Plastic pollution solutions: emerging technologies to prevent and collectmarineplastic pollution

Biodegradation: the best solution to the world problem of discarded polymers

The widespread use of polymers has made our lives increasingly convenient by offering a more convenient and dependable material. However, the challenge of efficiently decomposing these materials has resulted in a surge of polymer waste, posing environment and health risk. Currently, landfill and incineration treatment approaches have notable shortcomings, prompting a shift towards more eco-friendly and sustainable biodegradation approaches. Biodegradation primarily relies on microorganisms, with research focusing on both solitary bacterial strain and multi-strain communities for polymer biodegradation. Furthermore, directed evolution and rational design of enzyme have significantly contributed to the polymer biodegradation process. However, previous reviews often undervaluing the role of multi-strain communities. In this review, we assess the current state of these three significant fields of research, provide practical solutions to issues with polymer biodegradation, and outline potential future directions for the subject. Ultimately, biodegradation, whether facilitated by single bacteria, multi-strain communities, or engineered enzymes, now represents the most effective method for managing waste polymers.

Rethinking plastic entrapment: Misconceptions and implications for ecosystem services in coastal habitats

This study addresses the pressing issue of plastic pollution in coastal and marine ecosystems, challenging the misconception that the entrapment of plastics can be considered as an ecosystem service. We differentiate between essential natural processes that sustain ecological balance and biodiversity and the detrimental accumulation of synthetic polymers. The pathways through which plastics enter these environments-from terrestrial to maritime sources-are examined, alongside their pervasive impacts on crucial ecosystem services such as habitat quality, the vitality of marine species, and nutrient cycling. Our findings highlight the paradox of resilience and vulnerability in these ecosystems: while capable of accumulating substantial amounts of plastic debris, they suffer long-lasting ecological, socio-economic, and health repercussions. We argue for a paradigm shift in management strategies aimed at reducing plastic production at the source, improving waste management practices, conducting targeted cleanup operations, and rehabilitating impacted ecosystems. Emphasizing a comprehensive understanding of plastic pollution is vital for framing effective solutions and necessitates a reevaluation of societal, industrial, and regulatory frameworks. This shift is imperative not only to address current pollution levels but also to safeguard and sustain the functionality of coastal ecosystems, ensuring their ability to continue providing essential services and supporting biodiversity.

Eco-friendly approaches for mitigating plastic pollution: advancements and implications for a greener future

Plastic pollution has become a global problem since the extensive use of plastic in industries such as packaging, electronics, manufacturing and construction, healthcare, transportation, and others. This has resulted in an environmental burden that is continually growing, which has inspired many scientists as well as environmentalists to come up with creative solutions to deal with this problem. Numerous studies have been reviewed to determine practical, affordable, and environmentally friendly solutions to regulate plastic waste by leveraging microbes' innate abilities to naturally decompose polymers. Enzymatic breakdown of plastics has been proposed to serve this goal since the discovery of enzymes from microbial sources that truly interact with plastic in its naturalistic environment and because it is a much faster and more effective method than others. The scope of diverse microbes and associated enzymes in polymer breakdown is highlighted in the current review. The use of co-cultures or microbial consortium-based techniques for the improved breakdown of plastic products and the generation of high-value end products that may be utilized as prototypes of bioenergy sources is highlighted. The review also offers a thorough overview of the developments in the microbiological and enzymatic biological degradation of plastics, as well as several elements that impact this process for the survival of our planet.

Tide of change: Urgency of a national marine litter policy in India

The rise of plastics in the 20th century revolutionized modern life but inadvertently exacerbated the marine litter crisis. The proliferation of wastes such as single-use plastics has escalated pollution along the coastline, demanding coordinated, decisive, and unified action. While the absence of specific national marine litter policies is concerning, there is growing recognition of urgency to address this issue. A group of experts and stakeholders was involved through a multi-staged workshop to assess the generated information based on scientific evidence and formulate a framework for the National Marine Litter Policy (NMLP). This paper proposes policy options (4 targets & 20 strategies) to address marine litter pollution, especially plastics, and aims to elucidate the urgency and significance of implementing an NMLP as a comprehensive strategy to combat plastics pollution. Implementing dedicated policies and action plans tailored to the unique challenges faced by each country is a vital step towards sustainable oceans.

Microplastics in Ghana: An in-depth review of research, environmental threats, sources, and impacts on ecosystems and human health

Microplastics pose significant challenges on a global scale. In Ghana, these tiny pollutants infiltrate diverse ecosystems such as coastal areas, rivers, lakes, and forests, vital to the nation's economy and social well-being. This review examines the current depth of knowledge in research and the escalating concern of microplastics, identifying significant gaps in research and understanding. The findings highlight the limited understanding of the extent and distribution of microplastic pollution across different environmental compartments, primarily focusing on coastal environments. Additionally, detection and quantification techniques for microplastics face several complexities and limitations in the Ghanaian context due to constraints such as infrastructure, resources, and expertise. Despite some research efforts, particularly along the coastline, there is still a distinct lack of attention in various regions and ecosystems within Ghana. This imbalance in research focus hinders the understanding and effective mitigation of microplastics in the country. This therefore necessitates the implementation of systematic policy frameworks, emphasizing the importance of recycling and upcycling as effective strategies to address the challenges of microplastics in Ghana with more targeted research and public engagement. This review serves as a call to action for a strategic approach to research and policy-making on microplastic research and pollution in Ghana.

Poly(butylene oxalate-co-terephthalate): A PBAT-like but rapid hydrolytic degradation plastic

Concerns over worldwide plastic pollution have led to the development of biodegradable polyester materials with excellent physical and chemical properties through the copolymerization of poly(butylene oxalate) (PBOx). As a result, poly(butylene oxalate-co-terephthalate)s (PBOTs) with varying compositions, were prepared by incorporating aromatic units. Studies have indicated that PBOT-47 (with a 47% molar terephthalate), exhibits exceptional mechanical properties. With an elongation at break of 1160% and a tensile strength that remains above 30 MPa, similar to or even better than those of the commercial biodegradable plastic poly(butylene adipate-co-terephthalate) PBAT-47 (47% molar terephthalate). Moreover, the permeability coefficients of PBAT-47 for H2O, CO2 and O2 were 5.8, 50.6 and 5.6 times higher than that of PBOT-47, revealing the superior barrier properties of PBOT. Through experimental research and theoretical simulation, the mechanism of the copolymer hydrolysis was elucidated. The readily hydrolytic nature of the oxalate unit endows it with the capacity for rapid degradation, possessing the potential to be a short-term degradable material with physical properties similar to PBAT.

