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Plastic pollution in river environments has become an emerging global concern. However, the migration of plastic and changes in its properties between river compartments are less understood. This study demonstrates the plastic debris aging and the dynamics between floodplain, surface water, and sediment compartments of the Tuul River, Mongolia. Plastic occurrence is evaluated in terms of their abundance, size, shape, polymer type, and photodegradation in each compartment. Photodegradation stages were calculated using the carbonyl index (CI). Plastic abundance was 5.46 ± 3.53 items m−2 in the floodplain, 155 ± 100.7 items m−3 in the surface water, and 128.4 ± 76.3 items kg−1 in the sediment. Microplastics dominated in the size category in all compartments, while macro- and megaplastics were found only in the floodplain. Polyethylene and polypropylene dominated the surface water and sediment, while polystyrene was the predominant plastic in the floodplain. A positive correlation was found between the distributed polymer types in the surface water and sediment compartments. The similar composition in size and polymer type suggests vertical plastic migration from water to sediment. Although CI values showed that the plastic aging was significantly different between water and sediment (water, 0.61 ± 0.26, and sediment, 0.90 ± 0.68), the dominance of low-density plastics with high CI in the sediment suggests that the aged plastic density changed during the vertical transport in the river system. [ABSTRACT FROM AUTHOR]

Macroplastics are a global threat to the aquatic environment and will degrade into microplastics over time. Its presence in canal causes pollution and inhibits water flow, causing flooding in urban areas; therefore, it is essential to identify and monitor its presence. Addressing knowledge gaps is critical in determining solutions for mitigation purposes. In visual object detection studies, aerial mapping is developed with advanced technology, such as unmanned aerial vehicles (UAV). This research aims to conduct aerial mapping experiments to find the right formula or technical reference for detecting macroplastic waste objects floating on the surface of the canal, including flight altitude, exposure to sunlight, and the influence of season on object detection. Aerial mapping will be done in densely populated urban canals in Southeast Asia, Indonesia, and Makassar City. The aerial mapping survey method will be used, and then the data will be processed in the digitization process and object detection with GIS. The analysis kernel in GIS tools will be used to see the distribution density of macroplastics. The research results show that autoblock occurs at heights of 5m and 10m, but this autoblock can be minimized at a flight height of 15 m. Apart from that, height also affects flight duration. The lower flying height will result in better visual accuracy and better resolution. However, at a height of 15m, macroplastic objects were still detected on a moderate scale. This research successfully distinguished various plastic waste materials, the most found being the soft polyolefin category in plastic bags. Monitoring results detected 321 items of macroplastics in the dry season and 1,163 in the rainy season, or a threefold increase with conditions spread thinly in the dry season. In the rainy season, they gather densely on one side of the canal. [ABSTRACT FROM AUTHOR]

Background: This review reveals the role of linear economy prevalence and mismanagement practices in plastic pollution of aquatic and terrestrial environments and related knowledge gaps in Romania while outlining downstream and upstream solutions to reduce plastic pollution and adopt circular economy strategies. Thus, the major aim of this study is the investigation of the stage of scientific knowledge concerning all these demands in the Romanian context. Methodology: This work integrates two main approaches: (i) a bibliometric analysis fed by Web of Science and Scopus databases to reveal the current coverage of peer-reviewed literature related to plastic waste in Romania and (ii) a subject-based review to underline the main themes related to plastic waste management, plastic pollution, and mitigating options in Romania in line with circular economy principles. Results: Reducing plastic pollution requires scientific knowledge, multi-sectoral cooperation, and societal awareness. Following this, the topics of plastic waste and plastic pollution appeared to be under-investigated in the literature considering Romania as a case study and concentrated around the 2020 year, emphasizing, in this way, the trendiness of plastic waste concerns and their management in the current research landscape. Our analysis points out that: (i) Romania is facing massive plastic pollution requiring solid improvements in waste management performances; (ii) few peer-reviewed research studies are performed in Romania for both macro and microplastic concerns with unknown pollution levels in most of its geographical regions; (iii) the plastic waste management is still understudied here, while waste statistics are poorly available at local levels; (iv) the perspectives of circular economy transition are still limited, feeding the plastic pollution in the coming years. Conclusions: Several knowledge gaps are identified and must be covered by future research such as (i) adjusting mismanaged plastic waste levels to regional waste management performances and determining littering rates in urban and rural areas to improve the plastic pollution modeling inputs; (ii) examining plastic pollution associated with landfill sites and waste imports; (iii) assessing the sectoral contributions to macro and microplastic pollution of aquatic environments related to municipalities, tourist destinations, agriculture, etc.; (iv) determining retention levels of plastic in river basins and role of riparian vegetation; (v) analyzing microplastics presence in all types of freshwater environments and interlinkage between macroplastic fragmentation and microplastic; (vi) assessing the plastic loads of transboundary rivers related to mismanagement practices; (vii) determining concentrations of microplastics in air, soil, and other land use ecosystems. [ABSTRACT FROM AUTHOR]

