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Aim: Although the incidence of mental health problems is highest in young people, the majority do not seek help. Reducing the discrepancy between need for care and access to services requires an understanding of the user perspective, which is largely lacking. This study aimed to examine preferences for mental health service attributes and their relative importance among young people, as well as the potential impact on actual help-seeking intentions., Methods: Youth aged 16-24 years (N = 258) participated in a discrete choice experiment. In addition to choosing which service would suit their needs most out of two service options in nine choice sets, participants were asked whether they would consult the chosen service in the case of mental health problems. Demographic information was also collected, as well as their current mental health status, experience with and perceived barriers to care. Panel mixed logit models were estimated., Results: Young people's preferences were mostly driven by the attribute 'format', with a preference for individual rather than group therapy. Other attributes, in order of importance, were 'wait times' (short), 'cost' (low), 'healthcare professionals' expertise' (particular experience with working with youth aged 12 to 25 years), and 'location' (house in a city). However, a majority of young people would not consult the service they had indicated, mainly due to attitudinal barriers such as wanting to deal with problems on their own (self-reliance)., Conclusions: Addressing psychological barriers to access care should be a priority in mental health policies. Furthermore, entry point services, in particular, should be able to provide the option of individual treatment., (© 2024 John Wiley & Sons Australia, Ltd.)

Coastal destinations are highly popular for leisure, yet the effects of spending time at the coast on mental and physical health have remained underexplored. To accelerate the research about the effects of the coast on health, we compiled a dataset from a survey on a sample (N = 1939) of the adult Flemish population about their visits to the Belgian coast. The survey queried the number of days spent at the coast in the previous year or before and the following characteristics of their visits: how often they performed specific activities, which of the 14 municipal seaside resorts they visited, who they were with, what they mentally and physically experienced, and what reasons they had for not visiting the coast more often. The respondents' geo-demographic (including residential proximity to the coast), socio-economic, and health profile was also collected. We anticipate that investigations on the data will increase our understanding about the social structuring of coastal visits and give context to the effects of the coast on human health., (© 2024. The Author(s).)

To better understand the fate and assess the ingestible fraction of microplastics (by aquatic organisms), it is essential to quantify and characterize of their released from larger items under environmental realistic conditions. However, the current information on the fragmentation and size-based characteristics of released microplastics, for example from bio-based thermoplastics, is largely unknown. The goal of our work was to assess the fragmentation and release of microplastics, under ultraviolet (UV) radiation and in seawater, from polylactic acid (PLA) items, a bio-based polymer, and from polypropylene (PP) items, a petroleum-based polymer. To do so, we exposed pristine items of PLA and PP, immersed in filtered natural seawater, to accelerated UV radiation for 57 and 76 days, simulating 18 and 24 months of mean natural solar irradiance in Europe. Our results indicated that 76-day UV radiation induced the fragmentation of parent plastic items and the microplastics (50 - 5000 µm) formation from both PP and PLA items. The PP samples (48 ± 26 microplastics / cm 2 ) released up to nine times more microplastics than PLA samples (5 ± 2 microplastics / cm 2 ) after a 76-day UV exposure, implying that the PLA tested items had a lower fragmentation rate than PP. The particles' length of released microplastics was parameterized using a power law exponent (α), to assess their size distribution. The obtained α values were 3.04 ± 0.11 and 2.54 ± 0.06 (-) for 76-day UV weathered PP and PLA, respectively, meaning that PLA microplastics had a larger sized microplastics fraction than PP particles. With respect to their two-dimensional shape, PLA microplastics also had lower width-to-length ratio (0.51 ± 0.17) and greater fiber-shaped fractions (16%) than PP microplastics (0.57 ± 0.17% and 11%, respectively). Overall, the bio-based PLA items under study were more resistant to fragmentation and release of microplastics than the petroleum-based PP tested items, and the parameterized characteristics of released microplastics were polymer-dependent. Our work indicates that even though bio-based plastics may have a slower release of fragmented particles under UV radiation compared to conventional polymer types, they still have the potential to act as a source of microplastics in the marine environment, with particles being available to biota within ingestible size fractions, if not removed before major fragmentation processes., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors Elke Demeyer is employed by Centexbel (Ghent, BE), a private company highly active in the knowledge transfer of textile and plastic processing industry. The other authors report