Fragmented marine plastics as the prevalent litter type on a small island beach in the Adriatic

The issue of plastic pollution has dramatically intensified in the recent years. Our study investigates extensive plastic contamination of a sandy beach on a small Adriatic island. The beach was sampled on three occasions, in 2013, 2020 and 2022, using 1 m2 quadrats placed along the lower and upper strandlines, resulting in average litter concentrations of 385 ± 106, 1095 ± 522 and 129 ± 37 item m-2, respectively. The lower size limit of collected litter was 1 mm, thus including large microplastics. Plastic fragments (49-74 %) and plastic pellets (15 %-37 %) were predominant litter categories. The proportion of fragments is significantly higher during the tourist season with a more intensive cleaning regime (April-October), as opposed to the off-season (November-March). Fisheries and aquaculture litter was identified as a relevant source of pollution. More research is needed in the future into the microplastics smaller than 1 mm.

Where the rubber meets the road: Emerging environmental impacts of tire wear particles and their chemical cocktails

About 3 billion new tires are produced each year and about 800 million tires become waste annually. Global dependence upon tires produced from natural rubber and petroleum-based compounds represents a persistent and complex environmental problem with only partial and often-times, ineffective solutions. Tire emissions may be in the form of whole tires, tire particles, and chemical compounds, each of which is transported through various atmospheric, terrestrial, and aquatic routes in the natural and built environments. Production and use of tires generates multiple heavy metals, plastics, PAH's, and other compounds that can be toxic alone or as chemical cocktails. Used tires require storage space, are energy intensive to recycle, and generally have few post-wear uses that are not also potential sources of pollutants (e.g., crumb rubber, pavements, burning). Tire particles emitted during use are a major component of microplastics in urban runoff and a source of unique and highly potent toxic substances. Thus, tires represent a ubiquitous and complex pollutant that requires a comprehensive examination to develop effective management and remediation. We approach the issue of tire pollution holistically by examining the life cycle of tires across production, emissions, recycling, and disposal. In this paper, we synthesize recent research and data about the environmental and human health risks associated with the production, use, and disposal of tires and discuss gaps in our knowledge about fate and transport, as well as the toxicology of tire particles and chemical leachates. We examine potential management and remediation approaches for addressing exposure risks across the life cycle of tires. We consider tires as pollutants across three levels: tires in their whole state, as particulates, and as a mixture of chemical cocktails. Finally, we discuss information gaps in our understanding of tires as a pollutant and outline key questions to improve our knowledge and ability to manage and remediate tire pollution.

White tides: The plastic nurdles problem

The proliferation of plastic pollution, particularly from nurdles (small plastic pellets used in manufacturing), poses significant environmental and ecological risks. Originating with the invention of Bakelite in 1907 and escalating post-World War II with advanced petrochemical technologies, nurdles are the second largest source of primary microplastic pollution globally. Each year an estimated 445,970 tonnes of nurdles enter the environment worldwide. Nurdle spills, such as those along Spain's Galician coast and other global incidents, underline the need for improved spill response, preventive measures, and international regulatory coordination. The environmental impact of nurdles, compared to more visible oil spills, is insidious and long-lasting due to their persistence and widespread dispersion. Current regulations, like the International Maritime Organization's (IMO) guidelines, reveal gaps in enforcement and fail to fully address the long-term consequences of spills. Recent technological innovations and policy interventions aim to mitigate risks, but there's an urgent need for coordinated global action, stricter controls, and investment in biodegradable alternatives to safeguard marine environments and ensure ecological sustainability.

Synthetic Degradable Polyvinyl Alcohol Polymer and Its Blends with Starch and Cellulose-A Comprehensive Overview

Approximately 50% of global plastic wastes are produced from plastic packaging, a substantial amount of which is disposed of within a few minutes of its use. Although many plastic types are designed for single use, they are not always disposable. It is now widely acknowledged that the production and disposal of plastics have led to a plethora of negative consequences, including the contamination of both groundwater and soil resources and the deterioration of human health. The undeniable impact of excessive plastic manufacturing and waste generation on the global plastic pollution crisis has been well documented. Therefore, degradable polymers are a crucial solution to the problem of the non-degradation of plastic wastes. The disadvantage of degradable polymers is their high cost, so blending them with natural polymers will reduce the cost of final products and maximize their degradation rate, making degradable polymers competitive with industrial polymers that are currently in use daily. In this work, we will delineate various degradable polymers, including polycaprolactone, starch, and cellulose. Furthermore, we will elucidate several aspects of polyvinyl alcohol (PVA) and its blends with natural polymers to show the effects of adding natural polymers on PVA properties. This paper will study cost-effective and ecologically acceptable polymers by combining inexpensive natural polymers with readily accessible biodegradable polymers such as polyvinyl alcohol (PVA).

Polyethylene terephthalate waste derived nanomaterials (WDNMs) and its utilization in electrochemical devices

Plastics are a vital component of our daily lives in the contemporary globalization period; they are present in all facets of modern life. Because the bulk of synthetic plastics utilized in the market are non-biodegradable by nature, the issues associated with their contamination are unavoidable in an era dominated by polymers. Polyethylene terephthalate (PET), which is extensively used in industries such as automotive, packaging, textile, food, and beverages production represents a major share of these non-biodegradable polymer productions. Given its extensive application across various sectors, PET usage results in a considerable amount of post-consumer waste, majority of which require disposal after a certain period. However, the recycling of polymeric waste materials has emerged as a prominent topic in research, driven by growing environmental consciousness. Numerous studies indicate that products derived from polymeric waste can be converted into a new polymeric resource in diverse sectors, including organic coatings and regenerative medicine. This review aims to consolidate significant scientific literatures on the recycling PET waste for electrochemical device applications. It also highlights the current challenges in scaling up these processes for industrial application.

Presence of microplastics in the groundwater of volcanic islands, El Hierro and La Palma (Canary Islands)

The increasing amount of plastic litter worldwide is a serious problem for the environment and its biodiversity, ecosystems, animal and human welfare and the economy. The degradation of these plastics leads to microplastics (MPs), which have been reported for the first time in groundwater in the Canary archipelago. This research investigates the presence of MPs at nine different points on La Palma and El Hierro, where samples were collected in galleries, wells and springs during the month of December 2022. Six different polymers were found with Fourier transform infrared spectroscopy (FTIR) - polypropylene (PP), polyethylene (PE), cellulose (CEL), polyethylene terephthalate (PET), polystyrene (PS) and polymethyl methacrylate (PMMA). The particle concentrations found ranged from 1 to 23 n/L, with a maximum particle size of 1900 μm, the smallest being 35 μm. PP and PE were the most common polymers found in the analysis, associated with the use of packaging, disposable products, textiles and water pipes, related to poorly maintained sewerage networks where leaks occur, allowing these MPs to escape into the environment and end up in groundwater. The detection of microplastic pollution in groundwater emphasises environmental hazards, including biodiversity disruption and water source contamination. Additionally, it presents potential risks to human health by transferring contaminants into the food chain and through respiratory exposure.

