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A comprehensive physicochemical characterization of heterogeneous nanoplastic (NPL) samples remains an analytical challenge requiring a combination of orthogonal measurement techniques to improve the accuracy and robustness of the results. Here, batch methods, including dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), as well as separation/fractionation methods such as centrifugal liquid sedimentation (CLS) and field-flow fractionation (FFF)–multi-angle light scattering (MALS) combined with pyrolysis gas chromatography mass spectrometry (pyGC–MS) or Raman microspectroscopy (RM) were evaluated for NPL size, shape, and chemical composition measurements and for quantification. A set of representative/test particles of different chemical natures, including (i) polydisperse polyethylene (PE), (ii) (doped) polystyrene (PS) NPLs, (iii) titanium dioxide, and (iv) iron oxide nanoparticles (spherical and elongated), was used to assess the applicability and limitations of the selected methodologies. Particle sizes and number-based concentrations obtained by orthogonal batch methods (DLS, NTA, TRPS) were comparable for monodisperse spherical samples, while higher deviations were observed for polydisperse, agglomerated samples and for non-spherical particles, especially for light scattering methods. CLS and TRPS offer further insight with increased size resolution, while detailed morphological information can be derived by electron microscopy (EM)–based approaches. Combined techniques such as FFF coupled to MALS and RM can provide complementary information on physical and chemical properties by online measurements, while pyGC–MS analysis of FFF fractions can be used for the identification of polymer particles (vs. inorganic particles) and for their offline (semi)quantification. However, NPL analysis in complex samples will continue to present a serious challenge for the evaluated techniques without significant improvements in sample preparation. Graphical abstract

A common task in oceanography is to model the vertical movement of particles such as microplastics, nanoparticles, mineral particles, gas bubbles, oil droplets, fish eggs, plankton, or algae. In some cases, the distribution of vertical rise or settling velocities of the particles in question can span a wide range, covering several orders of magnitude, often due to a broad particle size distribution or differences in density. This requires numerical methods that are able to adequately resolve a wide and possibly multi-modal velocity distribution. Lagrangian particle methods are commonly used for these applications. strength of such methods is that each particle can have its own rise or settling speed, which makes it easy to achieve a good representation of a continuous distribution of speeds. An alternative approach is to use Eulerian methods, where the partial differential equations describing the transport problem are solved directly with numerical methods. In Eulerian methods, different rise or settling speeds must be represented as discrete classes, and in practice only a limited number of classes can be included. Here, we consider three different examples of applications for a water-column model: positively buoyant fish eggs, a mixture of positively and negatively buoyant microplastics, and positively buoyant oil droplets being entrained by waves. For each of the three cases we formulate a model for the vertical transport, based on the advection-diffusion equation with suitable boundary conditions and in one case a reaction term. We give a detailed description of an Eulerian and a Lagrangian implementation of these models, and we demonstrate that they give equivalent results for selected example cases. We also pay special attention to the convergence of the model results with increasing number of classes in the Eulerian scheme, and the number of particles in the Lagrangian scheme. For the Lagrangian scheme, we see the 1/√Np convergence as expected for a Monte Carlo method, while for the Eulerian implementation, we see a second order (1/N2k) convergence with the number of classes.

Weakened EPS protection of algal cells contributing to the increased internalization of TiO2 nanoparticles was identified as the key mechanism for the enhanced toxicity of TiO2 nanoparticles under UV-B irradiation.

Ongoing efforts focus on quantifying plastic pollution and describing and estimating the related magnitude of exposure and impacts on human and environmental health. Data gathered during such work usually follows a receptor perspective. However, Life Cycle Assessment (LCA) represents an emitter perspective. This study examines existing data gathering and reporting approaches for field and laboratory studies on micro- and nanoplastics (MNPs) exposure and effects relevant to LCA data inputs. The outcomes indicate that receptor perspective approaches do not typically provide suitable or sufficiently harmonised data. Improved design is needed in the sampling, testing and recording of results using harmonised, validated and comparable methods, with more comprehensive reporting of relevant data. We propose a three-level set of requirements for data recording and reporting to increase the potential for LCA studies and models to utilise data gathered in receptor-oriented studies. We show for which purpose such data can be used as inputs to LCA, particularly in life cycle impact assessment (LCIA) methods. Implementing these requirements will facilitate proper integration of the potential environmental impacts of plastic losses from human activity (e.g. litter) into LCA. Then, the impacts of plastic emissions can eventually be connected and compared with other environmental issues related to anthropogenic activities. publishedVersion