Plastic pollution in the hydrosphere ranks among the most pervasive environmental issues since the inception of the plastic industry and its widespread use in our daily lives. Nowadays, numerous countries worldwide suffer from this pollution not only along coastlines but also in deep-sea ecosystems. Our study carried out in the Gulf of Annaba aims to assess the prevalence and spatial distribution of plastic waste. Sampling was conducted at four coastal sites: El Battah, Seybousse, Rizzi Amor, and Ain Achir, both before and after the Covid-19 pandemic. The results reveal varying rates of macro and microplastic contamination, influenced by geographical differences, urban activities, and hydrodynamic factors. Moreover, the proportions of contamination depend on the types of waste. Furthermore, our study showed a clear divergence, particularly in two periods before and after the pandemic. Due to the lockdown, implemented in 2020, there was a marked decrease in the percentage of sediment plastic pollution, attributed to reduced human activity and partial cessation of industrial operations in these areas. [ABSTRACT FROM AUTHOR]

Background: Plastic greenhouse farming has become widespread worldwide because of its contributions to various agricultural production. However, it also generates plastic waste in large quantities and pollutes farmlands. Contrary to studies on microplastics, few studies have quantified macroplastic contamination in agricultural farmlands despite its contribution to the production of microplastics through fragmentation. Thus, there is a paucity of knowledge on the levels and characteristics of macroplastics in greenhouse environments. Thus, this study aimed to quantify and examine the macroplastic litter on soil surfaces under fallow greenhouse farmlands. Results: The study was conducted at three sites in Southern Hungary, where the usage of plastic greenhouses is very common for cultivating vegetables. On the studied fallow plots, the overall mean abundance of macroplastics was 431 pieces/ha or 6 kg/ha. Most of the fragments had 0.5- to 5-cm sizes. The macroplastic fragmentation in the area was well detected and was an ongoing process. The dominant plastic types were polyethylene and polyvinyl chloride in the form of films and fragments. The results showed that agricultural litter comprised 90% of the total contamination, whereas nonagricultural litter (10%) due to illegal littering also appeared on the plots. Conclusions: Given that macroplastics were found in the studied greenhouse farmlands, we recommend the following: (1) careful cleaning and disposal of plastics on greenhouse farmlands and (2) prevention of greenhouse farmland contamination by external and nonagricultural contaminants. Besides, further research is needed to elucidate the duration of macroplastic fragmentation to microplastic contaminants in greenhouse environments. [ABSTRACT FROM AUTHOR]

Plastics have brought many benefits to society, but their mismanagement has turned them into a serious environmental problem. Today, the effects of plastic waste on wildlife are becoming increasingly evident. Since studies on plastic pollution have focused on species in marine ecosystems, here we review current knowledge on interactions between terrestrial mammals and plastic waste in the countries of the Americas, which is a global hotspot of mammalian biodiversity and in turn has, among its member countries, nations with high per capita generations of plastic waste globally. We identified 46 scientific articles documenting plastic ingestion in 37 species and four species that used plastic waste for nest or burrow construction. Of the 46 investigations, seven focused on plastic contamination, while the others reported on the presence of plastics in wildlife, even though this was not the primary focus of the research. However, these publications lack analytical methods commonly used in plastic studies, and only one study applied a standardized methodology for plastic detection. Therefore, in general, plastic pollution research on terrestrial mammals is limited. We extend several recommendations such as designing methodologies that are adapted to terrestrial mammals for the identification of plastics in fecal matter or gastrointestinal contents, carrying out species-specific analyzes on the impacts of plastics in nests or burrows, and giving further attention to this understudied issue and taxa. [ABSTRACT FROM AUTHOR]

The climbing perch Anabas testudineus is widespread in the inland waters of Vietnam and according to its ecology could have contact with floating plastic waste. Fragments of expanded polystyrene (EPS) are detected in the fresh waters of Vietnam in Khanh Hoa, Lam Dong, and Phu Yen provinces. Our study focused on estimating the probability of ingestion of EPS pellets (size 2.5–3.5 mm) by adult climbing perch. In the experiments, 3 types of treatment pellets were offered to fish: 24 feed pellets (Fps), 24 expanded polystyrene pellets (Pps), and 12 feed and 12 expanded polystyrene pellets (FPps). Fish grasping time of the first pellet was independent in all treatment types. The grasping time of the 12th pellet was insignificant in Fps (63 s) and Pps (75 s). Climbing perch grasped and ingested the 24th Fp significantly (p = 0.02) earlier (143 s), than they grasped the 24th Pp (817 s). Fish with FPp treatment grasped feed along with EPS pellets, but grasping the 12th Fp was significantly (p = 0.02) earlier (49 s) than the 12th Pp (193 s). By the end of the tests, the fish had ingested all feed pellets. We discovered that climbing perch grasped Pps and kept them in the oral cavity, but rejected them in 100% of the cases. This result provided evidence that climbing perch have an effective defense mechanism for avoiding ingestion of expanded polystyrene pellets with a size of 2.5–3.5 mm. [ABSTRACT FROM AUTHOR]