Effect of enrichment conditions of secondary feeding on the synthesis of polyhydroxyalkanoates (PHAs) by activated sludge

Polyhydroxyalkanoates (PHAs) are biodegradable plastics with great performance and development prospects. However, their traditional anaerobic/aerobic enrichment process requires a high concentration of dissolved oxygen (DO), resulting in high energy consumption. In this study, an anaerobic/oxygen-limited with secondary feeding enrichment mode was used to enhance the synthesis of PHAs while reducing energy consumption. The enrichment process of PHAs-synthesizing bacteria lasted up to 100 days, and the experiment was conducted to investigate the change of the PHAs synthesizing ability of the system in this mode by detecting the PHAs content and community distribution of the activated sludge under different stages. Under these conditions, the system enriched two major genera of PHAs-synthesizing bacteria, Thauera (30.21%) and Thiothrix (21.30%). The content of PHAs in the sludge increased from 4.51% to 30.87% and was able to achieve a concomitant increase in poly(3-hydroxyvalerate) (PHV) monomer content. After nitrogen limitation (C/N = 150) treatment, the content of PHAs reached 63.05%. The results showed that the enrichment mode of anaerobic/oxygen-limited with secondary feeding could enrich more PHAs-synthesizing bacteria and significantly increase the synthesis amount of PHAs, which revealed the great potential of this mode in solid waste value-added and reduce the production cost of PHAs and could provide a theoretical basis for the production of PHAs from activated sludge.

Transparent biodegradable composite plastic packaging film from TEMPO-oxidized cellulose nanofibers

In this research, we develop a method to create biodegradable food packaging films. Initially, TEMPO-oxidized cellulose nanofiber (TOCNF) undergoes sonication to produce well-dispersed single-strain nanofibers. These nanofibers are then blended with waterborne polyurethane (WPU) to enhance their extensibility. To further enhance compatibility between these two components, a non-ionic surfactant, Tween 80, is introduced into the TOCNF/WPU mixture to improve the dispersion of the WPU within the blend. The addition of Tween 80 significantly increases the transparency of the resulting film (Transmittance: 89.4 %, Haze: 2.2 %). Furthermore, the incorporation of the surfactant effectively reduces the formation of wrinkles and cracks during the film drying process, preventing adverse impacts on the film's barrier properties. The thin film further undergoes esterification crosslinking with citric acid to remove its hydrophilic groups for better water vapor barrier properties. The resulting bio-based packaging film exhibits remarkable transparency, strong biodegradability, and superior gas-barrier properties (water vapor and oxygen) compared to commonly used food packaging.

Nanoplastics promote the dissemination of antibiotic resistance genes and diversify their bacterial hosts in soil

The wide application of plastics has led to the ubiquitous presence of nanoplastics and microplastics in terrestrial environments. However, few studies have focused on the mechanism underlying the effects of plastic particles on soil microbiomes and resistomes, especially the differences between nanoplastics and microplastics. This study investigated the microbiome and resistome in soil exposed to polystyrene microplastics (mPS) or nanoplastics (nPS) through 16S rRNA and shotgun metagenomic sequencing. Distinct microbial communities were observed between mPS and nPS exposure groups, and nPS exposure significantly changed the bacterial composition even at the lowest amended rate (0.01%, w/w). The abundance of antibiotic resistance genes (ARGs) in nPS exposure (1%) was 0.26 copies per cell, significantly higher than that in control (0.21 copies per cell) and mPS exposure groups (0.21 copies per cell). It was observed that nanoplastics, bacterial community, and mobile genetic elements (MGEs) directly affected the ARG abundance in nPS exposure groups, while in mPS exposure groups, only MGEs directly induced the change of ARGs. Streptomyces was the predominant host for multidrug in the control and mPS exposure, whereas the primary host was changed to Bacillus in nPS exposure. Additionally, exposure to nPS induced several bacterial hosts to exhibit possible multi-antibiotic resistance characteristics. Our results indicated that the effects of plastic particles on the soil microbial community were size-dependent, and nano-sized plastic particles exhibited more substantial impacts. Both microplastics and nanoplastics promoted ARG transfer and diversified their bacterial hosts. These findings bear implications for the regulation of plastic waste and ARGs.

A City-Wide Emissions Inventory of Plastic Pollution

A global agreement on plastic should have quantitative reduction targets for the emissions of plastic pollution and regular measurements to track success. Here, we present a framework for measuring plastic emissions, akin to greenhouse gas emissions, and demonstrate its utility by calculating a baseline measurement for the City of Toronto in Ontario, Canada. We identify relevant sources of plastic pollution in the city, calculate emissions for each source by multiplying activity data by emission factors for each source, and sum the emissions to obtain the total annual emissions of plastic pollution generated. Using Monte Carlo simulations, we estimate that 3,531 to 3,852 tonnes (T) of plastic pollution were emitted from Toronto in 2020. Littering is the largest source overall (3,099 T), and artificial turf is the largest source of microplastic (237 T). Quantifying source emissions can inform the most effective mitigation strategies to achieve reduction targets. We recommend this framework be scaled up and replicated in cities, states, provinces, and countries around the world to inform global reduction targets and measure progress toward reducing plastic pollution.

Rapid marine degradable poly(butylene oxalate) by introducing promotion building blocks

The design and development of high-performance marine-degradable plastics have long been considered a superior strategy to address marine plastic pollution. To achieve a balance between rapid marine degradability and high performance of polyester plastics, this work designed two series of poly(butylene oxalate) (PBOx) copolymers with intrinsic hydrolysis ability using poly(ethylene oxalate) (PEOx) and poly(glycolic acid) (PGA) as promotion building blocks. The synthesis process, crystallization properties, barrier performance, and mechanical properties of copolymers were comparatively investigated. Additionally, the marine degradability of copolymers received specific focus. The theoretical calculation demonstrated that the introduction of promotion blocks reduced the hydrolysis energy barrier of the copolymers. In general, the results revealed the advantages of PBEOx copolymer in satisfying practicality and better regulating marine degradability. The high gas barrier performance, suitable thermal properties, tunable mechanical properties, and rapid marine degradability endow the copolymer as a promising candidate toward sustainable and marine-degradable plastics.

A comparison study on effects of polyglycerols on physical properties of alginate films

The water solubility and brittleness of unplasticized sodium alginate (SA) films hinder their widely application. Glycerol (GLY), the most commonly used plasticizer, is compatible with alginate due to the formation of hydrogen bonding owing to the hydroxyl functional groups. However, GLY is a small water-soluble molecule, and the resulting leaching problem may lead to decline in mechanical properties of SA films. Aimed at better plasticizers for alginate (ALG) films, this work focuses on the effects of polymerization degree of polyglycerol on physical properties of ALG films. The cross-sectional morphology, crystallinity, mechanical and thermal properties, water solubility, water content and barrier property of ALG films plasticized with GLY, triglycerol (TG) and decaglycerol (DG) were characterized and discussed. Results illustrated that owing to the long molecular chains of TG and DG and their strong interactions with ALG matrix, the plasticized films possessed better mechanical properties, higher water content and lower water solubility. Moreover, it was worth mentioning that even after water treatment, the mechanical properties of ALG-TG and ALG-DG films were superior than that plasticized with GLY. The results of this study were believed to provide particular insights into the plasticization mechanism and the improvement in performance of SA films in packaging applications.