no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The ubiquitous human exposure to nanoplastics (NPs) increasingly raises concerns regarding impact on our health. However, little is known on the biological effects of complex mixtures of weathered NPs with heterogenous size and irregular shape present in the environment. In this study, the bioenergetic effects of four such NPs mixtures on human intestinal Caco-2 cells were investigated. To this aim, Caco-2 cells were exposed to polydisperse nanoPET (<800 nm) and nanoPS (mixture of 100 and 750 nm) samples with and without ultraviolet (UV) weathering at low concentration range (10 2 -10 7 particles/mL) for 48 h. Mitochondrial respiration, glycolytic functions and ATP production rates of exposed cells were measured by Seahorse XFe96 Analyzer. Among four NPs samples, polydisperse nanoPET with irregular shapes induced significant stimulation of mitochondrial respiration, glycolysis and ATP production rates in Caco-2 cells. Spherical nanoPS caused significant stimulation on glycolytic functions of Caco-2 cells at the highest concentration used (10 6 particles/mL). ATR-FTIR spectra and carbonyl index indicated formation of carbonyl groups in nanoPET and nanoPS after UV weathering. UV weathering could alleviate bioenergetic stress caused by NPs in Caco-2 cells and even shifted the energy pathways from mitochondrial respiration to glycolysis due to electrostatic repulsion between negatively charged UV-aged NPs and cell membranes. This research is the first to study in-vitro bioenergetic responses of NPs samples with multidimensional features (polymer type, irregular shape, heterogenous size, UV-weathering) on human health. It highlights that effects between pristine and weathered NPs are different at a bioenergetic level, which has important implications for the risk assessment of NPs on human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The biofouling of submerged surfaces such as ship hulls is often prevented by using anti-fouling components in combination with booster biocides. These booster biocides enter the water column and may affect non-target organisms. Although different negative effects have been associated with the use of booster biocides, their effects on non-target organisms are often unknown. So far, the environmental risks for booster biocides have barely been quantified in the North Sea. In this work, the concentration of five commonly used booster biocides as well as tributyltin has been monitored at five dredged spoil disposal sites in the Belgian part of the North Sea and the harbour and ports of Nieuwpoort, Oostende, and Zeebrugge. Hotspots were discovered where the concentration of one or more booster biocides exceeded the predicted no-effect concentration. Tributyltin has been banned since 2008, but concentrations of 237- to 546-fold of the predicted no-effect concentration were detected in the harbours and ports. Moreover, TBT has been detected in the same order of magnitude in other sea basins, emphasizing the need to monitor the trends and impact of booster biocides and TBT in environmental monitoring programs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Introduction: Although youth-friendly service characteristics have been previously identified, consensus among a representative group of stakeholders about which of these characteristics are truly relevant to the youth-friendliness of services is currently lacking. In our study, young adults, parents and professionals were consulted on this topic to reveal existing (dis)agreement. In addition, (dis)agreement on feasibility for implementation in clinical practice was also assessed., Methods: A mixed-method Delphi approach was used with three online questionnaire rounds and a physical meeting. Young adults (18-26 years) and parents were part of a public panel and professionals were allocated to the professional panel. In the rounds, participants were asked to rate the importance and feasibility of each item. Subsequently, the percentage agreement (% of participants giving a score of 7 or above on a 9-point Likert scale) within and across panels was calculated. Consensus was assumed to have been reached when at least 70% agreement was achieved. A thematic analysis of the qualitative data, obtained in the rounds and the physical meeting, was performed to identify overarching themes and characteristics of relevance to the youth-friendliness of services., Results: For 65% of the items included in the Delphi questionnaire, consensus on importance was reached within both panels. Participants showed more insecurity about the feasibility of these items, however. Our thematic analysis revealed reasons for disagreement between and within the panels., Conclusions: Our study revealed substantial between- and within-panel agreement on youth-friendly service characteristics. We recommend that the items for which consensus was reached should be used as a checklist in terms of youth mental health service development, design and delivery. The characteristics for which there was disagreement between and within the panels should inspire an ongoing trialogue between young adults, parents and professionals both on the individual level and the service level., Patient or Public Contribution: In this study, (parents of) young adults with lived experience were included as experts, including one of the coauthors. This coauthor contributed to the manuscript by having a final say about the included quotes., (© 2023 The Authors. Health Expectations published by John Wiley & Sons Ltd.)