This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in Environmental Science and Technology, copyright © American Chemical Society after peer review. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acs.est.0c03113 In this study, the effects of aged Ag and TiO2 NPs, individually and as a mixture, in wastewater relative to their pristine counterparts on the development of the copepod nauplii (Tisbe battagliai) were investigated. NP behavior in synthetic wastewater and seawater was characterized during aging and exposure. A delayed development and subsequent mortality was observed after 6 days of exposure to aged Ag NPs, with a 2-fold decrease in EC50 (316 μg/L) compared to pristine NPs (EC50 640 μg/L) despite the similar dissolved Ag concentrations measured for aged and pristine Ag NPs (441 μg/L and 378 μg/L, respectively). In co-exposures with TiO2 NPs, higher dissolved Ag levels were measured for aged NPs (238.3 μg/L) relative to pristine NPs (98.57 μg/L). Co-exposure resulted in a slight decrease (15%) in the Ag NP EC50 (270 μg/L) with a 1.9-fold increase in Ag NP retained within the organisms after depuration (2.82% retention) compared to Ag NP single exposures as measured with sp-ICP-MS suggesting that the particles are still bioavailable despite the heteroaggregation observed between Ag, Ti NPs and wastewater components. This study shows that the presence of TiO2 NPs can affect the stability and toxicity of Ag NPs in complex media that cannot be predicted solely based on ionic, total or nanoparticulate concentrations and the need for studying NP interactions in more complex matrices is highlighted.

Marine litter in the Arctic Basin is influenced by transport from Atlantic and Pacific waters. This highlights the need for harmonization of guidelines across regions. Monitoring can be used to assess temporal and spatial trends but can also be used to assess if environmental objectives are reached, for example, to evaluate the effectiveness of mitigation measures. Seafloor monitoring by trawling needs substantial resources and specific sampling strategies to be sufficiently robust to demonstrate changes over time. Observation and visual evaluation in shallow and deep waters using towed camera systems, remotely operated underwater vehicles, and submersibles are well suited for the Arctic environment. The use of imagery still needs to be adjusted through automation and image analyses, including deep learning approaches and data management, but will also serve to monitor areas with a rocky seafloor. We recommend developing a monitoring plan for seafloor litter by selecting representative sites for visual inspection that cover different depths and substrata in marine landscapes, and recording the litter collected or observed across all forms of seafloor sampling or imaging. We need better coverage and knowledge of status of seafloor litter for the whole Arctic and recommend initiatives to be taken for regions where such knowledge is lacking.

A wide range of weathering processes contributes to the degradation of plastic litter items which leads to the formation of microplastics that may be detrimental to marine ecosystems and the organisms inhabiting them. In this study, the impact of UV exposure on the degradation of clear polypropylene (CPP), black polypropylene (BPP), and polyethylene terephthalate (PET) packaging materials was investigated over a period of 6 weeks under dry air conditions representing the terrestrial environment. The exposure was conducted using differently sized and shaped samples at irradiation intensities of 65 W/m2 and 130 W/m2. Results indicated that UV irradiation led to changes in the properties of PET, BPP, and CPP that were proportional to the intensity delivered, leading to a higher level of mass loss, carbonyl indices, crystallinities, and microhardness in all polymer types at 130 W/m2 relative to 65 W/m2. However, material shape and size did not have a significant influence on any property for any of the test materials. Increased mass loss over time was accompanied by considerable increases in carbonyl index (CI) for both PPs. Clear PP (CPP) underwent the most severe degradation, resulting in the highest mass loss, increase in crystallinity, and CI. BPP was less degraded and modified by the UV irradiation than the CPP, indicating that the colorant, carbon black, provided some degree of protection to the bulk polymer material. PET was the least degraded of the three materials, suggesting this polymer type is more resistant to UV degradation. The differences in the degradation behaviours of the three test materials under dry environmental conditions indicate that the UV exposure history of plastic litter might play an important role in its potential for further degradation once it reaches the marine environment. Furthermore, analysis of samples exposed to UV in aqueous media reveals a more irregular set of trends for most material properties measured. Overall, the degree of degradation resulting from UV irradiation in dry environments was more pronounced than in aqueous environments, although the most significant property changes were observed for materials without previous UV exposure histories. Samples with previous UV histories showed higher resistance to further crystallinity changes, which appeared to be due to crosslinking in the pretreatment exposures inhibiting chain alignment into crystalline structures. The effect of solution medium was insignificant, although the presence of water allowed hydrolytic degradation to proceed simultaneously with UV degradation for PET. The reduction of CI in pretreated materials in the aqueous exposures, combined with the mass loss, suggest that the degraded surface layer erodes or products dissolve into surrounding solution medium, leaving a fresh surface of plastic exposed.

Fuzzy Cognitive Mapping (FCM) is a participatory modelling tool used to explore complex systems by facilitating interdisciplinary cooperation and integrating a variety of knowledge systems. Here FCM was used to explore marine microfiber pollution. Through individual interviews with representatives from the research, industry, water and environmental sectors, five stakeholder FCMs were developed and used to produce an aggregated community FCM in a stakeholder workshop. Stakeholder FCMs and the revised community FCM were used to compute how the modelled system reacted to changes under two scenarios developed during the stakeholder workshop; (i) Green Shift and (ii) increased textile consumption and production. Significant differences were observed in scenario results from the stakeholder-based models and the community-based model. For societal challenges characterized by unknowns around the problem and potential solutions, inclusion of a variety of knowledge systems through FCM and deliberation processes contribute to a more holistic picture of the system and its uncertainties.