Engineered Geobacillus lipolytic enzymes - Attractive polyesterases that degrade polycaprolactones and simultaneously produce esters

Plastic pollution is one of the biggest environmental problems plaguing the modern world. Polyester-based plastics contribute significantly to this ecological safety concern. In this study, lipolytic biocatalysts GD-95RM and GDEst-lip developed based on lipase/esterase produced by Geobacillus sp. 95 strain were applied for the degradation of polycaprolactone films (Mn 45.000 (PCL45000) and Mn 80.000 (PCL80000)). The degradation efficiency was significantly enhanced by the addition of short chain alcohols. Lipase GD-95RM (1 mg) can depolymerize 264.0 mg and 280.7 mg of PCL45000 and PCL80000, films respectively, in a 24 h period at 30 °C, while the fused enzyme GDEst-lip (1 mg) is capable of degrading 145.5 mg PCL45000 and 134.0 mg of PCL80000 films in 24 h. The addition of ethanol (25 %) improves the degradation efficiency ~2.5 fold in the case of GD-95RM. In the case of GDEst-lip, 50 % methanol was found to be the optimal alcohol solution and the degradation efficiency was increased by ~3.25 times. The addition of alcohols not only increased degradation speeds but also allowed for simultaneous synthesis of industrially valuable 6-hydroxyhexonic acid esters. The suggested system is an attractive approach for removing of plastic waste and supports the principles of bioeconomics.

Ecotoxicological effects of co-exposure biodegradable microplastics polylactic acid with cadmium are higher than conventional microplastics polystyrene with cadmium on the earthworm

Microplastics (MPs) are plastic fragments with particle sizes <5 mm, ubiquitously distributed in terrestrial environments. However, the negative effects of MPs, such as joint-pollution with heavy metals on soil fauna remain controversial. This study investigated survival rate, growth, reproduction, avoidance behavior, histology, biochemical assays, comet assay, qPCR, Cd content, and IBR index. We found that six types of traditional MPs (PC, PP, PVC, LDPE, PET and PS, and PLA (a biodegradable microplastics)) had no adverse effects on earthworm growth, survival and reproduction. Moreover, we found that earthworms exhibit an avoidance behavior towards PLA. Both PS and PLA can exacerbated Cd pollution, leading to loose circular muscle layer, DNA damage in coelomocytes, and impaired antioxidant system due to increased reactive oxygen species (ROS). mRNA level of HSP70 increased under joint-pollution of both PS and Cd or PLA and Cd compared to Cd treatment alone. MPs enhanced Cd accumulation in earthworms in Cd-contaminated soil. Notably, the Integrated Biomarkers Response index revealed that the toxicity of joint PLA and Cd was greater than the joint effect of PS and Cd, which might violate the original intention of biodegradable plastics having non-toxic influence on the soil fauna. Our findings provide new insights into the ecotoxicological effects of MPs, the joint ecotoxicological effects of MPs and Cd on earthworms, and the ecological risks of MPs to soil fauna.

Marine plastic pollution detection and identification by using remote sensing-meta analysis

The persistent plastic litter, originating from different sources and transported from rivers to oceans, has posed serious biological, ecological, and chemical effects on the marine ecosystem, and is considered a global issue. In the past decade, many studies have identified, monitored, and tracked marine plastic debris in coastal and open ocean areas using remote sensing technologies. Compared to traditional surveying methods, high-resolution (spatial and temporal) multispectral or hyperspectral remote sensing data have been substantially used to monitor floating marine macro litter (FMML). In this systematic review, we present an overview of remote sensing data and techniques for detecting FMML, as well as their challenges and opportunities. We reviewed the studies based on different sensors and platforms, spatial and spectral resolution, ground sampling data, plastic detection methods, and accuracy obtained in detecting marine litter. In addition, this study elaborates the usefulness of high-resolution remote sensing data in Visible (VIS), Near-infrared (NIR), and Short-Wave InfraRed (SWIR) range, along with spectral signatures of plastic, in-situ samples, and spectral indices for automatic detection of FMML. Moreover, the Thermal Infrared (TIR), Synthetic aperture radar (SAR), and Light Detection and Ranging (LiDAR) data were introduced and these were demonstrated that could be used as a supplement dataset for the identification and quantification of FMML.

Forecasting global plastic production and microplastic emission using advanced optimised discrete grey model

Plastic pollution has become a prominent and pressing environmental concern within the realm of pollution. In recent times, microplastics have entered our ecosystem, especially in freshwater. In the contemporary global landscape, there exists a mounting apprehension surrounding the manifold environmental and public health issues that have emerged as a result of the substantial accumulation of microplastics. The objective of the current study is to employ an enhanced grey prediction model in order to forecast global plastic production and microplastic emissions. This study compared the accuracy level of the four grey prediction models, namely, EGM (1,1, α, θ), DGM (1,1), EGM (1,1), and DGM (1,1, α) models, to evaluate the accuracy levels. As per the estimation of the study, DGM (1,1, α) was found to be more suitable with higher accuracy levels to predict microplastic emission. The EGM (1,1, α, θ) model has slightly better accuracy than the DGM (1,1, α) model in predicting global plastic production. Various accuracy measurement tools (MAPE and RMSE) were used to determine the model's efficiency. There has been a gradual growth in both plastic production and microplastic emission. The current study using the DGM (1,1, α) model predicted that microplastic emission would be 1,084,018 by 2030. The present study aims to provide valuable insights for policymakers in formulating effective strategies to address the complex issues arising from the release of microplastics into the environment and the continuous production of plastic materials.

Interaction of climate change and marine pollution in Southern India: Implications for coastal zone management practices and policies

Climate change and marine litter are inextricably linked, and their interaction manifests differently depending on the specific environmental and biological characteristics, and other human activities taking place. The negative impacts resulting from those synergistic interactions are threatening coastal and marine ecosystems and the many goods and services they provide. This is particularly pervasive in the coastal zone of the Indian subcontinent. India is already experiencing severe climate change impacts, which are projected to worsen in the future. At the same time, the country is gripped by a litter crisis that is overwhelming authorities and communities and hindering the country's sustainable development goals. The coastal environment and communities of the southern states of Kerala and Tamil Nadu are particularly vulnerable to the impacts of climate change. While these state governments and authorities are stepping up efforts to improve the management of their coastal zones, the scale and severity of these issues are mounting. Here we review the combined effects of climate change and marine litter pollution in Southern India, focusing on the Gulf of Mannar Reserve in Tamil Nadu and the Malabar Coast in Kerala. Finally, we discuss effective management options that could help improve resilience and sustainability.

