of adsorbing substances like trace elements. In this study we investigated the adsorption and desorption of trace metals onto and from the particle surface of tire-related samples in water samples of the Freiberger Mulde, a river with naturally elevated concentration of trace elements. The priority trace metals Cr, Ni, Zn, Cd and Pb show a significant adsorption onto the particle surface of tire-related samples. Tire wear particles themselves revealed adsorption of mainly Ni, Cd and Pb. Regarding the German classification for suspended matter in freshwaters, an endangering of the chemical water quality is expected due to the adsorption process and not due to the particles themselves. Upcoming electromobility is expected to increase the Zn (increased tire abrasion) and decrease the Cu amount (reduced brake abrasion) released to freshwaters.

The Pollution Characteristics and Fate of Microplastics in Typical Wastewater Treatment Systems in Northern China

This study focuses on the occurrence status and removal efficiency of microplastics in wastewater treatment plant processes. Analysis of effluent and sludge samples from the Wulongkou and Shuangqiao wastewater treatment plants in Zhengzhou revealed an overall microplastic removal efficiency of 95.64% and 92.53%, respectively, indicating the effectiveness of wastewater treatment plants in reducing microplastic emissions. Microplastics primarily exist in forms such as fiber, fragment, floc, film, and grain. Fibers are predominant in the effluent of the Wulongkou plant, while fibers and films predominate in the effluent of the Shuangqiao plant. Moreover, microplastics are predominantly sized below 500 μm, with larger microplastics (2–5 mm) exhibiting higher removal efficiencies after secondary treatment. Analysis of microplastic types revealed that PE is the most common type in the effluent of the Wulongkou plant, while the Shuangqiao plant predominantly contains PE and PA66. The abundance of microplastics in sludge samples was found to be 6.4 ± 0.8 items/g and 11.3 ± 2.3 items/g, highlighting sludge as an important sink for microplastics. Surface analysis of microplastics revealed characteristics such as wrinkles and cracks, with energy-dispersive spectroscopy indicating significant adsorption of heavy metal elements such as Zn, Hg, and Pb onto microplastic surfaces in sludge. These findings underscore the importance of microplastic removal in wastewater treatment processes and provide scientific evidence for the control and management of microplastic pollution in the future.

People's attitudes regarding plastics and microplastics pollution: Perceptions, behaviors, and policy implications

Evidence of microplastics has been found in a variety of marine ecosystems, terrestrial ecosystems, animal species, and sometimes even humans. There is a growing consensus that plastics and microplastics pose a threat to human health and food safety, both in terms of the environment and the food chain. Yet, there is currently no technically viable option for addressing the problem of microplastics in the environment. Understanding people's preferences is therefore critical for minimizing plastics and microplastics contamination. This study employed the ordered logistic regression model to examine the people’s readiness to restrict microplastic pollutions and its influencing elements, as well as their attitudes, perceptions and behaviors concerning plastics and microplastics. Face-to-face interviews were conducted at random, resulting in a total of 465 acceptable questionnaires. The findings expose a concerning lack of awareness about microplastics, as only 22% of respondents possessed prior knowledge, and a notable 66% remained uninformed about microplastics pollution. The desire to minimize microplastics emission was substantially influenced by a variety of factors, including family size, occupation, gender, familiarity with plastics and microplastics related to the health concerns and the environment. Gender differences become evident, with women exhibiting greater willingness than men to mitigate microplastics emission, and environmental practitioners displaying heightened motivation. Familiarity with plastics and microplastics particles enhanced the possibility that respondents would take action to reduce microplastics pollution. The study concludes by offering a number of policy reforms and legislative changes that would limit microplastics contamination during the plastic production and recycling processes.

Quantifying annual microplastic emissions of an urban catchment: Surface runoff vs wastewater sources

Urban clusters are recognized as hotspots of microplastic pollution, and the associated urban rivers convey microplastics into the global oceans. Despite this knowledge, the relative contributions of various sources to the annual microplastic emissions from urban catchments remain scarcely quantified. Here, we quantified microplastic emissions from a riverine urban catchment in Japan. The total microplastics (size range: 10–5000 μm) released from the catchment amounted to 269.1 tons/annum, of which 78.1% is contributed by surface runoff and other uncontrolled emissions (UCE), and 21.1% emerges from the regulated wastewater (controlled emissions; CE), implying that approximately one-fifth is intercepted and removed by the wastewater treatment plants (WWTPs). This further indicated higher microplastic pollution by unmanaged surface runoff compared to untreated wastewater. In the dry season, WWTPs contributed significantly to the reduction of total microplastic emissions (95%) compared to wet periods (8%). On an annual scale, the treated effluent occupies only 0.1% of the total microplastics released to the river network (212.4 tons/annum), while the remaining portion is dominated by UCE, i.e., primarily surface runoff emissions (98.9%), and trivially by the background microplastic inputs that are potentially derived through atmospheric depositions in dry days (1.0%). It was shown that moderate and heavy rainfall events which occur during 18% of the year (within the context of Japan), leading to 95% of the annual microplastic emissions, are crucial for pollution control of urban rivers. Furthermore, our study demonstrated that surface area-normalized microplastic emissions from an urban catchment (∼0.8 tons/km2/annum) is globally relevant, especially for planning microplastic interventions for developed cities.