Although irregular-shaped secondary microplastics (SMP) account for most MPs in marine environments, little is known about their effects on marine organisms. We investigated the embryotoxicity of polyvinyl chloride SMP and primary microplastics (PMP) to the marine medaka Oryzias melastigma using mortality, heart rate, hatching rates, hatching time and malformation as endpoints. This study aimed to determine the physical impacts of MPs and elucidate underlying mechanisms of physical MP toxicity through O2 flow determination and measuring the gene expression involved in embryonic development. PMP were purchased in powder form, while SMP were prepared by milling a pristine PVC plastic water pipe; both were sieved to a size range of 53–106 μm. For the 25 day exposure assay, fertilized O. melastigma eggs were randomly assigned to 6-well plates containing 15 embryos/well. Seawater leachates generated from the PMP and SMP were also studied to account for chemical toxicity. Exposure of marine medaka embryos to PMP and SMP caused a range of negative effects, including changes in heart rate, morphological abnormalities and malformation types. At high exposure concentrations, SMP shortened hatching time and induced more significant teratogenic effects on larvae relative to the PMP. Physical damage from SMP to the chorion surface appears to be the main toxicity mechanism, caused by their irregular shape and reduced aggregation relative to PMP. In contrast, real-time changes in oxygen demonstrated that hypoxia caused by greater PMP adsorption to the chorion surface contributes to their toxicity relative to SMP. Modulation of genes involved in hypoxia-response, cardiac development and hatching confirmed the toxicity mechanisms of PMP and SMP. The chemical contribution to observed toxicity was negligible. Our findings indicate that although PMP exposure can lead to measurable toxic effects, their use underestimates the threat of SMP and they do not necessarily represent the toxic mechanisms observed for SMP. Also see: https://micro2022.sciencesconf.org/426781/document, In MICRO 2022, Online Atlas Edition: Plastic Pollution from MACRO to nano

Plastic garbage patches at the ocean surface are symptomatic of a wider pollution affecting the whole marine environment. Sinking of plastic debris increasingly appears to be an important process in the global fate of plastic in the ocean. However, there is insufficient knowledge about the processes affecting plastic distributions and degradation and how this influences the release of additives under varying environmental conditions, especially in deep-sea environments. Here we show that in abiotic conditions increasing hydrostatic pressure inhibits the leaching of the heaviest organic additives such as tris(2-ethylhexyl) phosphate and diisononyl phthalate from polyethylene and polyvinylchloride materials, whereas deep-sea and surface marine prokaryotes promote the release of all targeted additives (phthalates, bisphenols, organophosphate esters). This study provides empirical evidences for more efficient additive release at the ocean surface than in deep seawater, where the major plastic burden is supposed to transit through before reaching the sediment compartment., Plastics are major marine pollutants, and while research suggests that they can release potential harmful additives into seawater, how environmental conditions influence this is unknown. Here the authors determine that byproducts released from microplastics are less under deep-sea conditions versus surface.

Microplastic (MP) has become ubiquitous in the marine environment. Its threat to marine organisms has been demonstrated under laboratory conditions, yet studies on wild populations still face methodological difficulties. We reviewed the methods used to separate MP from soft animal tissues and highlighted a lack of standardised methodologies, particularly critical for synthetic microfibres. We further compared enzymatic and a potassium hydroxide (KOH)-based alkaline digestion protocols on wild crabs (Carcinus aestuarii) collected from three coastal lagoons in the north Adriatic Sea and on laboratory-prepared synthetic polyester (PES) of different colour and polypropylene (PP). We compared the cost-effectiveness of the two methods, together with the potential for adverse quantitative or qualitative effects on MP that could alter the capability of the polymers to be recognised via microscopic or spectroscopic techniques. Only 5.5% of the 180 examined crabs contained MP in their gastrointestinal tracts, with a notably high quantitative variability between individuals (from 1 to 117 particles per individual). All MP found was exclusively microfibres, mainly PES, with a mean length (±SE) of 0.5 ± 0.03 mm. The two digestion methods provided comparable estimates on wild crabs and did not cause any visible physical or chemical alterations on laboratory-prepared microfibres treated for up to 4 days. KOH solution was faster and cheaper compared to the enzymatic extraction, involving fewer procedural steps and therefore reducing the risk of airborne contamination. With digestion times longer than 4 days, KOH caused morphological alterations of some of the PES microfibres, which did not occur with the enzymatic digestion. This suggests that KOH is effective for the digestion of small marine invertebrates or biological samples for which shorter digestion time is required, while enzymatic extraction should be considered as alternative for larger organisms or sample sizes requiring longer digestion times.