Sustainable circular biorefinery approach for novel building blocks and bioenergy production from algae using microbial fuel cell

The imminent need for transition to a circular biorefinery using microbial fuel cells (MFC), based on the valorization of renewable resources, will ameliorate the carbon footprint induced by industrialization. MFC catalyzed by bioelectrochemical process drew significant attention initially for its exceptional potential for integrated production of biochemicals and bioenergy. Nonetheless, the associated costly bioproduct production and slow microbial kinetics have constrained its commercialization. This review encompasses the potential and development of macroalgal biomass as a substrate in the MFC system for L-lactic acid (L-LA) and bioelectricity generation. Besides, an insight into the state-of-the-art technological advancement in the MFC system is also deliberated in detail. Investigations in recent years have shown that MFC developed with different anolyte enhances power density from several µW/m² up to 8160 mW/m². Further, this review provides a plausible picture of macroalgal-based L-LA and bioelectricity circular biorefinery in the MFC system for future research directions.

Accumulation and exposure classifications of plastics in the different coastal habitats in the western Philippine archipelago

Studies consistently ranked the Philippines as one of the top contributors of plastic wastes leaking into the ocean. However, most of these were based on probabilities and estimates due to lack of comprehensive ground-truth data, resulting also in the limited understanding of the contributing factors and drivers of local pollution. This makes it challenging to develop science-driven and locally-contextualized policies and interventions to mitigate the problem. Here, 56 sites from different coastal habitats in the western Philippine archipelago were surveyed for macroplastics standing stock, representing geographic regions with varying demography and economic activities. Clustering of sites revealed three potential influencing factors to plastic accumulation: population density, wind and oceanic transport, and habitat type. Notably, the amount and types of dominant plastics per geographic region varied significantly. Single-use plastics (food packaging and sachets) were the most abundant in sites adjacent to densely populated and highly urbanized areas (Manila Bay and eastern Palawan), while fishing-related materials dominated in less populated and fishing-dominated communities (western Palawan and Bolinao), suggesting the local industries significantly contributing to the mismanaged plastics in the surveyed sites. Meanwhile, isolated areas such as islands were characterized by the abundance of buoyant materials (drinking bottles and hygiene product containers), emphasizing the role of oceanic transport and strong connectivity in the oceans. Exposure assessment also identified single-use and fishing-related plastics to be of "high exposure (Type 4)" due to their high abundance and high occurrence. These increase their chances of encountering and interacting with organisms and habitats, thus, resulting into more potential harm. This study is the first comprehensive work done in western Philippines, and results will help contextualize local pollution, facilitating more effective management and policymaking.

Marine plastics, circular economy, and artificial intelligence: A comprehensive review of challenges, solutions, and policies

Global plastic production is rapidly increasing, resulting in significant amounts of plastic entering the marine environment. This makes marine litter one of the most critical environmental concerns. Determining the effects of this waste on marine animals, particularly endangered organisms, and the health of the oceans is now one of the top environmental priorities. This article reviews the sources of plastic production, its entry into the oceans and the food chain, the potential threat to aquatic animals and humans, the challenges of plastic waste in the oceans, the existing laws and regulations in this field, and strategies. Using conceptual models, this study looks at a circular economy framework for energy recovery from ocean plastic wastes. It does this by drawing on debates about AI-based systems for smart management. In the last sections of the present research, a novel soft sensor is designed for the prediction of accumulated ocean plastic waste based on social development features and the application of machine learning computations. Plus, the best scenario of ocean plastic waste management with a concentration on both energy consumption and greenhouse gas emissions is discussed using USEPA-WARM modeling. Finally, a circular economy concept and ocean plastic waste management policies are modeled based on the strategies of different countries. We deal with green chemistry and the replacement of plastics derived from fossil sources.

U.S. plastic waste exports: A state-by-state analysis pre- and post-China import ban

This study analyzes the regional implications of China's 2017 import ban on plastic waste by examining U.S. census data. A statistically significant decrease in total U.S. plastic waste exports was found, dropping from about 1.4 million tons to 0.6 million tons in the post-ban period. California remained the top exporter, throughout both pre- and post-ban periods, while South Carolina exhibited the highest per capita exports. Malaysia emerged as the largest importer of U.S. plastic waste, followed by Vietnam, Indonesia, and Thailand. The ban also led to a change in the composition of the exported plastic waste. Ethylene polymers increased from 32.6% of total exports in the pre-ban period to 46.9% in the post-ban period. Other plastics (vinyl chloride polymers, styrene polymers, and for plastics not elsewhere specified or included) decreased from 67.4% of total exports in the pre-ban period to 53.1% in the post-ban period. Moreover, we found that exporting plastic waste has significant environmental and human health impacts. For example, the Global Warming Potential (GWP) decreased from 20 million tons CO2-eq in the scenario where 100% of plastics are exported, or 25 million tons exported from the U.S. since 2002, to -11.1 million tons CO2-eq in the scenario where 100% of plastics are treated domestically. Transportation exacerbates these impacts for exported waste scenarios, increasing to 5.4 million tons CO2-eq when plastics are exported by ship while decreasing to 0.9 million tons CO2-eq for domestic treatment. Although exporting plastic waste is initially cost-effective, our study highlights that investing in domestic waste management can yield significant long-term benefits, considering the environmental and public health impacts. Therefore, it is crucial to prioritize context-specific solutions to address the challenges of the evolving global plastic waste landscape.

Assessing the embodied carbon and energy required for manufacturing sustainable concrete blocks using plastic pollution as a fiber

This study explores the utilization of polyethylene bags and PET bottles as a fiber in the production of lightweight non-autoclaved plastic fiber-reinforced aerated concrete (NAPFRAC), which has the potential to replace conventional bricks. The study begins by examining global plastic pollutant production and their characterization and the need for a forecast of plastic pollution worldwide. Optimization using Design-Expert 9.0 is used to estimate the optimum mix of NAPFRAC. The mechanical properties of the optimum mix are determined, and a scaled-down model of wall panels is cast to study their behavior and vertical and horizontal ultimate load-carrying capacity. The results are compared to those of conventional first-class burnt clay bricks, and it is found that NAPFRAC wall panels show a 28% increase in vertical load-carrying capacity and 40% in horizontal load-carrying capacity. An analytical study of a high-rise building with NAPFRAC as infill panels is carried out to check the reduction of steel reinforcement in structural sections. Microstructural analysis using SEM (scanning electron microscopy) and XRD (X-ray diffraction) is conducted to identify the morphology and mineralogical composition of the NAPFRAC. Energy studies are also carried out on the mix ratio to identify the embodied carbon dioxide and energy required. Overall, this study highlights the potential of NAPFRAC as a lightweight alternative to conventional bricks. The use of plastic waste as a fiber in concrete production could have a positive impact on the environment by reducing plastic pollution. The results of this study could also have practical applications in the construction industry, especially in the design of high-rise buildings.