The research on the impact of plastic pollution on biodiversity has primarily focused on aquatic ecosystems, especially marine ones. Therefore, it is vital to assess how plastic pollution affects other environments and organisms, including terrestrial invertebrates. These organisms are widely recognized for their susceptibility to environmental changes and pollution. The objectives of this study were i) to investigate the potential influence (positive or negative) of macroplastic debris (MaP) on invertebrates inhabiting riverine sandy environments, ii) the potential occurrence of the microplastic (MP) adherence phenomenon on the invertebrate's body by entanglement on the body's setae or electrostatic effect (i.e., bioadhesion), and iii) the effects of removal of debris on the colonized diversity. By performing a mesocosm experiment, emulating a "small-scale dump" (also called micro-waste sites), we found that terrestrial invertebrates show a preference for colonizing areas rich in MaP, resulting in higher species richness in these areas (39 taxa in areas containing plastic debris vs. 21 taxa in areas free of plastics). This preference is likely due to the provision of shade, protection, and distinct micro-habitats offered by MaP. Regarding MP, we observed a significant number of invertebrates with MPs attached to their bodies (4.3 ± 0.8 MPs attached per individual), mainly wolf spiders (Lycosidae) and ground beetles (Carabidae), suggesting potential negative ecological implications that are discussed herein. [Display omitted] • Terrestrial invertebrates showed greater diversity in areas affected by plastics. • Small-scale dumps can serve as refuges and feeding grounds for invertebrates. • Invertebrates exhibited bioadhesion of microplastics on their bodies. [ABSTRACT FROM AUTHOR]

The presence of plastic debris along shorelines is a widespread problem, and plastic debris can interact directly with marine wildlife. In northeast Brazil, the Antillean manatees are the most common marine mammals and use estuarine waters mainly as their home range. We aimed to investigate the characteristics of plastic debris on the estuarine-oceanic continuum and the accumulation density of plastic on beaches. The density of plastic debris on beaches located in transitional areas was 7–10-fold greater than that on beaches in estuarine and oceanic areas. Fragments were considered the most abundant form of plastic debris on all the beaches. Our findings could lead to improved pollution management in this marine protected area, principally due to the risks of remobilizing small plastic particles through tides and wind effects that scatter them in resting and feeding manatees areas. • Fragments were the most abundant form of plastic debris in the beaches. • The most common color of the plastics was white. • Macro- and mesoplastics were found widely present on all the beaches. • Sand spits provided a barrier to the transport of plastic debris. [ABSTRACT FROM AUTHOR]

Plastic waste has become a hot topic in sustainability and conservation, helped in part by popular documentaries which have highlighted the issue to the general public. Much of the current literature focuses on the effect of microplastics in the marine environment, with very little information on macroplastic interactions or the terrestrial environment. In this report, the management of digit constriction due to macroplastic debris in a Verreaux's eagle owl (Bubo lacteus) is presented, and the role of zoos in decreasing littering behaviour both within the collection and in the wider global context is discussed. [ABSTRACT FROM AUTHOR]

Literature review identified seven principal pathways of plastic debris entry into river systems: waste water treatment plants; combined sewer overflows; on-site wastewater treatment systems; road and rail transport systems; agriculture; industrial sources; and diffuse litter. A further category of 'microplastics' reflects their multiple potential sources, including microplastic breakdown within rivers. Regulatory and management bodies necessarily make operational decisions based on resource limitations and significant uncertainty due to sparse or missing data, requiring a substantial degree of inference. To support this need, we develop a rapid, desk-based approach based on risk criteria to 'fingerprint' likely pathways of plastic pollution based on catchment characteristics. Characteristics of the River Wye system in the UK are reviewed identifying a risk-based 'fingerprint' of potential pathways of plastic entry or accumulation of plastic debris, represented graphically as a colour-coded 'traffic lights' classification. This 'fingerprinting' approach is based on desk-based inference from published materials as a rapid and resource-efficient alternative to intensive data collection, supporting prioritization of further investigation or response measures. We recommend replication of this 'fingerprinting' approach in other river catchments to support operational management of plastic pollution. Where feasible, it may also be down-scaled where sub-catchment or major river reach properties differ significantly. HIGHLIGHTS Unique catchment characteristics influence likely sources of plastics in rivers Seven potential plastic sources were identified, with a residual microplastics category Literature, interviews and surveys can rapidly 'fingerprint' likely plastic sources Fingerprinting can prioritize management and investigations in specific catchments [ABSTRACT FROM AUTHOR]

This study aims to present the identification, abundance, and chemical characterization of plastics in the intertidal zone sediment of two selected beaches in Kota Kinabalu city, Sabah, Malaysia. Plastic debris was classified according to weight and size and was identified for its heavy metal concentrations and polymer types. Results showed that a higher abundance, by more than 2-fold, of plastic debris was found in Kebagu beach (28.7 g) compared to ODEC, UMS (13.4 g). FTIR analysis showed that polypropylene (PP) and polyethylene (PE) were the dominant plastic polymers on both beaches, followed by polystyrene (PS) and polyethylene terephthalate (PET). Five heavy metals (arsenic, chromium, copper, zinc, and nickel) were detected from four types of plastics. The results showed that the concentration of Zn was higher in all four types of plastics on both beaches, with a range of 41 mg/kg–135.3 mg/kg, followed by Cr and As, while Ni was the lowest concentration detected in PE on both beaches: 5.6 mg/kg (ODEC) and 5.1 mg/kg (Kebagu stations). This study confirmed the presence of macro-, meso- and microplastics in both stations. Further studies remain necessary for a better understanding of the sources and fates of the pollutant in the marine environment. Findings from the studies of the Kota Kinabalu beaches have provided baseline data and a clearer understanding of the distribution of plastic debris. This demonstrates that commitments and actions are required to mitigate the potential risk to the ecological system and human health. [ABSTRACT FROM AUTHOR]