Sea spray has been suggested to enable the transfer of micro- and nanoplastics (MNPs) from the ocean to the atmosphere, but only a few studies support the role of sea spray aerosols (SSAs) as a source of airborne particles. We demonstrated that MNPs are aerosolized during wave action, via SSAs, under controlled laboratory conditions. We used a mini-Marine-Aerosol-Reference-Tank (miniMART), a device that mimics naturally occurring physical mechanisms producing SSAs, and assessed the aerosolization of fluorescent polystyrene beads (0.5-10 μm), in artificial seawater. The SSAs contained up to 18,809 particles/mL of aerosols for 0.5 μm beads, with an enrichment factor of 19-fold, and 1977 particles/mL of aerosols for 10 μm beads with a 2-fold enrichment factor. Our study demonstrates that the use of the miniMART is essential to assess MNPs aerosolization in a standardized way, supporting the hypothesis which states that MNPs in the surface of the ocean may be transferred to the atmosphere., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Plastic pollution is both a societal and environmental problem and citizen science has shown to be a useful tool to engage both the public and professionals in addressing it. However, knowledge on the educational and behavioral impacts of citizen science projects focusing on marine litter remains limited. Our preregistered study investigates the impact of the citizen science project Citizen Observation of Local Litter in coastal ECosysTems (COLLECT) on the participants' ocean literacy, pro-environmental intentions and attitudes, well-being, and nature connectedness, using a pretest-posttest design. A total of 410 secondary school students from seven countries, in Africa (Benin, Cabo Verde, Côte d'Ivoire, Ghana, Morocco, Nigeria) and Asia (Malaysia) were trained to sample plastics on sandy beaches and to analyze their collection in the classroom. Non-parametric statistical tests ( n  = 239 matched participants) demonstrate that the COLLECT project positively impacted ocean literacy (i.e., awareness and knowledge of marine litter, self-reported litter-reducing behaviors, attitudes towards beach litter removal). The COLLECT project also led to higher pro-environmental behavioral intentions for students in Benin and Ghana (implying a positive spillover effect) and higher well-being and nature connectedness for students in Benin. Results are interpreted in consideration of a high baseline in awareness and attitudes towards marine litter, a low internal consistency of pro-environmental attitudes, the cultural context of the participating countries, and the unique settings of the project's implementation. Our study highlights the benefits and challenges of understanding how citizen science impacts the perceptions and behaviors towards marine litter in youth from the respective regions., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Severin, Akpetou, Annasawmy, Asuquo, Beckman, Benomar, Jaya-Ram, Malouli, Mees, Monteiro, Ndwiga, Neves Silva, Nubi, Sim, Sohou, Shau-Hwai, Woo, Zizah, Buysse, Raes, Krug, Seeyave, Everaert, Mahu and Catarino.)

The global presence of plastic litter and its accumulation in the environment has become an issue of concern to the public and policymakers. This concern has triggered innovators in past decades to design and develop a multitude of remediation technologies to prevent plastic from entering the environment, or to clean up legacy litter. This study aims to (i) systematically review the current scientific literature on plastic remediation technologies, (ii) create a 'plastic clean-up and prevention overview' illustrating 124 remediation technologies and 29 characteristics, (iii) qualitatively analyse their key characteristics (e.g., fields of application, targeted plastic), and (iv) investigate challenges and opportunities of clean-up technologies for inland waterways (e.g., canals, rivers) and ports. We identified 61 scientific publications on plastic remediation technologies, until June 2022. Thirty-four of these studies were published within the last three years, demonstrating a growing interest. The presented overview indicates that inland waterways are, so far, the preferred field of application, with 22 technologies specifically designed for cleaning up plastics from inland waterways, and 52 additional ones with the potential to be installed in these locations. Given the importance of clean-up technologies in inland waterways, we highlighted their strengths, weaknesses, opportunities, and threats (SWOT). Our results indicate that, despite the challenges, these technologies provide essential prospects, from improving the environmental quality to raising awareness. Our study is instrumental as it illustrates an up-to-date overview and provides a comprehensive analysis of current in design phase, testing, and in use plastic remediation technologies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Increased pressures from human activities may cause cumulative ecological effects on marine ecosystems. Increasingly, the study of ecosystem services is applied in the marine environment to assess the full effects of human activities on the ecosystem and on the benefits it provides. However, in the marine environment, such integrated studies have yet to move from qualitative and score-based to fully quantitative assessments. To bridge this gap, this study proposed a 4-tiered method for summarizing available knowledge and modelling tools to aid in quantitative assessments of ecosystem services supply. First, the ecosystem functioning mechanisms underlying the supply of services are conceptually mapped. Second, the impacts of the human activity of interest are summarized and linked to the first conceptual model in a case-specific model of ecosystem services supply. Third, indicators are selected that would best represent changes in the most important parameters of the conceptual model in a quantitative manner. Fourth, the knowledge gained in the previous steps is used to select models that are most useful to quantify changes in ecosystem services supply under the human pressure of interest. This approach was applied to the case study of offshore wind energy in the Belgian part of the North Sea, which is one of the most rapidly expanding industries in the marine environment globally. This study provides a useful tool to proceed towards quantification of marine ecosystem services, highlighting the need for a fully integrated approach to developing environmental impact assessment tools., Competing Interests: The authors declare no competing interests., (© 2023 The Authors.)