Cleaning Up without Messing Up: Maximizing the Benefits of Plastic Clean-Up Technologies through New Regulatory Approaches

As the global plastics crisis grows, numerous technologies have been invented and implemented to recover plastic pollution from the environment. Although laudable, unregulated clean-up technologies may be inefficient and have unintended negative consequences on ecosystems, for example, through bycatch or removal of organic matter important for ecosystem functions. Despite these concerns, plastic clean-up technologies can play an important role in reducing litter in the environment. As the United Nations Environment Assembly is moving toward an international, legally binding treaty to address plastic pollution by 2024, the implementation of plastic clean-up technologies should be regulated to secure their net benefits and avoid unintended damages. Regulation can require environmental impact assessments and life cycle analysis to be conducted predeployment on a case-by-case basis to determine their effectiveness and impact and secure environmentally sound management. During operations catch-efficiency and bycatch of nonlitter items, as well as waste management of recovered litter, should be documented. Data collection for monitoring, research, and outreach to mitigate plastic pollution is recommended as added value of implementation of clean-up technologies.

An integrated approach to remove endocrine-disrupting chemicals bisphenol and its analogues from the aqueous environment: a review

Bisphenol A (BPA) is a well-known endocrine-disrupting chemical (EDC) used as a plastic enhancer in producing polycarbonate resins to manufacture hard plastics. Due to strict limitations on the manufacturing and utilization of BPA, several bisphenol substitutes, bisphenol F (BPF), bisphenol S (BPS), and bisphenol AF (BPAF), have been developed to replace it in various applications. Because of their widespread use in food containers, infant bottles, and reusable water bottles, bisphenols (BPs) have been identified in different environmental circumstances, including drinking water, seawater, industrial effluent, and endocrine systems such as human blood, urine, and breast milk. However, locating and analyzing them in different conditions has proven to be challenging. Therefore, there is a need to reduce the prevalence of BPs in the environment. The significance of advanced treatment options for treating and eliminating BPA and its alternatives from water bodies are reviewed. Also, the research gaps and future scopes are discussed in this review article. According to the literature survey, adsorption and photocatalytic degradation provide synergistic benefits for environmental challenges because of their substantial adsorption Q5 capacity, high oxidation capability, and low cost compared to alternative individual treatment options.

Plastic debris in lakes and reservoirs

Plastic debris is thought to be widespread in freshwater ecosystems globally¹. However, a lack of comprehensive and comparable data makes rigorous assessment of its distribution challenging^2,3. Here we present a standardized cross-national survey that assesses the abundance and type of plastic debris (>250 μm) in freshwater ecosystems. We sample surface waters of 38 lakes and reservoirs, distributed across gradients of geographical position and limnological attributes, with the aim to identify factors associated with an increased observation of plastics. We find plastic debris in all studied lakes and reservoirs, suggesting that these ecosystems play a key role in the plastic-pollution cycle. Our results indicate that two types of lakes are particularly vulnerable to plastic contamination: lakes and reservoirs in densely populated and urbanized areas and large lakes and reservoirs with elevated deposition areas, long water-retention times and high levels of anthropogenic influence. Plastic concentrations vary widely among lakes; in the most polluted, concentrations reach or even exceed those reported in the subtropical oceanic gyres, marine areas collecting large amounts of debris⁴. Our findings highlight the importance of including lakes and reservoirs when addressing plastic pollution, in the context of pollution management and for the continued provision of lake ecosystem services.

Biological Degradation of Plastics and Microplastics: A Recent Perspective on Associated Mechanisms and Influencing Factors

Plastic and microplastic pollution has caused a great deal of ecological problems because of its persistence and potential adverse effects on human health. The degradation of plastics through biological processes is of great significance for ecological health, therefore, the feasibility of plastic degradation by microorganisms has attracted a lot of attention. This study comprises a preliminary discussion on the biodegradation mechanism and the advantages and roles of different bacterial enzymes, such as PET hydrolase and PCL-cutinase, in the degradation of different polymers, such as PET and PCL, respectively. With a particular focus on their modes of action and potential enzymatic mechanisms, this review sums up studies on the biological degradation of plastics and microplastics related to mechanisms and influencing factors, along with their enzymes in enhancing the degradation of synthetic plastics in the process. In addition, biodegradation of plastic is also affected by plastic additives and plasticizers. Plasticizers and additives in the composition of plastics can cause harmful impacts. To further improve the degradation efficiency of polymers, various pretreatments to improve the efficiency of biodegradation, which can cause a significant reduction in toxic plastic pollution, were also preliminarily discussed here. The existing research and data show a large number of microorganisms involved in plastic biodegradation, though their specific mechanisms have not been thoroughly explored yet. Therefore, there is a significant potential for employing various bacterial strains for efficient degradation of plastics to improve human health and safety.

One-pot treatment of Saccharophagus degradans for polyhydroxyalkanoate production from brown seaweed

The conventional production of polyhydroxyalkanoate (PHA) from waste biomass requires a pretreatment step (acid or alkali) for reducing sugar extraction, followed by bacterial fermentation. This study aims to find a greener approach for PHA production from brown seaweed. Saccharophagus degradans can be a promising bacterium for simultaneous reducing sugar and PHA production, bypassing the need for a pretreatment step. Cell retention cultures of S. degradans in membrane bioreactor resulted in approximately 4- and 3-fold higher PHA concentrations than batch cultures using glucose and seaweed as carbon sources, respectively. X-ray diffraction, Fourier transform infrared spectroscopy, and nuclear magnetic resonance results revealed identical peaks for the resulting PHA and standard poly(3-hydroxybutyrate). The developed one step process using cell retention culture of S. degradans could be a beneficial process for scalable and sustainable PHA production.

Instant deep sea debris detection for maneuverable underwater machines to build sustainable ocean using deep neural network

Deep sea debris is any persistent man-made material that ends up in the deep sea. The scale and rapidly increasing amount of sea debris are endangering the health of the ocean. So, many marine communities are struggling for the objective of a clean, healthy, resilient, safe, and sustainably harvested ocean. That includes deep sea debris removal with maneuverable underwater machines. Previous studies have demonstrated that deep learning methods can successfully extract features from seabed images or videos, and are capable of identifying and detecting debris to facilitate debris collection. In this paper, the lightweight neural network (termed DSDebrisNet), which can leverage the detection speed and identification performance to achieve instant detection with high accuracy, is proposed to implement compound-scaled deep sea debris detection. In DSDebrisNet, a hybrid loss function considering the illumination and detection problem was also introduced to improve performance. In addition, the DSDebris dataset is constructed by extracting images and video frames from the JAMSTEC dataset and labeled using a graphical image annotation tool. The experiments are implemented on the deep sea debris dataset, and the results indicate that the proposed methodology can achieve promising detection accuracy in real-time. The in-depth study also provides significant evidence for the successful extension branch of artificial intelligence to the deep sea research domain.