Wastewater treatment plants (WWTPs) serve as an important route of microplastics (MPs) to the environment. Therefore, more effective MPs sampling and detection methodologies, as well as a better understanding of their influence on MPs occurrence and distributions in WWTP effluents, are needed for better removal and control. In this work, the efficiency of a municipal WWTP to remove MPs was assessed by collecting samples from raw to tertiary effluent during a 12-month sampling campaign (season-based) using different sampling methods (containers, 24-h composite and large grab samples). MPs retrieved from different treatment units within the WWTP were identified and quantified using plastic/non-plastic staining followed by optical microscopy, SEM and μ-Raman microscopy. Overall, the mean removal efficiency of MPs in the WWTP was 97%, with most MPs removed by the secondary stage and a mean effluent concentration of 1.97 MPs L−1after sand filtration. The relative abundance of particles was lower than fibers in treated effluent compared with the raw wastewater, with MP fibers constituting 74% of the total MPs in raw wastewater and 91% in treated effluent. Taking seasonal variations into account is important as total MPs concentration in the effluent was notably higher in winter compared with the other seasons. Increasing the sampled volume using large samples or 24-h composite samples significantly reduced the variability between replicates. However, MPs concentration post the tertiary stage was significantly lower using morning sampling (9am) by large grab sampling method (1.2 MPs L−1) compared to 24-h composite sampling (3.2 MPs L−1) possibly due to intra-daily changes. Using a finer mesh size (0.45μm) to capture MPs beyond the size range typically studied (≥20μm) almost quadrupledthe number of MPs detected in the tertiary effluent and highlights the importance of standardizing sampling procedures.

Rare earth elements and yttrium (REY) are critical elements for a wide range of applications and consumer products. Their growing extraction and use can potentially lead to REY and anthropogenic-REY chemical complexes (ACC-REY) being released in the marine environment, causing concern regarding their potential effects on organisms and ecosystems. Here, we critically review the scientific knowledge on REY sources (geogenic and anthropogenic), factors affecting REY distribution and transfer in the marine environment, as well as accumulation in- and effects on marine biota. Further, we aim to draw the attention to research gaps that warrant further scientific attention to assess the potential risk posed by anthropogenic REY release. Geochemical processes affecting REY mobilisation from natural sources and factors affecting their distribution and transfer across marine compartments are well established, featuring a high variability dependent on local conditions. There is, however, a research gap with respect to evaluating the environmental distribution and fate of REY from anthropogenic sources, particularly regarding ACC-REY, which can have a high persistence in seawater. In addition, data on organismal uptake, accumulation, organ distribution and effects are scarce and at best fragmentary. Particularly, the effects of ACC-REY at organismal and community levels are, so far, not sufficiently studied. To assess the potential risks caused by anthropogenic REY release there is an urgent need to i) harmonise data reporting to promote comparability across studies and environmental matrices, ii) conduct research on transport, fate and behaviour of ACC-REY vs geogenic REY iii) deepen the knowledge on bioavailability, accumulation and effects of ACC-REY and REY mixtures at organismal and community level, which is essential for risk assessment of anthropogenic REY in marine ecosystems.

This paper presents the results of a computer analysis of the effect of activation process temperature on the development of the microporous structure of activated carbon derived from the leaves of common polypody (Polypodium vulgare) via chemical activation with phosphoric acid (H3PO4) at activation temperatures of 700, 800, and 900 °C. An unconventional approach to porous structure analysis, using the new numerical clustering-based adsorption analysis (LBET) method together with the implemented unique gas state equation, was used in this study. The LBET method is based on unique mathematical models that take into account, in addition to surface heterogeneity, the possibility of molecule clusters branching and the geometric and energy limitations of adsorbate cluster formation. It enabled us to determine a set of parameters comprehensively and reliably describing the porous structure of carbon material on the basis of the determined adsorption isotherm. Porous structure analyses using the LBET method were based on nitrogen (N2), carbon dioxide (CO2), and methane (CH4) adsorption isotherms determined for individual activated carbon. The analyses carried out showed the highest CO2 adsorption capacity for activated carbon obtained was at an activation temperature of 900 °C, a value only slightly higher than that obtained for activated carbon prepared at 700 °C, but the values of geometrical parameters determined for these activated carbons showed significant differences. The results of the analyses obtained with the LBET method were also compared with the results of iodine number analysis and the results obtained with the Brunauer–Emmett–Teller (BET), Dubinin–Radushkevich (DR), and quenched solid density functional theory (QSDFT) methods, demonstrating their complementarity.