A Comparison of new and age-old approaches treating microplastics in the marine environment

In recent years, microplastic pollution in the ocean has become a new environmental threat, posing a serious potential threat to marine ecology. Due to its high degradation resistance and bioaccumulation, it is an urgent and critical issue for the environment. Unfortunately, current technologies for removing, recycling, or degrading microplastics are not sufficient to eliminate them. The main sources of microplastics (MPs) in the ocean are ocean drift inputs, river inputs, fishing and shipping activities, microplastic emissions from human settlements, and atmospheric migration. Microplastics may pose a threat to marine life and affect the stability of marine ecosystems. Therefore, it is urgent to further study governance methods and analysis processes, and strengthen the source control of marine microplastic pollution. This study aims to analyze and discuss different methods for treating marine microplastics, analyze their respective advantages and limitations, and evaluate their feasibility and effectiveness in practical applications. The study ultimately emphasized the importance of effective management of marine microplastics, which is crucial for protecting marine ecosystems and human health. Through a comprehensive analysis of physical, chemical, and biological methods, this study provides valuable insights for marine environmental management and research institutions, thereby promoting the development and application of effective management technologies to achieve sustainable environmental outcomes.

Microplastic Emission from Soil-Air Interface

Microplastic Emission from Soil-Air Interface

A new approach from public behavioral attitudes and perceptions towards microplastics: Influencing factors, and policy proposals

This research paper addresses the urgent environmental concern of microplastic (MP) emissions, focusing on the behavioral attitudes and perceptions of the general populace in Shyamnagar Upazila, Bangladesh. Against the backdrop of escalating MP pollution globally, this study investigates the level of awareness and the factors influencing public engagement in mitigating MP prevalence. Leveraging survey data from 350 respondents, the ordered logistic regression (OLR) and boosted regression tree (BRT) models are employed for comprehensive data analysis. The findings expose a concerning lack of awareness about MPs, as only 12% of respondents possessed prior knowledge, and a notable 63% remained uninformed about MP pollution. The OLR model reveals a positive correlation between heightened awareness of MPs and an increased willingness to take action. Gender differences become evident, with women exhibiting greater willingness than men to mitigate MP emissions, and environmental practitioners displaying heightened motivation. The BRT model underscores construction materials and industrial pollution as the primary influential factors amplifying MP pollution. These insights not only illuminate the existing scenario but also provide a basis for fostering favorable behavioral attitudes and perceptions to mitigate the prevalence of MPs within the coastal milieu.

Microplastics in personal care products and cosmetics in Sri Lanka

In the Sri Lankan context, the lack of baseline studies to mitigate microplastic emissions through personal care and cosmetic products poses a huge problem. Hence this study serves as the first scientific investigation to analyze and characterize microplastics in selected personal care and cosmetic items available in the Sri Lankan markets. Fifteen brands representing five categories (face wash, facial scrubs, baby creams, shaving creams, and skin creams) of personal care and cosmetic items served as the basis for this investigation. Based on a questionnaire survey, from each category, three highly utilized brands were chosen and triplicates from each brand were used for the analysis. All samples were treated with the Fenton reagent to extract microplastics. Then through Nile red staining suspected microplastic were screened and characterized through FT-IR spectroscopy. The Nile Red analysis revealed seven brands of the fifteen to be stained with Nile Red and demonstrate luminance properties under UV light. However, FT-IR analysis proved only six brands contained actual microplastics. Low-density polyethylene and ethylene-propylene copolymer were the dominant types of microplastic. Most microplastics were irregularly shaped and white in color with sizes ranging from 238.55 ± 50.74 to 450.69 ± 174.9 μm. An emission estimation revealed that products FS-01 and FW-03 contain 3.36 ± 0.20 g and 0.2 ± 0.05 g of isolatable microplastics per product. While the present study provides scientific evidence for the availability of microplastics in products in Sri Lankan markets, it also provides a great opportunity to develop relevant policies and regulations to control them.

Ceramic membranes as a potential high-performance alternative to microplastic filters for household washing machines

The development of effective, commercially available microplastic filters has become more important due to the steady increase in microplastic emissions from laundry washing cycles and the stringent regulations enforced in many countries. In this present study, commercially available microplastic filters and alternative membranes were thoroughly investigated with real laundry wastewater based on their microplastic filterability and organic contaminant retention. The microplastic filterability of each filter and membrane was assessed using a fluid imaging microscopy device, known as FlowCam, which is recognized for its rapid and realistic quantification. As a result, commercially available microplastic filters revealed a poor microplastic filtering performance, with a removal efficiency of only 19.7–24.8%, with no retention of organic contaminants. A subsequent systematic comparison of polymeric and ceramic membranes with smaller pores was thus conducted to explore their potential as effective alternative microplastic filters for household washing machines. While both membranes effectively retained microplastic fibers and organic contaminants, the ceramic membrane exhibited lower susceptibly to fouling due to its relatively hydrophobic surface. Additionally, it also removed a significant proportion of hydrophobic compounds from real laundry wastewater, thereby improving its organic retention. Further research into the convenient cleaning, long-term sustainability, and practical design of mountable ceramic membranes is necessary before their widespread adoption as external washing machine filters.