Persistence of algal toxicity induced by polystyrene nanoplastics at environmentally relevant concentrations

Polystyrene (PS) often found in the ocean is one of the most commonly used plastic polymers in the world and can exist in different particle sizes. In particular, PS degrades relatively faster and widely accumulates at the nanoscale. Therefore, the penetration is strong and it is easy to enter the body and cause adverse effects. However, the persistence or recovery of their toxicity remains largely unclear. Here, we designed two subexperiments (exposure and recovery experiments) and investigated the persistence of the toxicity of polystyrene (PS) NPs at a wide concentration range (0.01-10 mg/L) to diatoms (Phaeodactylum tricornutum). PS-NPs significantly inhibited algal growth and clearly wrinkled the surfaces of cells, membrane permeability was significantly increased, and the steady-state state of cell redox and mitochondrial membrane potential was disturbed. However, in the recovery experiment, the increased membrane permeability was observed to persist, but the induced oxidative damage was reversible, and the absorbed NPs could be excreted. Integrated omics techniques (metabolomics and transcriptomics) revealed that PS-NPs significantly disrupts cell metabolism, including disturbances in fatty acid biosynthesis and enhanced biosynthesis of phenylalanine, tyrosine, and tryptophan. Inhibition of fatty acid, amino acid, energy and carbohydrate metabolism and disturbance of the antioxidant system contribute to the persistence of toxicity. These findings highlight the phenomena and mechanisms of the persistence of phytotoxicity and are critical to the accurate assessment of NPs.

A multi-criteria assessment of the implementation of innovative technologies to achieve different levels of microplastics and macroplastics reduction

This paper proposes and applies a multicriteria decision analysis framework tailored to assess measures for reducing the concentration of microplastics and macroplastics in seas, by implementing ground-breaking clean-up technologies and addressing different types of pollutant sources. Environmental, socio-economic and financial impacts are considered to provide a ranking of these measures for better-informed decision making. The data required to evaluate the performance of the technologies in different locations and scales are analyzed to understand the consequences of the different measures in terms of plastic pathways and sites, and the amounts accumulated, using innovative simulation models. The framework is applied to the Mediterranean Sea, providing insights for designing measures to respond to the challenges of cleaning seas and fulfill the EU marine strategy. The results for the best ranked alternatives show that dealing with microplastics is much more expensive (by one order of magnitude) than dealing with macroplastics.

Insights into Anthropogenic Micro- and Nanoplastic Accumulation in Drinking Water Sources and Their Potential Effects on Human Health

Anthropogenic microplastics (MPs) and nanoplastics (NPs) are ubiquitous pollutants found in aquatic, food, soil and air environments. Recently, drinking water for human consumption has been considered a significant pathway for ingestion of such plastic pollutants. Most of the analytical methods developed for detection and identification of MPs have been established for particles with sizes > 10 μm, but new analytical approaches are required to identify NPs below 1 μm. This review aims to evaluate the most recent information on the release of MPs and NPs in water sources intended for human consumption, specifically tap water and commercial bottled water. The potential effects on human health of dermal exposure, inhalation, and ingestion of these particles were examined. Emerging technologies used to remove MPs and/or NPs from drinking water sources and their advantages and limitations were also assessed. The main findings showed that the MPs with sizes > 10 μm were completely removed from drinking water treatment plants (DWTPs). The smallest NP identified using pyrolysis-gas chromatography-mass spectrometry (Pyr-GC/MS) had a diameter of 58 nm. Contamination with MPs/NPs can occur during the distribution of tap water to consumers, as well as when opening and closing screw caps of bottled water or when using recycled plastic or glass bottles for drinking water. In conclusion, this comprehensive study emphasizes the importance of a unified approach to detect MPs and NPs in drinking water, as well as raising the awareness of regulators, policymakers and the public about the impact of these pollutants, which pose a human health risk.

Spatio-temporal evaluation and risk assessment of microplastics in nearshore surface waters post-2018 Kerala deluge along the southwest coast of India

Spatial and temporal distribution of microplastics along the nearshore surface waters of Kerala after the floods of 2018 was studied. Results indicated a seven-fold increase in its mean concentration (7.14 ± 3.03 items/m³) post deluge. The average abundance was highest during pre-monsoon (8.27 ± 3.09 items/m³). Fibres were the dominant group, with blue and black being the most prevalent colours. Polyethylene and polypropylene were the most commonly found polymers, possibly gaining entry through sewage waste or land-based plastic litter. Highest abundance of microplastic was recorded off Kochi categorising it at Hazard Level I under Pollution Load Index assessment. Similarly high levels of Pollution Hazard Index and Potential Ecological Risk Index were also reported due to the presence of hazardous polymers PVC and PU that can cause concern to marine life. The differential weathering pattern and surface morphology analysis suggested microplastics to be relatively old that had undergone substantial mechanical and oxidative weathering.

Preparation of Waste PP/Fly Ash/Waste Stone Powder Composites and Evaluation of Their Mechanical Properties

The research was carried out to analyze the combined and mechanical properties of polypropylene (PP)/fly ash (FA)/waste stone powder (WSP) composite materials. PP, FA and WSP were mixed and prepared into PP100 (pure PP), PP90 (90 wt% PP + 5 wt% FA + 5 wt% WSP), PP80 (80 wt% PP + 10 wt% FA + 10 wt% WSP), PP70 (70 wt% PP + 15 wt% FA + 15 wt% WSP), PP60 (60 wt% PP + 20 wt% FA + 20 wt% WSP) and PP50 (50 wt% PP + 25 wt% FA + 25 wt% WSP) composite materials using an injection molding machine. The research results indicate that all PP/FA/WSP composite materials can be prepared through the injection molding process and there are no cracks or fractures found on the surface of the composite materials. The research results of thermogravimetric analysis are consistent with expectations, indicating that the preparation method of the composite materials in this study is reliable. Although the addition of FA and WSP powder cannot increase the tensile strength, it is very helpful to improve the bending strength and notched impact energy. Especially for notched impact energy, the addition of FA and WSP results in an increase in the notched impact energy of all PP/FA/WSP composite materials by 14.58-22.22%. This study provides a new direction for the reuse of various waste resources. Moreover, based on the excellent bending strength and notched impact energy, the PP/FA/WSP composite materials have great application potential in the composite plastic industry, artificial stone, floor tiles and other industries in the future.

Investigating on the toxicity and bio-magnification potential of synthetic glitters on Artemia salina

Our research aims to assess the toxic impacts of polyethylene terephthalate (PET) glitters on Artemia salina as a model zooplankton. The mortality rate was assessed using a Kaplan Maier plot as a function of various microplastic dosages. The ingestion of microplastics was confirmed by their presence in digestive tract and faecal matter. Gut wall damage was confirmed by dissolution of basal lamina walls and an increase in the secretory cells. A significant decrease in the activities of cholinesterase (ChE) and glutathione-S-transferase (GST) were noted. A decrease in catalase activity could be correlated to an increase in the generation of reactive oxygen species (ROS). Cysts incubated in presence of microplastics exhibited delay in their hatching into 'umbrella' and 'instar' stages. The data presented in the study would be useful for scientists working on discovering new sources of microplastics, related scientific evidences, image data and model of study.