A high proportion of the total microplastic (MP) load in the marine environment has been identified as microfibers (MFs), with polyester (PET) and polyamide (PA) typically found in the highest abundance. The potential for negative environmental impacts from MPs may be dependent on their degree of degradation in the environment, which is influenced by both intrinsic properties (polymer type, density, size, additive chemicals) and extrinsic environmental parameters. Most polymer products break down slowly through a combination of environmental processes, but UV degradation can be a significant source of degradation. The current study aimed to investigate the effect of UV irradiance on the degradation of natural (wool) and synthetic (PET and PA) MFs. Degradation of MFs was conducted in seawater under environmentally relevant accelerated exposure conditions using simulated sunlight. After 56 days of UV exposure, PA primarily exhibited changes in surface morphology with no significant fragmentation observed. PET and wool fibers exhibited both changes in surface morphology and fragmentation into smaller particles. A range of molecular degradation products were identified in seawater leachates after UV exposure, with increasing abundance over the duration of the experiment. Furthermore, a variety of additive chemicals were shown to leach from the MFs into seawater. While some of these chemicals were also susceptible to UV degradation and some are expected to biodegrade rapidly, others may be persistent and contribute to the overall load of chemical pollution in the marine environment. https://doi.org/10.1016/j.scitotenv.2020.143170 0048-9697/© 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Human exposure to nano- and microplastics (NMPs) has raised major societal concerns, yet no framework to assess the risks of NMPs for human health exists. A substantial proportion of plastic produced worldwide is not properlydisposed and persists in the environment for decades while degrading. Plastic degradation generates a size continuum of fragments, including nano- and microplastic particles, with numerous associated environmentalpollutants and plastic additives, and microbial communities colonising their surfaces. The ubiquitous presence of NMPs, their availability for uptake by organisms and their potential to act as vectors for toxicants and pathogensrender risk assessment a priority on the political agenda at the global level. We provide a new, fully integrated riskassessment framework tailored to the specificities of NMPs, enabling an assessment of current and future human health risks from NMPs. The framework consists of four novel paradigms to the traditional risk assessmentmethodology. These paradigms deal with techniques in NMP analysis, gaps in empirical data, theoretical and modelling approaches and stakeholder engagement. Within the proposed framework, we propose how we can useresearch experiences gained so far to carry out the different steps of the assessment process, and we define priorities for further research.Keywords: Microplastics, nanoplastics, risk assessment, human health, hazard identification, exposure assessment, hazard characterization, stakeholder engagement, food, air

In this study, we conducted and documented workshops and interviews in Norway and Slovenia to identify stakeholder and future generation opinions and mitigation strategies for solving one of the most prominent environmental issues: plastic pollution. As part of the EU H2020 project GoJelly, stakeholders were brought together to explore their perceptions on considering jellyfish mucus as a new resource to contribute to reducing plastic pollution from entering the marine environment. The study was conducted in the spring of 2019, in a context directly after the European Union (EU) announced its Directive to ban the most commonly used single-use plastic (SUP) items. The study applied the snowball method as a methodological choice to identify relevant stakeholders. Systems thinking was utilized as a participatory modelling approach, which allowed for the creation of conceptual mind maps from the various workshops and interviews, to understand consumers’ consciousness, and to map out ideas on plastic pollution reduction. Plastic pollution takes place on a global scale and stakeholders discussed their individual perceptions of national and international solutions that could be put in place to solve it, including the opportunities around utilizing jellyfish mucus to filter and capture micro- and nanoplastic. We found that industry stakeholders in both case areas were generally more accepting of policy and increased innovation moving forward, but placed weight on the scientific community to conduct more research on the pollution issue and propose solutions. Future generation stakeholders (youth aged 14–18), however, put emphasis on consumer behavior and buying patterns of single-use products fueling the plastic crisis.

Microplastics (MPs; particles5 mm) are widely distributed in various habitats from the land to the oceans. They have even reached the remotest of places, including the deep seas and Polar Regions. Although research on MPs pollution in the marine environment has received widespread attention in recent years, the distribution, sources and ecological risks of MPs in coastal areas remain unclear. This study assessed the abundance, characteristics, sources and ecological risk of MPs in surface waters and sediment of the mainland coast and four island groups comprising the coral reef environment of the Gulf of Mannar (GoM), southeast India. Mean MPs abundance across all 95 sampling sites ranged from 28.4 to 126.6 items L

This chapter presents an overview of the knowledge on the impacts and toxicity of particulate plastics to a range of marine functional groups, including both acute and sub-lethal endpoints. A laboratory study on plastic leachates showed differential toxicity to the harpacticoid copepod Nitocra spinipes depending on the plastic product and the simulated weathering conditions applied. The potential toxicity of plastic additives, therefore, depends on the concentration of the additive, the residence time in the ingesting organism, and external factors, such as prey and background concentrations of the target contaminant. Plastic particles undergo a number of transformations after they enter the marine environment, which influence their pathways and behavior within food webs. Plastic exposed to marine conditions starts degrading, and, although this process is generally slow, the surface structure of the material changes, becomes more brittle and cracked, and provides a habitat for microbes and rafting organisms.

Crumb rubber granulate (CRG) produced from end of life tires (ELTs) is commonly applied to synthetic turf pitches (STPs), playgrounds, safety surfaces and walkways. In addition to fillers, stabilizers, cross-linking agents and secondary components (e.g., pigments, oils, resins), ELTs contain a range of other organic compound and heavy metal additives. While previous environmental impact studies on CRG have focused on terrestrial soil and freshwater ecosystems, many sites applying CRG in Norway are coastal. The current study investigated the organic chemical and metal additive content of ‘pristine’ and ‘weathered’ CRG and their seawater leachates, as well as uptake and effects of leachate exposure using marine copepods (Acartia and Calanus sp.). A combination of pyrolysis gas chromatography mass spectrometry (py-GC-MS) and chemical extraction followed by GC-MS analysis revealed similar organic chemical profiles for pristine and weathered CRG, including additives such as benzothiazole, N-1,3-dimethylbutyl-N′-phenyl-p-phenylenediamine and a range of polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds (e.g., bisphenols). ICP-MS analysis revealed g kg–1 quantities of Zn and mg kg–1 quantities of Fe, Mn, Cu, Co, Cr, Pb, and Ni in the CRG. A cocktail of organic additives and metals readily leached from the CRG into seawater, with the most abundant leachate components being benzothiazole and Zn, Fe, Co (metals), as well as detectable levels of PAHs and phenolic compounds. Concentrations of individual components varied with CRG source material and CRG to seawater ratio, but benzothiazole and Zn were typically the organic and metal components present at the highest concentrations in the leachates. While organic chemical concentrations in the leachates stabilized within days, metals continued to leach out over the 30-day period. Marine copepods exposed to high CRG leachate concentrations exhibited high mortalities within 48 h. The smaller lipid-poor Acartia had a higher sensitivity to leachates than the larger lipid-rich Calanus, indicating species-specific differences in vulnerability to leachates. The effect on survival was alleviated at lower leachate concentrations, indicating a dose-response relationship. Benzothiazole and its derivatives appear to be of concern owing to their proven toxicity, while bisphenols are also known to be toxic and were enriched in the leachates relative to the other compounds in the CRG.