Are vehicle tires major contributors to microplastic emissions into the China seas? A simple model perspective

Microplastics pose a substantial threat to our environment. Given China's large population and rapid economic growth, it is urgent to estimate the annual emissions of microplastics into its marine environment. The microplastics show a significant variation in their source emissions as well as in their physical and chemical properties, leading to differences in their transport and fate in aquatic environments. To account for these variations, we developed a process-oriented model that considers microplastics from different sources and the inter-provincial variation in their retention rate to assess annual microplastic emissions into the China seas. On a national scale, of the microplastics emitted, 36.05 % are from household laundry activities, 27.26 % are from the wear and tear of vehicle tires, and 24.04 % are from the abrasion of plastic household items. After emission, 60.21 % are removed by wastewater treatment plants. The overall proportion of microplastics that end up in the marine environment highly depends on the specific riverine retention rate of microplastics from vehicle tires. Including the high settling rate of these microplastics, this proportion drops from 9.96 % to 3.29 %, rendering vehicle tires a minor contributor to microplastic emissions into the China seas compared to other sources. Moreover, when using the density-dependent approach and considering the east/west dimension of each province, the microplastic emissions from vehicle tires into the China seas decrease from 71 % to 5.27 %. This underscores the urgent need for global and regional models to account for the detailed riverine transport process of microplastics from vehicle tires in order to enhance the accuracy of their emission estimates into coastal waters.

Reduction of Microplastic in Wastewater Via Electrocoagulation Process

In recent years, microplastic has become an emerging contaminant that has endangered the ecosystem and public health. This environmental issue has been discovered in the atmosphere, soil, and water bodies. These sources of pollutants can be either primary or secondary. The primary sources of microplastic are the clothing and cosmetic industry, plastic manufacturing plants, fishing businesses, shipping lines, sewage treatment plants, car tires and air blasting. Moreover, microplastic emission from secondary sources involves degrading large plastic particles to smaller elements under mechanical fragmentation and ultraviolet. Microplastic can be defined as plastic particles of different shapes that are less than 5mm. It can be denoted that this microplastic has been detected in the wastewater effluent and needs to be sufficiently removed from the conventional methods. Therefore, this research aims to determine the reduction rate of microplastic in wastewater via the electrocoagulation process. The wastewater effluent was taken from the wastewater treatment plant, Universiti Teknologi MARA Campus Dengkil. The characteristics of the wastewater effluent have been determined for biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia-nitrogen, total suspended solids (TSS), turbidity and E.coli. The microplastic employed in the experiment was polystyrene (PS). A duration of 60 and 120 minutes were taken to reduce the PS. Additionally, the analysis using Fourier-transform infrared spectroscopy (FTIR) has been done to observe the chemical structure of the PS polymer. The results showed that the maximum percentage of reduction for COD was 100%, TSS with a value of 80%, ammonia-nitrogen of 98% and turbidity of 46%. Besides, the removal of PS has achieved 82% using this technique. It can be found that electrocoagulation can be a promising method for reducing the microplastic in the water environment, especially in the wastewater treatment plant.

The Unseen Threat: Microplastic Emissions from Face Masks and Limited Public Awareness

The Unseen Threat: Microplastic Emissions from Face Masks and Limited Public Awareness

Microplastic emissions via air and compost from an industrial composting facility in England

ABSTRACT Composting provides a sustainable method of processing biodegradable waste but is often contaminated with plastic. We quantified and characterised microplastics in air and compost samples from an industrial aerobic green waste composting facility in England. Compost samples were taken at different stages of the process; air samples were taken onsite, upwind, and downwind. Microplastics were found in compost from all stages of the process at levels comparable to those reported for marine sediments; higher concentrations were found in the screening stages of the composting process (mean 9.0 (IQR: 7.1) and 9.0 (IQR: 7.4) MPs 5 g-1 (dw), for 30 mm and 10 mm screened material, respectively). Airborne microplastics were found onsite (32–49 MP m−3), upwind (1 MP m−3) and downwind (3 MP m−3). Composting facilities represent a potential source of microplastics and point of entry to the wider environment. Further investigation into other sites and processes is warranted.

Microplastic occurrence during the pre-treatment of polypropylene in a simulated washing process for mechanical recycling

AbstractIn this study, the micro-plastic emission during polypropylene washing was investigated. Washing post-consumer waste before the re-granulation step is an important process to remove contaminants on the waste material which can interfere with downstream processing and product quality. To simulate a pre-treatment step during mechanical recycling, an industrial washing machine with two different temperatures (30 °C and 60 °C) and residence times (5 min and 15 min) was used. The whole washing effluent was filtered, gravimetrically quantified and with DSC measurements qualitatively identified. Results suggest a release of micro-plastics during washing whereby the residence time has about a two-fold higher impact on possible emissions than temperature. Graphical abstract