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It has been suggested that the seafloor may be a sink for the plastic debris that enters the ocean. Therefore, the collection of data in the seafloor sediments regarding the co-presence of microplastics (MPs) and contaminants associated to plastic is considered a relevant topic. However, the number of studies addressing their possible correlation in this environment is still limited, and very little is known about the mechanisms that determine the release of plastic additives from plastic items. Starting from this basis, we investigated the presence of MPs and eleven phthalic acid esters (PAEs) in the continental shelf offshore Barcelona. Following a shelf-slope continuum approach, we sampled sediments from five stations, and we performed analysis by means of infrared micro spectroscopy (µFTIR) and liquid chromatography tandem mass spectrometry (LC–MS/MS). MPs were found to range from 62.0 to 931.1 items/kg d.w. with maximum concentration in the submarine canyon Besòs and at the highest depth. Moreover, different trends in the size distribution of fibers and non-fibers were observed, indicating the occurrence of a size dependent selection mechanism during transport and accumulation. PAEs resulted comprised between 1.35 to 2.41 mg/kg with Di(2-ethylhexyl)phthalate (DEHP) the most abundant congeners (1.04 mg/kg). Statistical analysis revealed no correlation between the Σ11PAEs and the total MPs concentration, but correlation between DEHP and fibers (σ = 0.667, p = 0,037), that resulted both correlated to the distance to the coast (ρ = 0.941 with p = 0,008 and ρ = 0.673 with p = 0.035, respectively). [ABSTRACT FROM AUTHOR]

There is strong evidence that the seafloor constitutes a final sink for plastics from land sources. There is also evidence that part of the plastics lying on the shallow seafloor are washed up back to the shoreline. However, little is known on the natural trapping processes leading to such landwards return. Here we investigate microplastics and larger plastic debris within beached seagrass remains including balls (aegagropilae) made of natural aggregates of vegetal fibers intertwined by seawater motion. We found up to 1470 plastic items per kg of plant material, which were mainly composed of negatively buoyant polymer filaments and fibers. Our findings show that seagrass meadows promote plastic debris trapping and aggregation with natural lignocellulosic fibers, which are then ejected and escape the coastal ocean. Our results show how seagrasses, one of the key ecosystems on Earth in terms of provision of goods and services, also counteract marine plastic pollution. In view of our findings, the regression of seagrass meadows in some marine regions acquires a new dimension. [ABSTRACT FROM AUTHOR]

Submarine volcanic eruptions are major catastrophic events that allow investigation of the colonization mechanisms of newly formed seabed. We explored the seafloor after the eruption of the Tagoro submarine volcano off El Hierro Island, Canary Archipelago. Near the summit of the volcanic cone, at about 130 m depth, we found massive mats of long, white filaments that we named Venus's hair. Microscopic and molecular analyses revealed that these filaments are made of bacterial trichomes enveloped within a sheath and colonized by epibiotic bacteria. Metagenomic analyses of the filaments identified a new genus and species of the order Thiotrichales, Thiolava veneris. Venus's hair shows an unprecedented array of metabolic pathways, spanning from the exploitation of organic and inorganic carbon released by volcanic degassing to the uptake of sulfur and nitrogen compounds. This unique metabolic plasticity provides key competitive advantages for the colonization of the new habitat created by the submarine eruption. A specialized and highly diverse food web thrives on the complex three-dimensional habitat formed by these microorganisms, providing evidence that Venus's hair can drive the restart of biological systems after submarine volcanic eruptions.

The global outbreak of the COVID-19 pandemic has given rise to a significant health emergency to adverse impact on environment, and human society. The COVID-19 post-pandemic not only affects human beings but also creates pollution crisis in environment. The post-pandemic situation has shown a drastic change in nature due to biomedical waste load and other components. The inadequate segregation of untreated healthcare wastes, chemical disinfectants, and single-use plastics leads to contamination of the water, air, and agricultural fields. These materials allow the growth of disease-causing agents and transmission. Particularly, the COVID-19 outbreak has posed a severe environmental and health concern in many developing countries for infectious waste. In 2030, plastic enhances a transboundary menace to natural ecological communities and public health. This review provides a complete overview of the COVID-19 pandemic on environmental pollution and its anthropogenic impacts to public health and natural ecosystem considering short- and long-term scenarios. The review thoroughly assesses the impacts on ecosystem in the terrestrial, marine, and atmospheric realms. The information from this evaluation can be utilized to assess the short-term and long-term solutions for minimizing any unfavorable effects. Especially, this topic focuses on the excessive use of plastics and their products, subsequently with the involvement of the scientific community, and policymakers will develop the proper management plan for the upcoming generation. This article also provides crucial research gap knowledge to boost national disaster preparedness in future perspectives. [ABSTRACT FROM AUTHOR]

While many organizations have successfully leveraged big data analytics capabilities to improve their performance, our understanding is limited on whether and how big data analytics capabilities affect social innovation in organizations. Based on the organizational information processing theory and the organizational learning theory, this study aims to investigate how big data analytics capabilities support social innovation, and how knowledge ambidexterity mediates this relationship. A total of 354 high-tech companies in China, this study shows that big data analytics management, big data analytics technology, and big data analytics personnel capabilities all have positive effects on social innovation. In addition, both knowledge exploration and knowledge exploitation play a mediating role in this process. Furthermore, a polynomial regression and response surface analysis shows that social innovation increases when knowledge exploration and knowledge exploitation are highly consistent but declines when knowledge exploration and knowledge exploitation are inconsistent. This study not only provides new perspectives for understanding how big data analytics capabilities contribute to social innovation, complementing the existing literature on big data analytics capabilities and social innovation, but also provides important practical guidance on how organizations can develop big data analytics capabilities to improve social innovation and solve social problems in the digital age. [ABSTRACT FROM AUTHOR]

Microplastic pollution endangers both aquatic and terrestrial ecosystems. Their spread across the food chain also endangers human health. Wastewater treatment plants (WWTPs) can be viewed as the final barrier between microplastics and the environment. In addition, it is well-known that water mites are abundant parasites in aquatic ecosystems, and nearly all insect orders with aquatic stages are considered potential hosts for at least one water mite species. However, no studies have been conducted to test the direct and indirect effects of parasites on population dynamics in freshwater ecosystems or the role of predators in shaping the behavior and life histories of aquatic organisms. Thus, this work aimed to study the seasonal abundance, distribution, composition, and risk assessment of MPs in surface water, aquatic insects (Coroxide and Notonectidae), and for the first time, water mites (Hydrachnidiae), as well as the effect of water mites' parasitism on the number of MPs ingested by aquatic insects in two of the most polluted wastewater sites (S1 and S2) in Sohag Governorate, Egypt. The two wastewater sites receive different wastewater inputs (domestic and industrial). The results showed that the MPs abundance in surface water was higher in S2 than in S1 during the four seasons of the year, where the microplastic abundance in surface water was 2.05 ± 0.79 and 3.01 ± 0.9 particles/L in S1 and S2, respectively. Also, MPs were significantly higher in S2 in two insect taxa (Corixidae and Notonectidae) that are known to be infected by water mites. In contrast, the number of MPs was lower in S1, where water mites were absent. In addition, our results showed that adult water mites accumulated MPs. Overall, the 500–2000 µm size range was the most prevalent for both wastewater sites. Fibers were the most common MP morphotype discovered, followed by fragments. The dominant colors of MP were blue, red, and black. Furthermore, FTIR spectroscopy revealed the existence of three distinct polymers, namely polyester (PES), polypropylene (PP), and polyethylene (PE). To the best of our knowledge, this is the first study to examine the effect of water mites' parasitism on the number of MPs ingested by aquatic organisms. However, Further research is needed to confirm our suggestion. [ABSTRACT FROM AUTHOR]