The challenge of reducing macroplastic pollution: Testing the effectiveness of a river boom under real environmental conditions

Improving collection technologies is crucial to develop effective and economically feasible solutions for catching plastic from riverine environments. However, floating booms are being constructed and deployed in river around the world without rigorously testing its effectiveness. In this study, we tested the effectiveness of a boom under realistic conditions for several configurations and treatments (including "C-shape" and "Slash-shape" configurations). For this, we used the same macroplastics that leak out of waste management channels in order to be as realistic as possible. In total we used 52 plastic articles of 13 different polymers. The global effectiveness of the tested C-shape boom was lower than expected under such conditions (around 37 % of retention). The effectiveness of the Slash-shape boom was considerably worst (<10 %). However, the effectiveness varies greatly according to the particular characteristics of the plastic articles (i.e., shape and polymer composition), ranged from 0 to 100 %. For example, the boom could be 100 % effective retaining plastics such as Stylofoam trays and cups, 40-20 % for food-wrappers but 0 % for disposable plates and spoons, straws, monofilament fishing lines, packaging straps, hoses, pipes, elastic bands, etc. It seems that to have a reasonable catch-effectiveness and be cost-efficient, boom designs need to be improved and tested under different environmental conditions before to reach the market. In addition, it is unrealistic to select only high buoyancy plastics for testing them.

Microplastic Presence in the Digestive Tract of Pearly Razorfish Xyrichtys novacula Causes Oxidative Stress in Liver Tissue

Plastic pollution in the oceans is a growing problem, with negative effects on exposed species and ecosystems. Xyrichtys novacula L. is a very important fish species both culturally and economically in the Balearic Islands. The aim of the present study was to detect and categorise the presence of microplastics (MPs) in the digestive tract of X. novacula, as well as the existence of oxidative stress in the liver. For this purpose, the fish were categorised into two groups based on the number of MPs observed in the digestive tracts: a group with no or low presence of MPs (0-3 items) and a group with a higher presence of MPs (4-28 items). MPs were found in 89% of the specimens analysed, with a dominance of fibre type and blue colour. Regarding the type of polymer, polycarbonate was the most abundant, followed by polypropylene and polyethylene. For the group with a greater presence of MPs, the activities of the antioxidant enzymes glutathione peroxidase and glutathione reductase, as well as the phase II detoxification enzyme glutathione s-transferase, were higher than the activities observed in fish with little to no presence of MPs. The activities of catalase and superoxide dismutase and the levels of malondialdehyde did not show significant differences between both groups. In conclusion, these results demonstrate the presence of MPs in the digestive tract of X. novacula and the existence of an antioxidant and detoxification response, mainly based on the glutathione-based enzymes.

How microplastics interact with food chain: a short overview of fate and impacts

Microplastics as one of the ubiquitous contaminants have recently attracted attentions. Microplastics have the potential to impact the social-ecological environment. Accordingly, negating adverse effects on the environment necessitates scrutinizing physical and chemical characteristics of microplastics, emission sources, effects on the ecological environment, contaminated food chains especially human food web, and the impacts on human health. Microplastics are defined as very small plastic particles with a size smaller than 5 mm, which come in heterogeneous colors depending on their emission source and are composed of thermoplastics and thermosets. These particles based on their emission source are classified into primary and secondary microplastics. These particles diminish the quality of terrestrial, aquatic and air environments, which directly impact the habitats and trigger disruptions in plants and wild life. The adverse effects of these particles are multiplied when adsorbing to toxic chemicals. Moreover, these particles have the potential to be transmitted in organisms and human food chain. Due to the fact that the retention time in the body of organisms is longer than the time elapsed from ingestion to excretion, microplastic bioaccumulation occurs in the food webs.

A comprehensive assessment of plastic remediation technologies

The global presence of plastic litter and its accumulation in the environment has become an issue of concern to the public and policymakers. This concern has triggered innovators in past decades to design and develop a multitude of remediation technologies to prevent plastic from entering the environment, or to clean up legacy litter. This study aims to (i) systematically review the current scientific literature on plastic remediation technologies, (ii) create a 'plastic clean-up and prevention overview' illustrating 124 remediation technologies and 29 characteristics, (iii) qualitatively analyse their key characteristics (e.g., fields of application, targeted plastic), and (iv) investigate challenges and opportunities of clean-up technologies for inland waterways (e.g., canals, rivers) and ports. We identified 61 scientific publications on plastic remediation technologies, until June 2022. Thirty-four of these studies were published within the last three years, demonstrating a growing interest. The presented overview indicates that inland waterways are, so far, the preferred field of application, with 22 technologies specifically designed for cleaning up plastics from inland waterways, and 52 additional ones with the potential to be installed in these locations. Given the importance of clean-up technologies in inland waterways, we highlighted their strengths, weaknesses, opportunities, and threats (SWOT). Our results indicate that, despite the challenges, these technologies provide essential prospects, from improving the environmental quality to raising awareness. Our study is instrumental as it illustrates an up-to-date overview and provides a comprehensive analysis of current in design phase, testing, and in use plastic remediation technologies.

Investigating the evolution of the technologies for collecting microplastics

To stop the dispersion of microplastics in the ecosystem, many technologies for collecting them were designed, tested and developed in the last period. However, a complete and exhaustive comparison of these technologies to guide in the choice and/or in the development of the most suitable appropriate one is missing in the literature. This study investigates the presence of some known technological trends, deriving from the TRIZ (Russian acronym for "Theory of Inventive Problem Solving") in the behaviour (i.e. the operating principle) of these technologies. To do this, a systematic methodology was followed, which has a general value and consists in analysing the patents relating to these technologies through various bibliometric indexes (i.e. Innovation index, Emergence Score index, Independent Claims index and Technology Cycle Time index). In general, the obtained results did not reveal a clearly identifiable ranking of the behaviour which was unanimously confirmed by all the considered bibliometric indexes. In addition, the average of the scores of the different indexes associated with the different behaviours equalized their differences. However, these results are mainly due to the markedly different evaluations obtained by the Emergence Score index compared to those of the other indexes. From the comparison of the results with the evolutionary trends, it emerged that the operative zone reduction trend was the most confirmed, while the technical system dematerialization was the least confirmed by the bibliometric analysis of all the indexes. In particular, the ranking of the behaviours provided by the Innovation index best confirmed all the evolutionary trends, while that of the Emergence Score index was the worst. In conclusion, this study confirmed the adherence of the development that technologies for collecting microplastics are following to the evolutionary trends through bibliometric analysis: this sequence places magnetic technologies in first place, followed by chemical, fluid dynamics, dynamic mechanics and static mechanics. The analysis of the performances declared in the patents substantially confirms this result.