Impacts generated by plastic pollution constitute one of the most significant challenges that humanity must face in the next century, receiving increasing attention from the society at large. Thus, quantifying the state of knowledge concerning organisms affected by plastic debris is extremely important to understand threats to marine species. In this context, this study aimed to review and quantify published data on which marine fish species have been reported as interacting with plastic waste through a scientometric analysis carried out on the Web of Science, Scopus and Scielo databases, using a combination of keywords and Boolean operators. Despite no results for Agnatha, Holocephali and Sarcopterygii, this survey registered 116 documents reporting high intake and low entanglement interactions for 310 teleost species and 33 Elasmobranchs. The results indicate increased knowledge production after 2012, reporting a diversity of debris colors, shapes and materials distributed throughout the globe, but with greater research efforts performed in the Northeast Atlantic and the Mediterranean and Black Seas. This study provides analyses, perspectives and suggestions for future assessments, gathering information and seeking to better understand the issue concerning these debris, which represent another threat to the fauna of the world's oceans. [ABSTRACT FROM AUTHOR]

The growing and pervasive presence of plastic pollution has attracted considerable interest in recent years, especially small (< 5 mm) plastic particles known as 'microplastics' (MPs). Their widespread presence may pose a threat to marine organisms globally. Most of the nano and microplastic (N&MP) pollution in marine environments is assumed to originate from land-based sources, but their sources, transport routes, and transformations are uncertain. Information on freshwater and terrestrial systems is lacking, and data on nanoplastic pollution are particularly sparse. The shortage of systematic studies of freshwater and terrestrial systems is a critical research gap because estimates of plastic release into these systems are much higher than those for oceans. As most plastic pollution originates in urban environments, studies of urban watersheds, particularly those with high population densities and industrial activities, are especially relevant with respect to source apportionment. Released plastic debris is transported in water, soil, and air. It can be exchanged between environmental compartments, adsorb toxic compounds, and ultimately be carried long distances, with potential to cause both physical and chemical harm to a multitude of species. Measurement challenges and a lack of standardized methods has slowed progress in determining the environmental prevalence and impacts of N&MPs. An overall aim of this review is to report the sources and abundances of N&MPs in urban watersheds. We focus on urban watersheds, and summarize monitoring methods and their limitations, knowing that identifying N&MPs and their urban/industrial sources is necessary to reduce their presence in all environments. [ABSTRACT FROM AUTHOR]

Plastic pollution is ubiquitous in aquatic environments worldwide. Rivers connect terrestrial and marine ecosystems, playing a key role in the transport of land-based plastic waste towards the sea. Emerging research suggests that in estuaries and tidal rivers, tidal dynamics play a significant role in plastic transport and retention dynamics. To date, observations in these systems have been limited, and plastic transport dynamics during single tidal cycles remain poorly understood. Here, we investigated plastic transport, trapping, and re-mobilization of macroplastics (> 0.5 cm) in the Saigon River, focusing on short-term dynamics of individual tidal cycles. We used GPS trackers, released at different stages of the tidal cycle (ebb, flood, neap, spring). Plastic items demonstrated dynamic and intermittent transport behavior. Items spent almost half of the time (49%) temporarily stopped, mainly due to their entrapment in vegetation, infrastructure, or deposition on riverbanks. Items were almost always re-mobilized within 10 h (85%), leading to successive phases of stopping and transport. Tidal dynamics also resulted in bidirectional transport of plastic items, with median daily total transport distance within the 40 km study reach (8.9 km day−1) over four times larger than the median daily net distance (2.0 km day−1). The median retention time of plastic items within the reach was 21 days (mean = 202 days). In total, 81% of the retrieved items were trapped within water hyacinths, emphasizing the important role of floating vegetation on river plastic transport dynamics. With this paper, we aim to provide data-driven insights into macroplastic transport and retention dynamics in a tropical tidal river. These are crucial in the design of effective intervention and monitoring strategies, and estimating net plastic emission from rivers into the sea. [Display omitted] • Tracked floating macro-plastic items in the Saigon River spent nearly half of their time in the system stopped. • Trajectories show a succession of transport, stopping, and re-mobilization phases. • Tidal dynamics lead to bidirectional transport and large differences between total and net transport velocities. • 80% of the retrieved items were entrapped by in-stream floating vegetation. • Impact of hydrological variability and plastic properties should be further explored. [ABSTRACT FROM AUTHOR]