Background: Wastewater treatment plant outlets are a major source of microplastics, with more than 90% retained in sewage sludge. No standardised method for the extraction, quantification, and characterisation of microplastics in sewage sludge or soil exists, and direct comparison of studies is often impossible. Our aim was to validate oil extraction efficiency with and without pre-treatment with Fenton's reagent of selected microplastics in various types of environmental samples (sewage sludge and organic-rich substrates). Results: Oxidation with Fenton's reagent removed up to 90% of organic material, which improves the recovery rate and made quantification and characterisation easier and more reliable, regardless of type, shape, size, or density of the selected microplastic particles used in this study. Pre-treatment, as a pre-step of the oil extraction method, was shown to be important in reducing organic matter in all environmental samples, including sewage sludge and organic-rich substrates. It also improved the reliability of the selected method, shortened its duration, and, by reducing organic matter, made extracted microplastics more visible. The recovery rate was better for particles 1–5 mm and lower for particles 0.1 < 1 mm. Conclusions: By achieving up to a 100% recovery rate for certain types of microplastics (polypropylene and polystyrene), the selected method proved to be a promising extraction method. It was also shown to be efficient in the organic-rich substrates, for which the characterisation of microplastic particles was done by Fourier transform infrared spectroscopy. The most commonly detected types of microplastics in organic-rich substrates were polyethylene, polypropylene, polystyrene and polyester. [ABSTRACT FROM AUTHOR]

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment. [ABSTRACT FROM AUTHOR]

The MV X-Press Pearl maritime incident had a profound impact on the marine and coastal ecosystems along the west coast of Sri Lanka. Considerable quantities of plastic pellets, specifically nurdles or pellets measuring less than 5 mm and estimated at 1680 tonnes, were released into the Indian Ocean. A notable portion of these plastic pellets/primary microplastics (MPs), has the potential to degrade into secondary MPs. The objective of this study was to investigate and understand the degradation process of plastic pellets into secondary MPs under the extreme conditions of fire and exposure to chemicals during the MV X-Press Pearl maritime disaster. Beach sand samples were collected from 40 locations along the affected west coast of Sri Lanka, at both mean sea level and the berm. An additional 20 samples were collected for a background study covering the entire coastline of Sri Lanka. The Wet Peroxide Oxidation (WPO) process was employed to separate microplastics, and observations of secondary MP quantities were recorded. Fourier Transform Infra-Red Spectroscopic (FTIR) analysis was carried out to identify functional groups of MPs. The variance in average values of secondary MPs at mean sea level (large MPs (i.e. size > 0. 5 mm) = 33 ± 56 items per 1 mm2 and total MPs (i.e. observed through microscope under 40× magnification) = 61 ± 66 items per 1 mm2) and the berm (large = 61 ± 154 items per 1 mm2 and total MPs = 106 ± 165 items per 1 mm2) suggested significant dispersal of large quantities of MPs to other areas in the Indian Ocean with oceanic currents. The baseline average value of secondary total MPs in other coastal areas of the country was approximately 53 ± 66 items per 1 mm2. The positive correlation between large and total secondary MPs and plastic pellets pollution index indicates that a considerable amount of plastic pellets were degraded into secondary MPs within 6 to 8 days after the accident, under the influence of nitric acid and heat/fire. These secondary MPs are mainly composed of low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE), as identified by FTIR observations. Consequently, these lightweight polymers have the potential to spread across a wider region, posing a severe environmental threat on a global scale as a transoceanic marine pollutant. [ABSTRACT FROM AUTHOR]

This article investigates the role of local banking development, per se, in European SME debt policies, using a cross-country dataset. Moreover, it assesses whether the debt policies of SMEs are mainly driven by local or national banking development. We find that higher levels of local banking development increase the amount of debt used by SMEs. Results suggest that national banking institutions reduce the influence of local banking sectors on SME financial behavior. Several robustness and further tests validate our results, suggesting that whilst the process of international integration and digitalization of financial markets, local banking development is still relevant despite the moderating role of national banking policies. Consequently, policy makers should first and foremost allow headquarters and central banks to better support local banks in integrating national banking policies in order to reduce the financial constraints on SMEs and spur their economic growth. [ABSTRACT FROM AUTHOR]

For several laboratory experiments with microplastics, a simple and fast quantification method is advantageous. At the same time, the requirements are often lower compared to microplastic detection from environmental samples. We determined the concentration of non-purgable organic carbon of polystyrene (PS) particles (diameter 0.5, 1, 2, 6 μm) in suspension with known concentrations. Commercially available PS particles were used to test the Total Organic Carbon (TOC) analyzer method for quantifying microplastics in the lower micrometer range under absence of other organic compounds. Addition of iron or aluminum hydroxide to the samples prior to the measurement increased the recovery from 52.9 to 89.7% relative to measurements in the absence of metal hydroxides. With increasing particle size, the recovery in the presence of iron hydroxides decreased from 95.1% at 0.5 μm to 67.1% at 6 μm PS particles and in the presence of aluminum hydroxides from 92.6% at 0.5 μm to 88.9% at 6 μm PS particles. We conclude that metal hydroxides have a catalytic effect on the thermocatalytic oxidation of PS particles and allow a complete conversion to CO2 for a successful quantification of PS particles using a TOC analyzer. Especially for particles larger than 0.5 μm, in the absence of metal hydroxides, the TOC device is not able to fully oxidize the PS particle to CO2 and subsequently detect its concentration. Thus, TOC analysis of PS particles in the presence of metal hydroxides provides a cheap and simple alternative for quantifying microplastic particles in the lower micrometer range for laboratory experiments (e.g. sedimentation studies) where no other organic substances are present. [ABSTRACT FROM AUTHOR]

Noteworthy contributions have highlighted that human contact is a considerable factor in bank-firm relationships. It allows the acquisition of soft information, which alleviates information asymmetries and increases the use of bank debt. The advent of digital technologies in the information collection process open new horizons and change the role of personal contacts in bank-firm interactions, as entrepreneurs visit bank branches less frequently. This study uses a large sample of Italian SMEs from 2011 to 2020 and finds that the rapid increase and use of digital instruments have reduced the positive influence of physical closeness between banks and SMEs on the indebtedness levels. Interestingly, our study has also found that the COVID-19 crisis did not amplify this moderating effect. Results support theories that human contact is an important factor in bank-firm relationships because it allows the acquisition of soft information, which alleviates information asymmetries and increases the use of bank debt. Our study suggests that close human ties are still extremely relevant and digitalization should be exploited to support the collection of the kind of qualitative soft information that is crucial in debt negotiations. Plain English Summary: The growing integration and digitalization of banks gives rise to a question: are local personal bank-entrepreneur relationships still important for small businesses? We interestingly find that human relationships between the bank and the firm occurring at the local level are important in the soft information collection procedures, positively influencing the amount of debt that SMEs use. In light of such relevance, governments' challenge consists on directing banks toward a system that strengthens the collection of soft information in a digitalized world. In a phygital future, digitalization should thus be exploited to provide banks not only quantitative data, but also qualitative information that support lending decisions. [ABSTRACT FROM AUTHOR]