Microplastic is ubiquitously and persistently present in the marine environment, but knowledge of its population-level effects is limited. In the present study, to quantify the potential theoretical population effect of microplastic, a two-step approach was followed. First, the impact of microplastic (polyethylene, 0.995 g cm -3 , diameter 10-45 µm) on the filtration rate of the pelagic copepod Temora longicornis was investigated under laboratory conditions. It was found that the filtration rate decreased at increasing microplastic concentrations and followed a concentration-response relationship but that at microplastic concentrations <100 particles L -1 the filtration rate was not affected. From the concentration-response relationship between the microplastic concentrations and the individual filtration rate a median effect concentration of the individual filtration rate (48 h) of 1956 ± 311 particles L -1 was found. In a second step, the dynamics of a T. longicornis population were simulated for realistic environmental conditions, and the effects of microplastics on the population density equilibrium were assessed. The empirical filtration rate data were incorporated in an individual-based model implementation of the dynamic energy budget theory to deduct potential theoretical population-level effects. The yearly averaged concentration at which the population equilibrium density would decrease by 50% was 593 ± 376 particles L -1 . The theoretical effect concentrations at the population level were 4-fold lower than effect concentrations at the individual level. However, the theoretical effect concentrations at the population level remain 3-5 orders of magnitude higher than ambient microplastic concentrations. Because the present experiment was short-term laboratory-based and the results were only indirectly validated with field data, the in situ implications of microplastic pollution for the dynamics of zooplankton field populations remain to be further investigated. Environ Toxicol Chem 2022;41:1663-1674. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)

Coastal environments are increasingly shown to have a positive effect on our health and well-being. Various mechanisms have been suggested to explain this effect. However, so far little focus has been devoted to emotions that might be relevant in this context, especially for people who are directly or indirectly exposed to the coast on a daily basis. Our preregistered qualitative study explored how coastal residents experience the emotions they feel at the coast and how they interpret the effect these emotions have on them. We conducted semi-structured interviews with a purposive sample of eight Belgian coastal residents aged 21-25 years old. The interviews were analyzed with the approach of interpretative phenomenological analysis. Five superordinate themes were identified and indicate that, for our participants, the coast represents a safe haven (1) in which they can experience emotional restoration (2), awe (3), and nostalgia (4). These emotional states are accompanied with adaptive emotion regulating strategies (5), such as reflection and positive reappraisal, that may facilitate coping with difficult thoughts and feelings. Our study demonstrates the importance of investigating specific emotions and related processes triggered at the coast and how these could contribute to the therapeutic value of the coast., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Severin, Raes, Notebaert, Lambrecht, Everaert and Buysse.)