The analysis of microplastics (MP) is time-consuming which limits our capacity to monitor and mitigate plastic pollution. Here, near infrared (1000–2500 nm) hyperspectral imaging (NIR-HSI) offers an advantage over other spectroscopic techniques because it can rapidly image large areas relative to other systems. While NIR-HSI can successfully detect MP, accuracy and limitations of the method have not been fully explored. In addition, lack of open databases and analysis pipelines increases the barrier to use. In this work, we developed a spectral database containing preproduction pellets, consumer products and marine plastic debris, imaged using a Hyspex SWIR-320me imager. A SIMCA model identified four polymer types: polypropylene, polyethylene, polyethylene terephthalate and polystyrene (PP, PE, PET, PS) to identify MP in hyperspectral images. We determined the accuracy of size estimates for PS MP > 1000 μm using fluorescence microscopy and tested the impact of photooxidation on detection of plastics by NIR-HSI (PE, PP, PS, PET) and subsequent prediction by the SIMCA model. The model performed well across all polymers as shown by high specificity, sensitivity, and accuracy for internal cross validation (>88%), and sensitivity >80% for external validation. PS MP < 500 μm Feret diameter were not consistently detected by NIR-HSI when compared with fluorescence microscopy. However, estimates for Feret diameter were consistent for PS MP > 1000 μm. Analysis by NIR-HSI showed no spectral changes and SIMCA showed no decreased precision with increased photooxidation across polymer types. Recall varied across polymer type and photooxidation stage with no clear trends. This study shows that NIR-HSI is a rapid method which can accurately identify MP of the four most relevant polymer types, precluding the need to analyze particles one at a time. NIR-HSI can be a key technology for environmental monitoring of plastic debris where rapid analysis of multiple samples is required. [Display omitted] • Open spectral database and chemometric model for routine analysis of microplastics. • High performance in identifying microplastics made of four polymer types. • Hyperspectral imaging accurately characterized size of polystyrene microplastics >1000 μm. • Photooxidation did not affect precision of polymer identification. • Promising technique to increase analysis throughput for microplastic monitoring. [ABSTRACT FROM AUTHOR]

Despite the global implementation of plastic waste reduction policies and bans on single use plastics (SuPs), their effectiveness for protecting marine ecosystems remains unclear. Frequent monitoring could confirm policy effectiveness, but this is difficult due to resourcing and logistic constraints. This study tested a 'beach litter' beachcombing citizen science approach that could overcome some constraints. Between November 2018 and January 2021, 168 beach visits led to the collection of 12,659 pieces of litter from a beach in Western Australia. Litter was predominantly plastic (87%) and mostly associated with fishing/boating (34%). Significant reductions in six types of litter, including fishing/boating items, balloons, and straws were detected and four coincided with local government waste mitigation measures. We show potential to harness conscientious beachcombers as citizen scientists to help evaluate plastic policy impact. Furthermore, we propose how to harness this effort and increase spatial and temporal coverage of marine plastic pollution monitoring. [Display omitted] • Beachcombing for litter reveals plastic reduction trends in two-years. • Fisheries related litter, while the highest contributor, had the greatest reduction. • High collection frequency is important in monitoring beach litter concentrations. • On-site 'bins' could capture frequently collected litter for standardised analysis. • Detecting trends in plastic litter volumes is key to evaluate mitigation measures. [ABSTRACT FROM AUTHOR]

For the first time, a quantitative assessment of this pollutant was made at the bottom of the rivers of the Mekong basin, and the features of its accumulation and dynamics in bottom sediments and relationship with abundance of fish and decapods were investigated. Sampling of materials for the research was carried out by bottom trawls in the Mekong delta in Vietnam. The amount of macroplastic caught by the trawl from the bottom averaged 33.4 g/100 m2. The maximum values of the waste content (up to 923.2 g/100 m2) were confined to the districts of large cities. The distribution of macroplastic was characterized by high spatio-temporal variability. Its amount was significantly (p < 0.05) higher in branches with low monthly flow, in shallow-water areas, as well as in the low-water period. During the flood period, which usually lasts from July to November, the amount of macroplastic at the bottom decreased by an average of 2.5 times. In this study a significant relationship between the number of animals and the mass of macroplastics was statistically proven for most species of fish and decapods. The substrate, containing a significant amount of plastic fragments, attracted aquatic organisms. All in all, we present results for poorly understood processes of transport, deposition and influence of plastic debris in large rivers in regions of monsoon subequatorial climate and show that more efforts should be dedicated to further unravel potentially complex pathways of the plastic exposure to water ecosystems. [Display omitted] • Macroplastic is retained in significant quantities in bottom sediments of the Mekong. • Deposition of macroplastic occurs more intensively during the low-water period. • The construction of dams is conducive to the deposition of plastic at the bottom. • Macroplastic attracts fish and decapods, which changes their behavior. [ABSTRACT FROM AUTHOR]