Wastewater treatment plants (WWTPs) are a focal point for the removal of microplastic (MP) particles before they are discharged into aquatic environments. WWTPs are capable of removing substantial quantities of larger MP particles but are inefficient in removing particles with any one dimension of less than 100 μm, with influents and effluents tending to have similar quantities of these smaller particles. As a single WWTP may release >100 billion MP particles annually, collectively WWTPs are significant contributors to the problem of MP pollution of global surface waters. Currently, there are no policies or regulations requiring the removal of MPs during wastewater treatment, but as concern about MP pollution grows, the potential for wastewater technologies to capture particles before they reach surface waters has begun to attract attention. There are promising technologies in various stages of development that may improve the removal of MP particles from wastewater. Better incentivization could speed up the research, development and adoption of innovative practices. This paper describes the current state of knowledge regarding MPs, wastewater and relevant policies that could influence the development and deployment of new technologies within WWTPs. We review existing technologies for capturing very small MP particles and examine new developments that may have the potential to overcome the shortcomings of existing methods. The types of collaborations needed to encourage and incentivize innovation within the wastewater sector are also discussed, specifically strong partnerships among scientific and engineering researchers, industry stakeholders, and policy decision makers.

Many small- or medium-sized communities in Northern Europe employ only primary wastewater treatment plants (WWTPs) and effluent discharges can be a relevant source of pollution. The current study combines monitoring and modelling approaches to investigate concentrations, influent patterns, size distribution and removal of 20 elements for the two primary WWTPs (Ladehammeren, LARA; Høvringen, HØRA) serving Trondheim, the third largest city in Norway. Element concentrations were determined in raw influent wastewater, effluents and biosolids, and diurnal inflow patterns were assessed. The elemental distribution in particulate, colloidal and dissolved fractions of untreated wastewater was characterized using filtration separation and electron microscopy. An influent generator model and multivariate statistical analyses were used to determine release patterns and to predict the (co-)occurrence of selected elements. Raw influent wastewater concentrations for most elements were similar in the two WWTPs, with only Ca, Mn, Fe, Co and Ba being significantly higher (p

Microplastic fibres (MPFs) often make up the largest fraction of microplastic pollution in aquatic environments, yet little is known about their degradative fate and persistence. This study investigates the environmentally relevant photodegradation of common MPFs: polyester (PET), polyamide (PA) and polyacrylonitrile (PAN), their respective additive chemical profile, together with their potential for additive leaching. MPFs were subject to ultraviolet (UV) exposure in seawater and freshwater media over 10 months. PET and PA MPFs showed significant fragmentation and surface changes following UV exposure, additionally PA showed evidence of chemical changes. PAN did not undergo significant photodegradation in the same exposure period. Chemicals tentatively identified in MPFs and aqueous leachates via non-target gas chromatography-mass spectrometry include monomers, UV stabilisers and degradation products. Characterisation of several bisphenols (BPs) and benzophenones (BzPs) was performed via ultraperformance liquid chromatography tandem mass spectrometry. Bisphenol A, bisphenol S and benzophenone-3 were quantified in all MPFs and wool at concentrations between 4.3 - 501 ng/g, with wool displaying the highest sum concentration of BPs and BzPs at 863 and 27 ng/g, respectively. This is an open access article distributed under the terms of the Creative Commons CC-BY license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Re-use restricted to non-commercial and no derivative uses. The ubiquitous pollution of the environment with microplastics - a diverse suite of contaminants - is of growing concern for science and currently receives considerable public, political, and academic attention. The potential impact of microplastics in the environment has prompted a great deal of research in recent years. Many diverse methods have been developed to answer different questions about microplastic pollution, from sources, transport, and fate in the environment, and about effects on humans and wildlife. These methods are often insufficiently described, making studies neither comparable nor reproducible. The proliferation of new microplastic investigations and cross-study syntheses to answer larger scale questions are hampered. We - a diverse group of 23 researchers - think these issues can begin to be overcome through the adoption of a set of reporting guidelines. This collaboration was created using an open science framework that we detail for future use. Here, we suggest harmonized reporting guidelines for microplastic studies in environmental and laboratory settings through all steps of a typical study, including best practices for reporting materials, quality assurance / quality control, data, field sampling, sample preparation, microplastic identification, microplastic categorization, microplastic quantification, and considerations for toxicology studies. We developed three easy to use documents - a detailed document, a checklist, and a mind map - that can be used to quickly reference the reporting guidelines. It is our intention that these reporting guidelines support the annotation, dissemination, interpretation, reviewing, and synthesis of microplastic research. Through open access licensing (CC BY 4.0), these documents aim to increase the validity, reproducibility, and comparability of studies in this field for the benefit of the global community.