Purpose: The international working group MariLCA has proposed a framework aiming towards integrating the impacts of plastic pollution in life cycle impact assessment (LCIA). Filling one of the identified mechanisms, this paper proposes a harmonized LCIA framework for the development of mechanistic fate factors (FFs) and consequently characterization factors (CFs) for microplastics (MPs) emissions in the marine environment, for the proposed impact category "Physical effects on biota." Methods: Based on a literature review, fate mechanisms and environmental factors influencing MPs in the marine environment are identified. Dominant fate mechanisms are determined, based on which the marine environment is divided into homogeneous sub-compartments. Following on this framework and multimedia fate models adopted in LCIA, rate matrices for different types, shapes, and sizes of MPs are constructed. Fate matrices are obtained by negatively inverting rate matrices. Similar to emission-related impact categories, CF matrices are constructed by multiplying FF matrices with exposure-effect matrices. Results and discussion: The marine environment is divided into marine sub-compartments at two different scales: continental and global. Marine sub-compartments include beach, water surface, water column, and sediments at the continental scale and water surface, water column, and sediments at the global scale. Due to the dependency of MPs fate on their physiology (shape, size, and density), different rate and fate matrices can be obtained. Mechanistic characterization factors for water surface and water column sub-compartments are obtained by multiplying the fate matrix with already existing exposure-effect factors for aquatic ecosystem. However, in order to develop CFs for beach and sediments sub-compartments, this framework suggests the development of new exposure and effect factors specific to these sub-compartments. Conclusion: Since LCA is known as a holistic approach, marine litter should be integrated in its impact assessment. This proposed framework fills one of the gaps of MariLCA's framework that aims towards integrating plastic litter in LCIA by proposing fate and CF matrices for different types of microplastics emitted to the marine environment. [ABSTRACT FROM AUTHOR]

The microplastic body burden of marine animals is often assumed to reflect levels of environmental contamination, yet variations in feeding ecology and regional trait expression could also affect a species’ risk of contaminant uptake. Here, we explore the global inventory of individual microplastic body burden for invertebrate species inhabiting marine sediments across 16 biogeographic provinces. We show that individual microplastic body burden in benthic invertebrates cannot be fully explained by absolute levels of microplastic contamination in the environment, because interspecific differences in behaviour and feeding ecology strongly determine microplastic uptake. Our analyses also indicate a degree of species-specific particle selectivity; likely associated with feeding biology. Highest microplastic burden occurs in the Yellow and Mediterranean Seas and, contrary to expectation, amongst omnivores, predators, and deposit feeders rather than suspension feeding species. Our findings highlight the inadequacy of microplastic uptake risk assessments based on inventories of environmental contamination alone, and the need to understand how species behaviour and trait expression covary with microplastic contamination.Microplastic uptake by animals is often assumed to reflect the level of contamination in the environment. Here, the authors compile a global inventory of individual microplastic body burden in benthic marine invertebrates and find that feeding mode and geographic location are more important predictors than environmental microplastic loading. [ABSTRACT FROM AUTHOR]

After 50 years, the dumping of red mud at the head of Cassidaigne Canyon (Southern France) was stopped in 2015. The area was surveyed in 2021 with an ROV at depths of 440–630 m. Biological findings reported here (images, sampling) have been obtained during a single ROV transect in the heavily impacted zone. In spite of the industrial waste deposit, a diverse faunal assemblage has persisted at the canyon head. Bioconstruction comprising large deep-sea oyster shells, scleractinian corals and hexactinellid sponge skeletons provides elevate and complex substrates for other organisms. Among the more significant findings, three live specimens of Neopycnodonte zibrowii Gofas, C. Salas & Taviani, 2009, previously only known as dead shells in that canyon, were documented and the rarely observed stenopodid shrimp Odontozona edwardsi (Bouvier, 1908) has been sampled (first record in the Mediterranean) and DNA barcoded. [ABSTRACT FROM AUTHOR]

In recent years, microplastics have become an integral part of the terrestrial and aquatic environments, which is one of the major concerns of communities around the world. Therefore, it is necessary to know the current status of studies and feasible potentials in the future. This study, conducted an in-depth bibliometric analysis of publications from 1990 to 2022 to present the influential countries, authors, institutes, papers, and journals on microplastics. Findings reveal that there has been a steady increase in microplastic publications and citations in recent years. And, the number of publications and citations has increased 19 and 35 times since 2015. Besides, we performed a comprehensive keyword analysis to show the significant keywords and clusters in this field. In particular, this study used the TF-IDF method as a text-mining analysis to extract the new keywords used in recent years (i.e., 2020–2022). New keywords can draw the attention of scholars to important issues and provide a basis for future research directions. [ABSTRACT FROM AUTHOR]

Microplastics (<5 mm) pollution is a growing problem affecting coastal communities, marine ecosystems, aquatic life, and human health. The widespread occurrence of marine microplastics, and the need to curb its threats, require expansive, and continuous monitoring. While microplastic research has increased in recent years and generated significant volumes of data, there is a lack of a robust, open access, and long-term aggregation of this data. The National Oceanic and Atmospheric Administration (NOAA) National Centers for Environmental Information (NCEI) now provides a global open access to marine microplastics data on an easily discoverable and accessible GIS web map and data portal (https://www.ncei.noaa.gov/products/microplastics). The objective of this data portal is to develop a repository where microplastics data are aggregated, archived, and served in a user friendly, consistent, and reliable manner. This work contributes to NCEI's efforts towards data standardization, integration, harmonization, and interoperability among national and international collaborators for monitoring global marine microplastics. This paper describes the NOAA NCEI global marine microplastics database, its creation, quality control procedures, and future directions. [ABSTRACT FROM AUTHOR]

Mismanaged plastic waste is a significant contributor to microplastic pollution in the environment, which can cause riverine pollution problems, adverse ecological effects, and pose risks to human health. In this context, extensive research has been conducted on microplastics (MPs) contamination in surface water in urban water environments. This work detected the abundance and characteristics of MPs in urban canals and sub-river (Mark-Hiao River) in the Vientiane capital. Additionally, the hazard risk to the ecological system posed by MPs was analyzed using calculated risk index values. The results showed that the abundance of MPs in the dry and rainy seasons ranged from 0.38 to 4.61 items/m3 and 1.23 to 7.10 items/m3, respectively. Among them, the most commonly found microplastic polymer types in the water samples were polypropylene (PP) > polyethylene (PE) > polystyrene > polyethylene terephthalate (PET) > nylon > other plastic. The diverse composition of MPs along the canals and Mark-Hiao River indicated medium and low hazard levels. However, it is necessary to take action to mitigate and manage the potential risks caused by microplastic pollution, ensuring the preservation of urban aquatic environment for future generations. Strategies recommended encompass promoting publicity and education, implementing green consumption practices, formulating and efficiently implementing regulations, improving the efficiency of wastewater treatment plant, encouraging the use of biodegradable plastics, refusing single-use and non-degradable plastics, and setting a monitoring standard. [ABSTRACT FROM AUTHOR]