[Display omitted] • Linking observed entanglement prevalence to plastic debris exposure in SSD-approach. • Quantifying a spatially-explicit indicator of potential entanglement impacts. • Presenting application options for life cycle and risk assessments. Marine animals have been known to interact with and become entangled in plastic debris for decades. Despite increasing annual input volumes of plastic waste to the natural environment and the threat this constitutes to marine biodiversity, impacts of mismanaged plastic waste generally remain unquantified in environmental impact assessments. In this paper, we develop a Species Sensitivity Distribution (SSD) approach for estimating a spatially differentiated indicator of potential macroplastic entanglement impacts with global coverage of the world's oceans. This constitutes a key modelling step that contributes towards the inclusion of plastic litter effects in impact assessments. We gathered entanglement incidence data for 20 species of marine mammals, turtles and birds from different populations and marine regions. To capture species-specific sensitivities to entanglement and spatially varying concentrations of plastic debris, concentration–response modelling of field data was used to develop the SSD-based model. This was achieved by linking population specific entanglement records to corresponding regional areas of exposure and an existing global model of plastic debris concentrations. The SSD was further applied to derive an estimate of the Potentially Affected Fraction (PAF) of species on a global scale, highlighting regional hotspots of potential entanglement impacts at current levels of marine plastic pollution. This indicator can be adapted and applied in impact assessments in order to account for potential impacts of mismanaged plastic waste ending up in marine ecosystems. [ABSTRACT FROM AUTHOR]

Plastic in the environment is considered an emerging pollutant of global concern. In spite of intensive research, many questions remain open, such as the processes that drive the deposition and remobilization of plastic debris on river beaches. The objectives of this study were: i) to analyze the influence of the natural hydrological fluctuations and wind intensity on the distribution of mesoplastic (0.5–2.5 cm) and macroplastic (>2.5 cm) debris in beach sediments of a large river, ii) to describe the type of plastic debris found and iii) to explore potential relations between the number of items and weight of macro- and mesoplastics. Our results suggest that, during lowering water levels, flow removes the plastic debris and transports it further downstream. Conversely, when the beach sediments remain exposed during long periods, the plastic debris accumulates considerably. Nevertheless, the influence of wind intensity on plastic debris transport was comparatively negligible. In other words, in our study the water flow had a greater capacity to remobilize and transport plastic debris than the wind. The most abundant mesoplastic items were foam, hard plastic, film and small fragments of fishing line. The dominant macroplastic items recorded were pieces of fishing line (nylon) and cigarette filters (cellulose acetate), typically discarded by beach users. Other items found in large quantities were soft packaging elements (expanded polystyrene), hard plastic containers (polystyrene, polyethylene terephthalate) and beverage bottles (polyethylene terephthalate), typical items of domestic use in the Paraná River region. Finally, we found that the density of macroplastic items is highly correlated to the density of mesoplastic items, serving as surrogate for further estimations. Our results could help to develop better mitigation strategies in seasonal riverscapes, based on the influence of the hydrological cycle and the characteristics of the most abundant meso- and macroplastics. [Display omitted] • Hydrology plays a crucial role in the dynamics of plastic debris on river beaches. • The influence of wind intensity on plastic debris dynamics was minor. • Plastic debris tend to accumulate on river beaches during long periods of sediment exposition. • The dominant macroplastics were fishing lines, cigarette butts, packaging and bottles. • The density of macroplastic items can be used as surrogate for density of mesoplastic. [ABSTRACT FROM AUTHOR]

Despite recent advances in remote sensing of large accumulations of floating plastic debris, mainly in coastal regions, the quantification of individual macroplastic objects (>50 cm) remains challenging. Here, we have trained an object-detection algorithm by selecting and labeling footage of floating plastic debris recorded offshore with GPS-enabled action cameras aboard vessels of opportunity. Macroplastic numerical concentrations are estimated by combining the object detection solution with bulk processing of the optical data. Our results are consistent with macroplastic densities predicted by global plastic dispersal models, and reveal first insights into how camera recorded offshore macroplastic densities compare to micro- and mesoplastic concentrations collected with neuston trawls. [ABSTRACT FROM AUTHOR]

Plastic debris is globally found around the world and the remote Arctic is no exception. Arctic true seals are sentinel species of marine pollution and represent the link between marine food webs and Arctic apex predators like polar bears and humans. With regard to true seals, ingested macroplastics have never been reported in an Arctic species. We harvested 10 harp seals Pagophilus groenlandicus and 8 hooded seals Cystophora cristata from the breeding grounds in the pack ice of the Greenland Sea. The digestive tract was inspected exclusively for the presence of macroplastics (>5 mm). Two pieces of single-use plastic were found in the stomach of a weaned hooded seal pup. This study indicates that young Arctic marine predators may ingest macroplastics, and therefore may be at risk during their early stages of life due to human caused plastic pollution even in the remote Arctic pack ice. [Display omitted] • We found plastic debris in the stomach of an Arctic seal pup for the first time. • Debris consisted of two pieces of light single-use plastic. • Newborns of Arctic seals are at risk of exposure to plastic directly after weaning. • Ecotoxicological investigations of plastic exposure to Arctic wildlife are needed. [ABSTRACT FROM AUTHOR]