Microplastic fibers (MPFs) from textiles significantly contribute to the microplastic (MP) load in many environmental matrices and have been shown to negatively impact the organisms therein. Most fate and effect studies to date rely on pristine reference MP materials that have limited relevance compared with the partially degraded MP particles and fibers typically present in the natural environment. The current study aimed to develop and validate a rapid method to generate environmentally relevant polyester (PET) MPF reference material with controllable levels of degradation. Importantly, the method produced the same degradation products (terephthalic acid (TA) and ethylene glycol (EG)) as those generated during natural UV (sunlight) exposure of PET. Alkaline hydrolysis provided linearly increasing degrees of degraded PET MPFs over just a few hours, with full decomposition into molecular fragments occurring after 3 h. The extent of physical degradation was determined by scanning electron microscopy, whereas chemical degradation was quantified by measuring the production of TA and EG degradation products. The proposed accelerated hydrolysis degradation method is relevant for producing partially degraded PET MPF reference materials for use in fate and effect studies.

While it is likely that ENPs may occur together with other contaminants in nature, the combined effects of exposure to both ENPs and environmental contaminants are not studied sufficiently. In this study, we investigated the acute and sublethal toxicity of PVP coated silver nanoparticles (AgNP) and ionic silver (Ag+; administered as AgNO3) to the marine copepod Calanus finmarchicus. We further studied effects of single exposures to AgNPs (nominal concentrations: low 15 μg L−1 NPL, high 150 μg L−1 NPH) or Ag+ (60 μg L−1), and effects of co-exposure to AgNPs, Ag+ and the water-soluble fraction (WSF; 100 μg L−1) of a crude oil (AgNP + WSF; Ag++WSF). The gene expression and the activity of antioxidant defense enzymes SOD, CAT and GST, as well as the gene expression of HSP90 and CYP330A1 were determined as sublethal endpoints. Results show that Ag+ was more acutely toxic compared to AgNPs, with 96 h LC50 concentrations of 403 μg L−1 for AgNPs, and 147 μg L−1 for Ag+. Organismal uptake of Ag following exposure was similar for AgNP and Ag+, and was not significantly different when co-exposed to WSF. Exposure to AgNPs alone caused increases in gene expressions of GST and SOD, whereas WSF exposure caused an induction in SOD. Responses in enzyme activities were generally low, with significant effects observed only on SOD activity in NPL and WSF exposures and on GST activity in NPL and NPH exposures. Combined AgNP and WSF exposures caused slightly altered responses in expression of SOD, GST and CYP330A1 genes compared to the single exposures of either AgNPs or WSF. However, there was no clear pattern of cumulative effects caused by co-exposures of AgNPs and WSF. The present study indicates that the exposure to AgNPs, Ag+, and to a lesser degree WSF cause an oxidative stress response in C. finmarchicus, which was slightly, but mostly not significantly altered in combined exposures. This indicated that the combined effects between Ag and WSF are relatively limited, at least with regard to oxidative stress. DOI:10.1016/j.aquatox.2020.105582 Available online 24 July 2020 0166-445X/ © 2020 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/BY/4.0/).

For this study, the transfer of plastic additives to stomach oil of northern fulmars (Fulmarus glacialis) has been investigated. Procellariiform seabirds retain oily components of their prey in theirs stomach as a means to store energy. A marine litter-derived microplastic reference mixture and separately a marine litter-derived polystyrene sample were added to stomach oils in an experiment. A total of 15 additives, including plasticizers, antioxidants, UV stabilizers, flame retardants, and preservatives, were identified in the original plastic mixtures and monitored in the leachates. These substances include those known for endocrine disruptive, carcinogenic, and/or other negative effects on organisms. Stomach oil was exposed to these plastic materials and was sampled during a long-term experiment (0, 14, and 90 days’ exposure of plastic particles in stomach oil) and a subsequent short-term detailed study (8 h and 1, 2, 4, 8, and 21 days). Five of the monitored substances were shown to strongly leach from the microplastic reference mixture into the stomach oil during the experiment. Four substances were identified in a marine litter-derived polystyrene foam, of which two leached into stomach oil. Leaching of harmful plastic additives to the stomach oil of fulmars may be of concern, as fulmars regularly ingest plastics that are retained and gradually ground in the gizzard before passage to the intestines and excretion.