As an important source of microplastics, the water ecological risk of tire wear particles (TWPs) has attracted widespread attention worldwide. However, the occurrence and behavior of TWPs and their biological effects in water environments have not been clearly analyzed. For example, most contemporary studies have focused on the evaluation of the aquatic toxicity of TWPs leachate, and little attention has been paid to the behavior process and potential risks of its surface properties in water environments. In addition, most studies rely on preparing TWPs under laboratory conditions or purchasing commercial TWPs for studying their water environmental behavior or exposure. These obviously cannot meet the requirements of accurate assessment of water ecological risks of TWPs. As thus, in addition to describing the occurrence, distribution, and (aging) transformation of TWPs in different water environments, we further tried to explain the potential water environment behavior process and multiple pathways leading to potential adverse impacts of TWPs on aquatic organisms from the perspectives of particle self-toxicity and release toxicity, as well as synergistic effects of TWPs and other substances are also discussed. The existing data, such as studies on the self-characteristics of TWPs, environmental factors, and subjects, are insufficient to comprehensively evaluate the recent changes in essential water ecosystem services and multifunctions caused by TWPs, implying that the impact of TWPs on water environmental health needs to be further evaluated, and the corresponding countermeasures should be recommended. In this context, the current review provides an outlook on future research on TWPs in aquatic environments. [ABSTRACT FROM AUTHOR]

The pollution of microplastics (MPs) is a worldwide major concern, as they have become a major part of our food chain. MPs enter our ecosystem via different pathways, including anthropogenic activities and improper disposal of plastics. The aim of this article is to review the current scientific literature related to MPs and how they affect different life forms on earth. Briefly, MPs induced negative effects on humans are primarily linked with the oxidative stress and disruption in immunity. MPs not only affect the soil chemical and physical properties such as reduction in soil health and productivity but also impose harmful effects on soil microorganisms. Moreover, MP-induced plant growth reduction results from three complementary mechanisms: (i) reduction in root and shoot growth, (ii) reduction in photosynthesis accompanied by higher reactive oxygen species (ROS) production, and (iii) reduction in nutrient uptake via altered root growth. Given the negative effects of MPs on different life forms, it is important to remove or remediate them. We have discussed different MP removal methods including coagulation, membrane filtration technology, biochar, and biological degradation of MPs in soil and wastewater effluents. The use of ozone as ultrafiltration technique has also been shown as the most promising technique for MP removal. Finally, some future research recommendations are also put forward at the end to further enhance our understanding of the MPs induced negative effects on different life forms. The flowchart shows the interaction of MPs from water contaminated with MPs with different parts of the ecosystem and final interaction with human health [ABSTRACT FROM AUTHOR]

Plastic particles smaller than 5 mm are microplastics. They are among the significant pollutants that recently attracted attention. Great quantities of microplastics enter the sewage system daily and reach wastewater treatment plants (WWTPs). As a result, WWTPs are potential microplastic sources. Hence, they create a pathway for microplastics to reach aquatic environments with treated wastewater discharge. Studies on microplastic characterization in WWTPs have gained momentum in academia. This study investigates the abundance, size, shape, color, polymer type, and removal efficiencies of microplastics in a municipal wastewater treatment plant (WWTP) in Denizli/Turkey. The results showed that the dominant microplastic shape in wastewater samples was fibers (41.78%–60.77%) in the 100–500 µm (58.57%–80.07%) size range. Most of the microplastics were transparent-white (32.86%–58.93%). The dominant polymer types were polyethylene (54.05%) and polyethylene vinyl acetate (37.84%) in raw wastewater. Furthermore, the microplastic removal efficiencies of the Denizli Central WWTP as a whole and for individual treatment units were evaluated. Although the microplastic pollution removal efficiency of the Denizli Central WWTP was over 95%, the microplastic concentration discharged daily into the receiving environment was considerably high (1.28 × 1010 MP/d). Thus, Denizli Central WWTP effluents result in a high volume of emissions in terms of microplastic pollution with a significant daily discharge to the Çürüksu Stream. [ABSTRACT FROM AUTHOR]

Coronavirus Pandemic is the current biggest challenge against humanity. Apart from the personal health issues and higher mortality by the coronavirus, recent research works have also reported the environmental impacts of the pandemic. The review aims to analyze the current status of face masks and personal protective equipment littering and subsequent environmental impact in terms of microplastic and microfiber pollution. Recent researches in this domain are collected from the leading databases with relevant keywords and critically analyzed. The review results report a multi-fold increment in the usage of personal protective equipment, particularly face masks after the pandemic. Mismanagement of these items leads them to reach the marine environment through a variety of transportation. The results show a significant amount of increment in plastic and pandemic-related littering after the pandemic. The systematic review shows that the use of synthetic fibers in disposable personal protective equipment and masks leads to release of fibers that can add-on to microfiber pollution. The results are also true in the case of reusable masks as the repeated laundry and disinfection methods release a significantly higher amount of microfibers. Only very few studies have addressed the release of microfiber from the mask, and no studies have reported the impact of personal protective equipment. The worldwide mass adaptation and improper disposal of these materials increase the seriousness of the problem multiple folds. These findings suggest the immediate requirement of critical analysis of the pandemic-related littering and microfiber release characteristics. The research also urges the need for the implementation of an environmental management plan as a mitigation strategy around the globe. [ABSTRACT FROM AUTHOR]

In this study, the abundance of microplastics (MPs) in the Uppanar and Gadilam estuaries in Cuddalore, on the southeast coast of India, is reported. In the estuarine sediments, MP abundance ranged from 36.3 ± 3.39 to 51.6 ± 2.05 particles/Kg dw. Different types of MP shapes, such as fibers (41.7–47.9%), films (21.2–27.2%), and fragments (18.3–25.5%) were observed in the size range of 100–1000 µm. Diverse colours of MPs were observed, among which red (30.1–34.5%) was predominantly noticed in the estuarine sediments. Six polymers were identified by µ-FTIR, among which LDPE (39%) and PP (35%) were dominant. MPs pollution in these estuaries is composed of domestic, industrial, and fishing wastes. Risk assessments show that the area falls under hazard categories I to III, indicating low to high risk. This study improves knowledge on MPs contamination in Uppanar and Gadilam estuaries and provides impetus for further research to identify the actual sources and impacts of MPs on aquatic systems along the east coast of India. [ABSTRACT FROM AUTHOR]