• Plastic policy was adapted due to COVID-19 pandemic. • COVID-19 pandemic is contributing to worldwide plastic pollution. • COVID-19 precautionary measures challenged environmental sustainability. • Sustainability calls for straightened links between policy-industry-research. Plastics have become a severe transboundary threat to natural ecosystems and human health, with studies predicting a twofold increase in the number of plastic debris (including micro and nano-sized plastics) by 2030. However, such predictions will likely be aggravated by the excessive use and consumption of single-use plastics (including personal protective equipment such as masks and gloves) due to COVID-19 pandemic. This review aimed to provide a comprehensive overview on the effects of COVID-19 on macroplastic pollution and its potential implications on the environment and human health considering short- and long-term scenarios; addressing the main challenges and discussing potential strategies to overcome them. It emphasises that future measures, involved in an emergent health crisis or not, should reflect a balance between public health and environmental safety as they are both undoubtedly connected. Although the use and consumption of plastics significantly improved our quality of life, it is crucial to shift towards sustainable alternatives, such as bio-based plastics. Plastics should remain in the top of the political agenda in Europe and across the world, not only to minimise plastic leakage and pollution, but to promote sustainable growth and to stimulate both green and blue- economies. Discussions on this topic, particularly considering the excessive use of plastic, should start soon with the involvement of the scientific community, plastic producers and politicians in order to be prepared for the near future. [ABSTRACT FROM AUTHOR]

Research into the scope of litter pollution in freshwater systems has shown similar levels to the marine and coastal environment. Global model estimates of riverine emission rates of anthropogenic litter are largely based on microplastic studies as long-term and holistic observations of riverine macroplastics are still scarce. This study therefore aims to contribute a detailed assessment of macrolitter in the transitional waters of three major North Sea tributaries: Ems, Weser, and Elbe. Litter surveys were carried out in four river compartments: along the embankment, on the river surface, in the water column, and on the river bed. The data revealed spatio-temporal variability and distinct pollution levels for each compartment. Beaches had the highest debris diversity and were significantly more littered than vegetated sites and harbors. Stony embankments were least polluted. Benthic litter levels appeared substantial despite rapid burial of objects being likely due to high suspended sediment loads. Two extrapolation approaches were tested to scale daily and annual litter emission quantities of surface- and subsurface-floating litter. Using the mean (median) litter item mass from water column samples, total annual mass discharges were calculated: ∼0.9 (0.2) t y−1 to ∼2.8 (0.5) t y−1 emitted via the Ems, ∼1.3 (0.2) t y−1 to ∼12.0 (1.9) t y−1 through the Weser, and ∼14.7 (2.4) t y−1 to ∼801 (128) t y−1 carried into the North Sea by the Elbe. These rates deviate considerably from previous model estimates of plastic loads discharged by these three rivers. Future studies should therefore ground-truth model estimates with more river-specific and long-term field observations. Overall, the estimated plastic debris discharge quantities account for <1% of the total mass of mismanaged plastic waste per catchment. Image 1 • Anthropogenic debris was holistically surveyed in the lower Ems, Weser, and Elbe. • Amounts varied between embankment type, river surface, water column, and river bed. • Observations generally confirmed larger rivers to have higher pollution levels. • Field-based litter outflow rates diverged from past model-based estimates. • Future studies should ground-truth model estimates with more field observations. [ABSTRACT FROM AUTHOR]

The paper presents a conceptual model of the route of macroplastic debris (>5 mm) through a fluvial system, which can support future works on the overlooked processes of macroplastic storage and remobilization in rivers. We divided the macroplastic route into (1) input, (2) transport, (3) storage, (4) remobilization and (5) output phases. Phase 1 is mainly controlled by humans, phases 2–4 by fluvial processes, and phase 5 by both types of controls. We hypothesize that the natural characteristics of fluvial systems and their modification by dam reservoirs and flood embankments construction are key controls on macroplastic storage and remobilization in rivers. The zone of macroplastic storage can be defined as a river floodplain inundated since the beginning of widespread disposal of plastic waste to the environment in the 1960s and the remobilization zone as a part of the storage zone influenced by floodwaters and bank erosion. The amount of macroplastic in both zones can be estimated using data on the abundance of surface- and subsurface-stored macroplastic and the lateral and vertical extent of the zones. Our model creates the framework for estimation of how much plastic has accumulated in rivers and will be present in future riverscapes. [ABSTRACT FROM AUTHOR]

Plastic debris presents a serious hazard to marine ecosystems worldwide. In this study, we developed a method to evaluate high-resolution maps of plastic emissions from the land into the sea offshore of Japan without using mismanaged plastic waste. Plastics were divided into microplastics (MicPs) and macroplastics (MacPs), and correlations between the observed MicP concentrations in rivers and basin characteristics, such as the urban area ratio and population density, were used to evaluate nationwide MicP concentration maps. A simple water balance analysis was used to calculate the annual outflow for each 1 km mesh to obtain the final MicP emissions, and the MacP input was evaluated based on the MicP emissions and the ratio of MacP/MicP obtained according to previous studies. Concentration data revealed that the MicP concentrations and basin characteristics were significantly and positively correlated. Water balance analyses demonstrated that our methods performed well for evaluating the annual flow rate, while reducing the computational load. The total plastic input (MicP + MacP) was widely distributed from 210–4776 t/yr and a map showed that plastic emissions were high for densely populated and highly urbanized areas in the Tokyo metropolitan area, as well as other large urban areas, especially Nagoya and Osaka. These results provide important insights that may be used to develop countermeasures against plastic pollution and the methods employed herein can also be used to evaluate plastic emissions in other regions. [ABSTRACT FROM AUTHOR]