As reservoirs for pollutants transported via the Yangtze and Yellow Rivers, the Bohai Sea (BS) and Yellow Sea (YS) play an important role in transporting microplastics (MPs) to the Pacific Ocean. The fate, sources and mass budget of MPs in the BS and the YS were investigated by Pearson correlation, principal component analysis-multilinear regression analysis (PCA-MRLA) and a mass balance model to sedimentary MPs data. Average MP abundances were 137 and 119 items kg

Studies investigating the effects of plastic litter on marine biota have almost exclusively utilised pristine plastic materials that are homogeneous in polymer type, size, shape and chemical composition. This is particularly the case for microplastics (< 5 mm), where collecting sufficient quantities from the marine environment for use in laboratory impacts studies is simply not feasible. Weathered plastics collected from the marine environment show considerable physical and chemical differences to pristine and post-production consumer plastics. For this study, macroplastic litter was collected on a Dutch beach and cryo-milled to create a microplastic mixture for environmental impact assessments. The sample composition followed proportions of marine plastic litter types observed in an earlier large beach clean-up. Polymer composition of the sample was assessed by infrared spectroscopy (ATR-FTIR) and differential scanning calorimetry analysis (DSC). The particle size distribution of the cryo-milled microplastics showed that particles 0.5-2.0 mm represented 68% of mass, but smaller sizes (< 2 mm) strongly dominated numerically. Inductively coupled plasma spectroscopy (ICP-MS and ICP-OES) analysis of the microplastic mixture revealed a broad range of metals and other elements (e.g. Al, Cd, Cr, Fe, Mg, Pb, S and Zn), representing common inorganic additives used as colorants, fillers and stabilisers. GC-MS analysis identified a broad range of organic plasticisers, stabilisers, antioxidants and flame retardants. Comparison of different analytical approaches showed that creation of a homogeneous microplastic mixture is possible, representing a first step in closing the gap between laboratory studies with pristine materials and realistic scenarios with weathered microplastic. Marine microplastic: Preparation of relevant test materials for laboratory assessment of ecosystem impacts Susanne Kühn is funded through the Joint Program Initiative (JPI) Oceans PLASTOX (Direct and indirect ecotoxicological impacts of microplastics on marine organisms) project by the Netherlands Organisation for Scientific Research (NWO) under the project number ALW-NWO 856.15.001. SINTEF Ocean was funded through the JPI Oceans project PLASTOX by Research Council of Norway (RCN; Grant Agreement number 257479/E40). The authors wish to thank the NWO and the RCN for their financial support. We are very grateful for the assistance in the labs provided by Markus Ortlieb (Shimadzu), Marianne Kjos and Lisbet Sørensen (SINTEF) as well as Andre Bouwmeester, Stephanie Westerhoff and Erwin Jansen (Carat GmbH). Two anonymous reviewers provided valuable comments to improve earlier versions of the manuscript.

The dispersion behavior of carbon nanotubes (CNTs) is influenced by both their physicochemical properties and by the aqueous media properties (e.g. ionic strength, presence of divalent cations and natural organic matter) in which they are dispersed. In the current study, the dispersibility and dispersion stability of four multi-walled CNTs (MWCNT) and a single walled CNT (SWCNT) with different physicochemical properties were investigated in three freshwater growth media (with and without natural organic matter; NOM) used in algae and daphnia ecotoxicity studies. CNT dispersion behavior was also investigated in a natural freshwater for comparison. SWCNTs and non-functionalized MWCNTs showed similar dispersibility irrespective of the media type (SWCNTs = 0.5-0.9 mg/L; MWCNTs = 1.5-2.8 mg/L). Functionalized MWCNTs exhibited higher dispersion concentrations, but were more dependent upon the ionic strength and divalent cation concentration of each media (MWCNT-COOH = 3.0-6.6 mg/L). In contrast, CNT surface oxygen content had no influence on CNT dispersibility in the natural water (all MWCNTs = 0.9-1.4 mg/L). Functionalized MWCNTs were affected more by the differences in media properties than non-functionalized MWCNTs. The dispersed CNT concentration decreased over time for all CNT types and in all media due to sedimentation, but was influenced by both CNT and media properties. The study shows how a complex interplay between CNT and media properties can influence the environmental fate of CNTs. Furthermore, the study demonstrates how different CNT types and/or ecotoxicological media in aquatic tests influences the dispersion behavior of the CNTs, and thus their exposure and toxicity to aquatic organisms. Dispersibility and dispersion stability of carbon nanotubes in synthetic aquatic growth media and natural freshwater

Salt marshes in urban watersheds are prone to microplastics (MP) pollution due to their hydrological characteristics and exposure to urban runoff, but little is known about MP distributions in species from these habitats. In the current study, MP occurrence was determined in six benthic invertebrate species from salt marshes along the North Adriatic lagoons (Italy) and the Schelde estuary (Netherlands). The species represented different feeding modes and sediment localisation. The 96% of the analysed specimens (330) did not contain any MP, which was consistent across different regions and sites. Suspension and facultative deposit-feeding bivalves exhibited a lower MP occurrence (0.5-3%) relative to omnivores (95%) but contained a much more variable distribution of MP sizes, shapes and polymers. The study provides indications that MP physicochemical properties and species' ecological traits could all influence MP exposure, uptake and retention in benthic organisms inhabiting European salt marsh ecosystems.