The total mass of individual synthetic polymers present as microplastic (MP < 2 mm) pollutants in the sediments of interconnected aquatic environments was determined adopting the Polymer Identification and Specific Analysis (PISA) procedure. The investigated area includes a coastal lakebed (Massaciuccoli), a coastal seabed (Serchio River estuarine), and a sandy beach (Lecciona), all within a natural park area in Tuscany (Italy). Polyolefins, poly(styrene) (PS), poly(vinyl chloride) (PVC), polycarbonate (PC), poly(ethylene terephthalate) (PET), and the polyamides poly(caprolactame) (Nylon 6) and poly(hexamethylene adipamide) (Nylon 6,6) were fractionated and quantified through a sequence of selective solvent extractions followed by either analytical pyrolysis or reversed-phase HPLC analysis of the products of hydrolytic depolymerizations under acidic and alkaline conditions. The highest concentrations of polyolefins (highly degraded, up to 864 µg/kg of dry sediment) and PS (up to 1138 µg/kg) MPs were found in the beach dune sector, where larger plastic debris are not removed by the cyclic swash action and are thus prone to further aging and fragmentation. Surprisingly, low concentrations of less degraded polyolefins (around 30 µg/kg) were found throughout the transect zones of the beach. Positive correlation was found between polar polymers (PVC, PC) and phthalates, most likely absorbed from polluted environments. PET and nylons above their respective LOQ values were found in the lakebed and estuarine seabed hot spots. The pollution levels suggest a significant contribution from riverine and canalized surface waters collecting urban (treated) wastewaters and waters from Serchio River and the much larger Arno River aquifers, characterized by a high anthropogenic pressure. [ABSTRACT FROM AUTHOR]

Microplastic pollution in aquatic ecosystems presents an emerging environmental threat that can have adverse effects on ecology, endanger aquatic species, and result in economic damage. Despite the numerous studies reporting the presence of microplastics in marine environments, research into their presence in freshwater systems or inland waters remains limited. This study aimed to assess the level of microplastic pollution transported by the Munzur and Pülümür Rivers and some small rivers that flow into the Uzunçayır dam lake, which is the confluence of the Munzur and Pülümür Rivers in Türkiye. Samples were collected from 23 stations, with the concentration of microplastics ranging from 0.01 MP/m3 at P-4 station to 28.21 MP/m3 at P-10, a station located near a city. Microplastics comprise four types: fiber, film, fragment, and glitter. The average size of microplastics was 1.46 ± 0.05 mm, with the average size of fibers, films, fragments, and glitter-type microplastics being 1.58 ± 0.07 mm, 1.23 ± 0.10 mm, 1.21 ± 0.11 mm, and 0.78 ± 0.16 mm, respectively. The most frequent polymers were polyethylene (31.8%), polystyrene (21.1%), and polypropylene (10.5%). Despite being considered remote and less populated rivers compared to other river systems in Türkiye, all sampling sites showed varying concentrations of microplastics. [ABSTRACT FROM AUTHOR]

A sediment trap experiment was conducted at a depth of 750 m at the mouth of Tokyo Bay to clarify the quantity and transport process of particles from the bay to the open ocean. The high total mass flux (8.7 ± 4.5 g m–2 d–1) suggests that the particles not only originate in the surface layer right above the trap, but are also focused in Uraga Channel and discharged into the bay mouth. The organic carbon and nitrogen isotope ratios (δ13Corg, δ15N) of the trapped particles were like those of the surface sediment in the bay, that is, a mixture of particles in rivers and suspended particles in the surface layer of the bay. Compared with the results of the experiment conducted in 1995–2002, the average total mass flux was reduced by 70% and organic carbon content was reduced by 50%. The δ13Corg values of trapped particles were also lower than those observed in the previous experiment, indicating a lower contribution from surface-suspended particles with high δ13Corg values in the bay. These results could partly reflect a decrease of the concentration of the suspended particulate carbon in the bay by half over 20 years. Another factor contributing to the decrease of the flux at the bay mouth would be that the intrusion of Kuroshio coastal water into the bay, which pushes particles out to the bay mouth, has not occurred in recent years. [ABSTRACT FROM AUTHOR]

Ocean mining activities have been ongoing for nearly 70 years, making great contributions to industrialization. Given the increasing demand for energy, along with the restructuring of the energy supply catalyzed by efforts to achieve a low-carbon economy, deep seabed mining will play an important role in addressing energy- and resource-related problems in the future. However, deep seabed mining remains in the exploratory stage, with many challenges presented by the high-pressure, low-temperature, and complex geologic and hydrodynamic environments in deep-sea mining areas, which are inaccessible to human activities. Thus, considerable efforts are required to ensure sustainable, economic, reliable, and safe deep seabed mining. This study reviews the latest advances in marine engineering geology and the environment related to deep-sea mining activities, presents a bibliometric analysis of the development of ocean mineral resources since the 1950s, summarizes the development, theory, and issues related to techniques for the three stages of ocean mining (i.e., exploration, extraction, and closure), and discusses the engineering geology environment, geological disasters, in-situ monitoring techniques, environmental protection requirements, and environmental effects in detail. Finally, this paper gives some key conclusions and future perspectives to provide insights for subsequent studies and commercial mining operations. [ABSTRACT FROM AUTHOR]

The marine environment is affected by the increasing presence of microplastics (MPs; < 5 mm), and the seafloor acts as a sink for these particles. Locations with different predominant seafloor habitat and protection level applied were selected from Cabrera Marine-Terrestrial National Park (henceforth, Cabrera MPA) (western Mediterranean Sea) with the aim to assess the distribution of MPs along the sediments of this Mediterranean MPA. A total of 37 samples were collected. A high diversity of sediment between locations was detected according to the Udden-Wentworth classification and locations were clustered into two main groups according to the predominance of different particle size fractions. The identification of MPs was carried out according to the sediment particle size classification. A total of 1431 MPs and a mean value (± SD) of 314.53 ± 409.94 items kg−1 D.W. were identified, and 70% of the particles were fibers. Statistically higher abundances of MPs were found in sediments collected from sandy habitats, with a mean value of 630.80 ± 636.87 items kg−1 D.W., compared to the abundances of MPs found in locations with different predominant seafloor habitats, that ranged from 136.79 ± 156.33 items kg−1 D.W. in habitats with similar predominance of seagrass and sand to 223.02 ± 113.35 items kg−1 D.W. in habitats with similar predominance of rocks and sand. The abundance of MPs regarding each sediment particle size fraction differed between years and locations, and the abundance of MPs according to each identified shape differed between sampling years, particle size fraction, and predominant seafloor habitat. The present study highlights the ubiquitous presence of MPs in seafloor sediments from a MPA. Furthermore, the results suggest that the predominant seafloor habitat can modulate the presence of MPs in marine environments in both general abundances and shape of items. [ABSTRACT FROM AUTHOR]