Plastic pollution has been reported in sediment, surface water and biota of freshwater systems especially in Europe, North and South America, and Asia with limited studies focussing on African great lakes. This study therefore investigated the occurrence, abundance and distribution of micro-, meso- and macro-plastic debris along shores and sediment of northern Lake Victoria. The abundance of micro-, meso- and macro-plastics measured as particles/kg dry sediment were in range of 0–1102, 0–218 and 0–100 respectively in shoreline sediment and 0–108, 0–33 and 0–77 respectively in lake sediment. The mean abundance of micro-, meso- and macro-plastic debris at fish landing beaches (75.2 ± 50.0, 16.7 ± 8.1 and 18.1 ± 4.6 respectively) were higher than what was recorded at recreational beaches (1.5 ± 0.6, 3.1 ± 3.1 and 3.8 ± 3.8 respectively). Similarly, mean abundance of micro-, meso- and macro-plastic debris in lake sediment were higher in areas of fish landing beaches (9.5 ± 2.6, 2.1 ± 1.5 and 7.7 ± 4.5 respectively) than what was recorded in areas of recreational beaches (0.7 ± 0.7, 0.2 ± 0.1, and 0 ± 0 respectively). Films, filaments, fragments, foam and pellets were the plastic types, with the shoreline sediment dominated by films (>54%) while lake sediment was dominated by filaments (>55%), across size groups (micro-, meso- and macro-plastics). Spearman's rank correlation indicated strong and significant correlation between abundance of micro- and meso-plastics for total plastic, film plastic and fragment plastic in shoreline sediment. Significant correlation between macroplastics in shoreline sediment and microplastics in lake sediment for total plastics was observed. The FTIR analysis revealed that polyethylene, polypropylene, Polyethylene Terephthalate, Polyamide (nylon), and polyvinyl chloride were the major polymers. These results demonstrated that fish landing beaches along Lake Victoria are hotspot areas for plastic pollution of the lake and should therefore be targeted for management of plastic pollution of Lake Victoria. Image 1 • Plastic pollution of shores and sediment of Lake Victoria in East Africa was studied. • Abundance of plastic debris was highest at fish landing beaches and lowest at recreational beaches. • In most sites, microplastic abundance decreased with increasing distance from the shoreline into pelagic waters. • Film plastic type was dominant in shoreline sediment while filament type dominated in lake sediment. • There was a strong correlation between microplastics and mesoplastics in shoreline sediment. [ABSTRACT FROM AUTHOR]

Plastic pollution in aquatic ecosystems is an emerging environmental risk, as it may negatively impacts ecology, endangers aquatic species, and causes economic damage. Rivers are known to play a crucial role in transporting land‐based plastic waste to the world's oceans, but riverine ecosystems are also directly affected by plastic pollution. To better quantify global plastic pollution transport and to effectively reduce sources and risks, a thorough understanding of origin, transport, fate, and effects of riverine plastic debris is crucial. In this overview paper, we discuss the current scientific state on plastic debris in rivers and evaluate existing knowledge gaps. We present a brief background of plastics, polymer types typically found in rivers, and the risk posed to aquatic ecosystems. Additionally, we elaborate on the origin and fate of riverine plastics, including processes and factors influencing plastic debris transport and its spatiotemporal variation. We present an overview of monitoring and modeling efforts to characterize riverine plastic transport, and give examples of typical values from around the world. Finally, we present an outlook to riverine plastic research. With this paper, we aim to present an inclusive and comprehensive overview of riverine plastic debris research to date and suggest multiple ways forward for future research. This article is categorized under: Science of Water > Water QualityWater and Life > Stresses and Pressures on Ecosystems [ABSTRACT FROM AUTHOR]

In recent years, there is great concern about plastic pollution due to the identification of several environmental risks associated with microplastics (<5 mm). This study investigated microplastic and macroplastic accumulation patterns in a newly formed Spartina alterniflora colonized saltmarsh of an estuary in southeastern China. Abundance of microplastic and macroplastic particles was in the range of 9600–130725 and 200-4350 n/m2, respectively. Abundances of microplastics and macroplastics were highest at the saltmarsh edge, but the mass of macroplastics was highest in the saltmarsh interior. Mass of microplastics and macroplastics in bareflats was significantly lower than vegetated areas. Although microplastics accounted for 96.3% of total plastic abundance, macroplastics accounted for 90% of total plastic mass. Results showed that S. alterniflora dominated saltmarshes have a strong ability to trap plastic debris, especially macroplastics. Thus, coastal saltmarshes may serve as a transformer of macroplastics to microplastics and consequently as a source of microplastics to the ocean. Image 1 • Saltmarshes have a strong ability to trap plastic debris, especially macroplastics. • Reporting the mass of plastics is important for plastic pollution monitoring. • Degradation of macroplastics in saltmarshes may produce abundant microplastics. • Saltmarshes act as a sink for macroplastics and a source of microplastics to ocean. • Macroplastic removal from beaches is critical for reducing microplastic pollution. [ABSTRACT FROM AUTHOR]