Currently research on microplastics in the environment focuses on non-degradable microplastics with little attention to research on degradable microplastics. This study involved a 400-day experiment in a simulated lake environment of three degradable microplastics, poly(ε-caprolactone) (PCL), polybutylene succinate (PBS), and poly(butylene adipate terephthalate) (PBAT) at the sediment water interface. Results showed that (1) for the three microplastics, Cd concentration showed a large change from 0 to 20 mm in the water above the sediment interface; the adsorption of Cd, Pb, and Cu in a diffusive gradients thin film (DGT) device are the highest in PBAT micro plastic, followed by PCL and then PBS. (2) Diffuse flux (J) of the three degradable microplastics indicated that Cu, Cd, and Pb in the sediments come from the overlying water that was added to the simulation experiment. (3) Fourier transform infra-red spectroscopy (FTIR) for investigating the adsorption capacity of Cu, Cd, and Pb in the three degradable microplastics showed the absorption peak intensity increased and widened, and some adsorption sites changed. (4) Correlation analysis showed that the factors which most influenced diffusion flux for both water and sediments are oxidation–reduction potential (ORP), followed by organic matter (OM), pH, and electrical conductivity (EC). [ABSTRACT FROM AUTHOR]

A comprehensive understanding of the concentration of microplastics (MPs) in seawaters is essential to implement monitoring programs and understand the impacts on ecosystems, as required by the European legislation to protect the marine environment. In this context, the purpose of this study is to investigate the composition, quantity, and spatial distribution of microplastics from coastal to offshore areas in three Italian seawaters. In addition, the distribution of microplastics between surface and subsurface water layers was analyzed in order to better understand the dynamics of MPs in the upper layers of the water column. A total number of 6069 MPs (mean total concentration of 0.029 microplastics · m−2) were found to be heterogeneous in type, shape, and color. In general, MPs concentrations decrease with coastal distance, except when environmental forcings are predominant (such as sea currents). Moreover, the amount of surface MPs was almost four times that of subsurface microplastics, which consisted mostly of fibers. In light of these results, it becomes clear how critical it is to plan remediation actions and programs to minimize microplastic accumulations in the sea. [ABSTRACT FROM AUTHOR]

Aegagropiles are conglomerations of fibre debris from Posidonia oceanica meadows that are frequently found along Mediterranean beaches, but the plant organ from which these fibres arise remains unknown. In this study, a histological comparison of P. oceanica organs from 3 shoots with the structure of aegagropile fibres showed that most of them arise from leaf sheaths and rhizomes, suggesting that they are degradation products from the "matte" rather than from the leaf litter, which is mainly composed of detached leaf blades. Moreover, fungal hyphae, micro-sclerotia and typical degradation traces were found in the peripheral tissues of living P. oceanica organs, as well as in degrading aegagropiles. We assume, by comparing Vohník's observations and the observations made in this study, that these endophytic fungi and degradation traces might be attributed to a dark septate endophyte (DSE) in the Aigialaceae (Pleosporales), Posidoniomyces atricolor, which was recently described as an endosymbiont in P. oceanica roots. It constitutes one of the most important microorganisms by abundance that degrade P. oceanica tissues within the matte and give rise to the different fibre types in aegagropiles. This study shows that the proliferation of fungi causes organ degradation in Posidonia, starting early in living P. oceanica plants, continuing in the matte and, probably, in the leaf litter. The DSE plays a much more important role than that of a simple plant endosymbiont; its omnipresence within P. oceanica (and the degradation of the middle lamella and cell death during proliferation) causing the degradation of various Posidonia organs also contributes to the enrichment of the 'matte' compartment of this ecosystem, notably favouring nitrogen retention in its chitinous walls. [ABSTRACT FROM AUTHOR]

Plastic pollution is a big source of concern around the world. Research to date has focused on the types of plastic in the environment and the processing of plastic waste. For policymakers and consumers to be informed decision makers, they need to understand the industries which use plastics and the plastic intensity of those industries. Using input–output data for the USA, we calculate the plastic intensity (the value of plastic inputs per dollar of output) of 415 non-plastic industries for 13 types of plastic. We find the most plastic intensive industries are related to clothing and fabric manufacturing. This is true for aggregate plastics as well as plastics most likely to contribute to pollution. The high plastic intensity of the clothing and fabric industries is consistent with the abundance of clothing-related microplastics found in waterways. The results indicate that policies focused on consumer-facing plastics such as plastic bags do not address key plastic pollution pathways, and can help policymakers and consumers make decisions that improve environmental outcomes. [ABSTRACT FROM AUTHOR]

This study analyzed the diversity and abundance of diatom frustules including the ancillary parameters using the core top sediments from five locations (21, 19, 15, 13, and 11°N) along the central Arabian Sea (64°E), an area profoundly influenced by atmospheric forcing (monsoons) and oxygen minimum zone (OMZ) with high spatial variability. Significantly higher organic carbon (0.97 ± 0.05%) and diatom frustules (5.92 ± 0.57 × 104 valves g−1) were noticed in the north (21, 19, 15°N) where natural nutrient enrichment via open-ocean upwelling, winter convection, and lateral advection support large diatom-dominated phytoplankton blooms and intense OMZ. Conversely, the south (13, 11°N) depicted significantly lower organic carbon (0.74 ± 0.08%) as well as frustules (4.02 ± 0.87 × 104 valves g−1) as this area mostly remains nutrient-poor dominated by small-medium-sized phytoplankton. The north was dominated by large-sized diatoms like Coscinodiscus that could escape grazing and sink consequently due to higher ballasting. Furthermore, the presence of the intense OMZ in the north might reduce grazing pressure (low zooplankton stock) and mineralization speed facilitating higher phytodetritus transport. Relatively smaller chain-forming centric (Thalassiosira) and pennate diatoms (Pseudo-nitzschia, Fragilaria, Nitzschia, etc.) were found throughout the transect with higher abundance in the south. The euphotic diatom diversity from the existing literature was compared with the frustule diversity from the sediments suggesting not all diatoms make their way to the abyss. Such distinct spatial north–south variability in diatom frustule size as well as abundance could be attributed to cell size, grazing, and water column mineralization rates related to OMZ. [ABSTRACT FROM AUTHOR]

Sewage treatment plant (STP) acts as a potential source of microplastic contamination in the environment. The presence of microplastics in the sewage treatment plant is reported over the globe in varying concentrations. Hence, the current study is intended to evaluate the presence and abundance of microplastics occurring in sewage treatment plants in India. The samples were processed through digestion and density separation, followed by microscopic and polymer identification through Fourier transform infrared spectroscopy. Also, different wastewater parameters were studied to analyze their influence. High microplastic concentrations were detected in the influent (1860 ± 265 MPs/L), which reduced by > 90%, to around 148 ± 51 MPs/L in the effluent. The concentration of microplastics in sewage sludge was 830 MPs/kg. The prominent plastic types identified include low-density polyethylene, polypropylene, polyurethane, polyvinyl chloride, and rayon. The smaller particles prevail in the effluent, releasing around 30 billion particles per day to the environment. This suggests that the current STP is efficient in removing the majority of the particles, but considerations are needed to avoid the ecological risks associated. [ABSTRACT FROM AUTHOR]

Background: Since the Covid-19 pandemic in 2019, the use of plastics has increased exponentially, so it is imperative to manage and dispose of these plastic wastes safely. Objectives: This review focuses on the management strategies governed by the policies of each country to reduce plastic waste through physical collection methods and methods that use eco-imitation technologies. Results: Thus far, physical treatment methods have been applied to sewage and drinking water treatment. The abilities of bio-inspired treatment methods are being assessed in terms of capturing microplastics (MPs) and nanoplastics (NPs), extracting substances from marine organisms, reducing toxicity, and developing alternatives to petroleum-based plastics. Conclusions: Various post-treatment methods have been proposed to collect and remove MPs and NPs that have reached into aquatic ecosystems and subsequently reduce their toxicity. However, there are limitations that the effectiveness of these methods is hindered by the lack of policies governing the entire process of plastic use before the post-treatment. Purpose of Review: We purpose to reduce plastic waste through methods that use eco-imitation technologies. Recent Findings: These eco-imitation methods are attracting attention as viable future plastic waste treatment options in line with the goals of sustainable development. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are emerging pollutants of widespread concern in aquatic environments. The aim of this study was to evaluate the negative impact of pristine MPs of polystyrene of 100 μm on embryo and larvae of Danio rerio exposed to three environmentally relevant concentrations of polystyrene (3.84 × 10− 6, 3.84 × 10− 7, and 3.84 × 10− 8 g/mL). The exposure effect was evaluated through the general morphology score, biometrics, and integrated biomarker response version 2 index. No mortality was observed but the anatomical structure of fishes was affected showing pigmentation deficiency and alterations in the head region as the main affected endpoints. The general morphology score and the integrated biomarker response values were highly sensitive to address the effect of the three concentrations of MPs used here. Our results provide solid evidence of the negative impact of 100 μm pristine polystyrene MPs exposure on early stages of zebrafish. [ABSTRACT FROM AUTHOR]

The omnipresence of microplastics (MPs) in marine and terrestrial environments as a pollutant of concern is well established and widely discussed in the literature. However, studies on MP contamination in commercial food sources like salts from the terrestrial environment are scarce. Thus, this is the first study to investigate various varieties of Australian commercial salts (both terrestrial and marine salts) as a source of MPs in the human diet, and the first to detect MPs in black salt. Using Nile red dye, the MPs were detected and counted under light microscopy, further characterised using attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR) and scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM–EDS). Of all the 90 suspected particles, 78.8% were identified as MPs with a size ranging between 23.2 µm and 3.9 mm. The fibres and fragments constituted 75.78% and 24.22% respectively. Among the tested samples, Himalayan pink salt (coarse) from terrestrial sources was found to have the highest MP load, i.e. 174.04 ± 25.05 (SD) particle/kg, followed by black salt at 157.41 ± 23.13 particle/kg. The average concentration of detected MPs in Australian commercial salts is 85.19 ± 63.04 (SD) per kg. Polyamide (33.8%) and polyurethane (30.98%) were the dominant MP types. Considering the maximum recommended (World Health Organization) salt uptake by adults daily at 5 g, we interpret that an average person living in Australia may be ingesting approximately 155.47 MPs/year from salt uptake. Overall, MP contamination was higher in terrestrial salts (such as black and Himalayan salt) than the marine salt. In conclusion, we highlight those commercial salts used in our daily lives serve as sources of MPs in the diet, with unknown effects on human health. [ABSTRACT FROM AUTHOR]

Submarine groundwater discharge (SGD) is the groundwater flow from land to the sea across the seabed, and it includes both terrane freshwater and recirculated seawater in the sub-surface. This review (i) systematically evaluates findings of various quantification methodologies, (ii) examines the estimated SGD in scientific publications between 2000 and 2020, and (iii) quantitatively evaluates current situation of coastal zone management through the bibliometric analysis of research papers. Apart from enhancing the shortage of groundwater resources in coastal area, the SGD brings nutrients (nitrate and phosphate), toxic heavy metals, and organic compounds, and thus contaminate the seawater. Therefore, the improved understanding about location and quantity of global SGD is essential to conserve the coastal and ocean ecosystems. [ABSTRACT FROM AUTHOR]

The use of citizen science in the collection of surface water marine microplastics (MP) samples with manta trawl was tested in the Baltic Sea, where the collection of surface water samples is often hampered by environmental conditions. Sampling was carried out at 7 locations around the Baltic Sea with a custom-made manta trawl which was operated onboard a sailing boat. The total concentrations of ≥ 0.3 mm MP in the samples ranged from 0.45 to 1.98 MP m−3. Based on the results and experiences from this study, citizen science could be introduced into the toolbox of monitoring large MP. When the common basic constraints of surface water sampling within a regional sea are defined and agreed upon, citizen science could be used for strengthening the power of assessments on the state of the marine environment by increasing the spatial coverage of the monitored area. [ABSTRACT FROM AUTHOR]

The bamboo coral Isidella elongata is a forest-forming alcyonacean that dwells on deep-sea soft bottoms and is presently found in the Otranto Channel (Southern Adriatic Sea). In this study, we explored the spatial distribution and the demographic structure of the I. elongata facies (IF) over time, along with the diversity of IF-associated fauna in the southern Adriatic Sea, by using a time-series data of 9 years (2012–2020) from the Mediterranean International Bottom Trawl Survey (MEDITS). The spatial distribution of I. elongata was confronted with the fishing effort in the study area over time. This facies showed a constant spatial extent but a decreasing biomass over time. Changes in the basal diameter distribution of the colonies were also observed, with a significant decrease in the sizes from 2014 to 2020. These results suggest an increasing fishery-related impact from a developing deep-sea fishery occurring in the study area. The bamboo coral in the study area represents a hotspot of biodiversity in the context of the bathyal environment. A fisheries-restricted area was recently proposed in the context of the General Fisheries Commission for the Mediterranean at the Otranto Channel to help the conservation of I. elongata in the southern Adriatic Sea. [ABSTRACT FROM AUTHOR]

A high-throughput approach to detecting, quantifying, and characterizing microplastics (MPs) by shape, size, and polymer type using laser direct infrared (LDIR) spectroscopy in surface water samples is demonstrated. Three urban creeks were sampled for their MP content near Cincinnati, OH. A simple Fenton reaction was used to oxidize the surface water samples, and the water samples were filtered onto a gold-coated polyester membrane. Infrared (IR) analysis for polymer identification was conducted, with recoveries of 88.3% ± 1.2%. This method was able to quantify MPs down to a diameter of 20 µm, a size comparable to that of MPs quantified by other techniques such as Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. A shape-classifying algorithm was designed using the aspect ratio values of particles to categorize MPs as fibers, fibrous fragments, fragments, spherical fragments, or spheres. Cut-off values were identified from measurements of known sphere, fragment, and fibrous particles. About half of all environmental samples were classified as fragments while the other shapes accounted for the other half. A cut-off hit quality index (HQI) value of 0.7 was used to classify known and unidentified particles based on spectral matches to a reference library. Center for Marine Debris Research Polymer Kit 1.0 standards were analyzed by LDIR and compared to the given FTIR spectra by HQI, showing that LDIR obtains similar identifications as FTIR analysis. The simplicity and automation of the LDIR allows for quick, reproducible particle analysis, making LDIR attractive for high-throughput analysis of MPs. [ABSTRACT FROM AUTHOR]

In this paper, we investigated seasonal variations in concentrations of microplastics (MPs) in surface sediments of a lagoon heavily impacted by human activities, located in northern Tunisia (the Bizerte lagoon, southern Mediterranean Sea). Analyses of 112 sediment samples collected from 28 stations between May 2019 and February 2020 revealed significant seasonal variation in concentrations of total MPs, with the highest levels recorded in August 2019 (109.6 ± 59.8 items kg−1 DS (dry sediment)) and the lowest in February 2020 (33.2 ± 22.0 items kg−1 DS). In terms of polymer types, polyethylene particles were the most abundant throughout the year, followed by polypropylene, polyvinyl chloride, and polyethylene terephthalate. Spatial variations in total MP concentrations were found to depend on several environmental factors, including proximity to the coastline, level of anthropogenic pressure, location inside the lagoon, and presence/absence of vegetation. The upper 5-cm surface sediment layer of the lagoon was found to contain ~ 9.96 × 1010 MP particles, equal to ~ 248.97 t of plastic. Similar patterns of microplastic composition and structure were found throughout the year, revealing the same plastic pollution hotspots during all seasons. This indicates that sources of plastic pollution are land-based and originate from coastal urban, industrial, and agricultural areas, as well as from major freshwater streams. The findings of the present work can help to develop an efficient environmental management plan aiming to reduce and/or stop the spread of plastic pollution and its impacts on the socially and economically important ecosystem of the Bizerte lagoon. [ABSTRACT FROM AUTHOR]

Industrial wastewater, domestic wastewater, and stormwater are the three entry points for microplastics (MP) in wastewater treatment plants. Extreme weather conditions, such as rising temperatures and heavy rainfall caused by climate change, can alter the rate at which MP enters wastewater treatment plants. In this study, wastewater and sludge samples from different treatment stages were collected during a 12-month sampling campaign (seasonal) to determine the efficiency of a municipal wastewater treatment plant in removing microplastic particles. MP ranging from 20 to 1000 µm were detected and classified by shape, color, size, and chemical composition. All samples contained MP particles, with concentration ranging from 1964 ± 50–2982 ± 54 MP/L in influent to 744 ± 13–1244 ± 21 MP/L in effluent and 91.1 ± 8–61.9 ± 5 MP/g in sludge; 71.6–90.1% identified particles were fragment-type with black, white, and transparent colors. Most of the microplastic particles were removed in the activated sludge tank, while the average removal rate in the wastewater treatment plant was 57%. The total concentration of MP was 27% higher in spring than in other seasons. The most common microplastic particles were polyethylene terephthalate (PET), polystyrene (PS), and polypropylene (PP). These results demonstrate the value of long-term monitoring and MP quantification, which would provide a more accurate estimate of MP pollution from wastewater treatment plants. [ABSTRACT FROM AUTHOR]

The accumulation and fragmentation of plastics in water sources is one of the important problems of recent times. In this study, it was aimed to determine and characterize the microplastic accumulation in the sediment and in the stomach and gills of the freshwater crayfish Astacus leptodactylus (Eschscholtz 1823) in Durusu (Terkos) Lake, which is one of the most important water resources of Istanbul and even the Marmara Region. Thus, the microplastic contamination of both the lake sediment and crayfish was revealed for the first time in Turkey, and insight was given into the transmission of this contamination to the biota. The microplastic amount of the sediment samples was found as 32.26–396.71 pieces.kg−1 dry sediment. The microplastic amount was determined as 0.89–15.67 pieces.ind−1 in stomach content and 0.5–19.67 pieces.ind−1 in the gills of the crayfish. The predominant microplastic types were found as fragments in the sediment samples, fibers in the gill, and stomach content. As a result of the analysis, the main polymers identified in crayfish samples were polypropylene (78%) and followed by polyphenylene sulfide (11%) and polyethylene (11%); in sediment samples, polypropylene (47%) and followed by polyvinyl alcohol (20%), polyethylene (20%), and polyamide (13%). Activities carried out in the coastal area pollute the lake, and it is necessary to control the anthropogenic and fisheries-related pollution in the lake. [ABSTRACT FROM AUTHOR]

Purpose: The pervasive use of plastics, coupled with inadequate waste management systems in many countries, has led to widespread leakage of plastics into the environment. In South Africa, the predominant type of shopping bags are single-use plastic bags; but paper, biodegradable plastic and re-usable bags have emerged as alternatives. To compare these alternatives in terms of environmental impacts across the whole product life cycle, we carried out a cradle-to-grave life cycle assessment (LCA) of 16 shopping bag types available in South Africa. Methods: The comparison includes single-use plastic, bioplastic and paper bags, as well as re-usable bags (typically made from plastic in South Africa). The functional unit was based on the estimated annual volume of groceries purchased per capita. An attributional LCA was carried out using the ReCiPe 2016 Midpoint(H) method, with 18 mid-point impact categories. In addition, given the lack of an impact category for plastic pollution in existing methods, we developed a mid-point indicator based on the persistence of plastics (and other materials) leaked to the environment (Persistence of leaked material, PersistenceLM). Specific attention was placed on modelling end-of-life and waste management in the South African context. Economic-based allocation at the point of substitution was used to apportion environmental impacts to virgin and recyclate material, and the production of recyclate was modelled using system expansion. Results and discussion: Re-usable bag types, specifically the 70 µm High Density Polyethylene (HDPE) and non-woven Polyester bags, had the lowest environmental impacts for all indicators, except PersistenceLM. Paper and biodegradable plastic bags had a lower PersistenceLM impact as compared to the petro-based plastic bags, and therefore may be preferable in terms of avoiding plastics accumulating in the environment. The re-usable bags need to be used at least 3 to 10 times to offer lower environmental impacts than single-use ones. Among the single-use bags, biodegradable bags made from imported Polybutylene Adipate Terepthalate (PBAT) plus starch showed the lowest environmental impacts across all impact categories, including PersistenceLM, followed by the Paper bag. The single-use 24 µm HDPE bag (HDPE_24) with no recycled content had the highest overall environmental impacts, while increasing the recycled content reduced overall environmental impacts by up to 52%. Compared to other countries, the high environmental impacts of plastic bags in South Africa can largely be attributed to the coal-to-liquids process used for polymer production, which is intensive in terms of both energy and raw materials. [ABSTRACT FROM AUTHOR]

Microplastic pollution has been considered as a global environmental issue that potentially threatens human health. However, research about microplastic pollution in urban rivers is still insufficient. This study analyzed the abundance and distribution of microplastics in surface water of the Nanfei River in Hefei, China. Microplastic concentrations ranged from 0.8 to 27 items/L along the studied river. The small size (50–333 μm) (47.58–84.89%) and white (55.65–88.89%) were predominant among all samples, except that collected from the source reach. Pellet was a typical and abundant microplastic type and accounted for 60.30%. PE and PP were the major polymers, occupying 55.24% and 22.86%, respectively. The results showed that traditional environmental management practices including salvaging surface garbage regularly and setting wooden suspended crossbars at tributary confluences could significantly mitigate the pollution degree of microplastics. The polymer risk index was calculated to describe the potential risk of microplastics, and the pollution level was still at high risk under various management practices. This study provides a valuable finding for future research on microplastics in urban city rivers, which may improve the knowledge that how to control and prevent microplastic pollution. [ABSTRACT FROM AUTHOR]