Microplastics (MPs) were collected at six locations along Kenya's marine nearshore surface waters using a 300 μm mesh-size manta net. The samples were washed over a 125-μm mesh size sieve No.120 into a glass jar and preserved in 70% ethanol. MPs were sorted, counted visually under a dissecting microscope then identified using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. A total of 1473 particles with an overall mean concentration of 0.58 ± 1.29 MPs m -3 , were collected. Fragments were the most common types representing 55% of the total MPs, followed by films (40%) and fibers (2%). Polypropylene (PP) was dominant (52%), high-density polyethylene (HDPE) comprised 38% and low density polyethylene (LDPE) 10% of the total MPs. This study provided baseline information, in which Malindi was identified as a hot spot for MPs pollution. Furthermore, the outcomes will assist policy formulations and management strategies aimed at controlling marine plastics., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Microplastic pollution is an issue of concern due to the accumulation rates in the marine environment combined with the limited knowledge about their abundance, distribution and associated environmental impacts. However, surveying and monitoring microplastics in the environment can be time consuming and costly. The development of cost- and time-effective methods is imperative to overcome some of the current critical bottlenecks in microplastic detection and identification, and to advance microplastics research. Here, an innovative approach for microplastic analysis is presented that combines the advantages of high-throughput screening with those of automation. The proposed approach used Red Green Blue (RGB) data extracted from photos of Nile red-fluorescently stained microplastics (50-1200 μm) to train and validate a 'Plastic Detection Model' (PDM) and a 'Polymer Identification Model' (PIM). These two supervised machine learning models predicted with high accuracy the plastic or natural origin of particles (95.8%), and the polymer types of the microplastics (88.1%). The applicability of the PDM and the PIM was demonstrated by successfully using the models to detect (92.7%) and identify (80%) plastic particles in spiked environmental samples that underwent laboratorial processing. The classification models represent a semi-automated, high-throughput and reproducible method to characterize microplastics in a straightforward, cost- and time-effective yet reliable way., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Current mitigation strategies to offset marine plastic pollution, a global concern, typically rely on preventing floating debris from reaching coastal ecosystems. Specifically, clean-up technologies are designed to collect plastics by removing debris from the aquatic environment such as rivers and estuaries. However, to date, there is little published data on their potential impact on riverine and estuarine organisms and ecosystems. Multiple parameters might play a role in the chances of biota and organic debris being unintentionally caught within a mechanical clean-up system, but their exact contribution to a potential impact is unknown. Here, we identified four clusters of parameters that can potentially determine the bycatch: (i) the environmental conditions in which the clean-up system is deployed, (ii) the traits of the biota the system interacts with, (iii) the traits of plastic items present in the system, and, (iv) the design and operation of the clean-up mechanism itself. To efficiently quantify and assess the influence of each of the clusters on bycatch, we suggest the use of transparent and objective tools. In particular, we discuss the use of Bayesian Belief Networks (BBNs) as a promising probabilistic modelling method for an evidence-based trade-off between removal efficiency and bycatch. We argue that BBN probabilistic models are a valuable tool to assist stakeholders, prior to the deployment of any clean-up technology, in selecting the best-suited mechanism to collect floating plastic debris while managing potential adverse effects on the ecosystem., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Nowadays, a variety of methodologies are available to assess local, regional and global impacts of human activities on ecosystems, which include Life Cycle Assessment (LCA), Environmental Risk Assessment (ERA) and Ecosystem Services Assessment (ESA). However, none can individually assess both the positive and negative impacts of human activities at different geographical scales in a comprehensive manner. In order to overcome the shortcomings of each methodology and develop more holistic assessments, the integration of these methodologies is essential. Several studies have attempted to integrate these methodologies either conceptually or through applied case studies. To understand why, how and to what extent these methodologies have been integrated, a total of 110 relevant publications were reviewed. The analysis of the case studies showed that the integration can occur at different positions along the cause-effect chain and from this, a classification scheme was proposed to characterize the different integration approaches. Three categories of integration are distinguished: post-analysis, integration through the combination of results, and integration through the complementation of a driving method. The literature review highlights that the most recurrent type of integration is the latter. While the integration through the complementation of a driving method is more realistic and accurate compared to the other two categories, its development is more complex and a higher data requirement could be needed. In addition to this, there is always the risk of double-counting for all the approaches. None of the integration approaches can be categorized as a full integration, but this is not necessarily needed to have a comprehensive assessment. The most essential aspect is to select the appropriate components from each methodology that can cover both the environmental and socioeconomic costs and benefits of human activities on the ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

There is a growing interest in replacing fossil-based polymers and composites with more sustainable and renewable fully biobased composite materials in automotive, aerospace and marine applications. There is an effort to develop components with a reduced carbon footprint and environmental impact, and materials based on biocomposites could provide such solutions. Structural components can be subjected to different marine conditions, therefore assessment of their long-term durability according to their marine applications is necessary, highlighting related degradation mechanisms. Through an up-to-date review, this work critically discusses relevant literature on the long-term durability of biocomposites specific for marine environments. Importantly, in this review we report the effects of abiotic parameters, such as the influence of hygrothermal exposures (temperatures and UV radiation) on physical, mechanical and thermal characteristics of biocomposites. Furthermore, we identify and discuss the potential ecotoxicological effects of leaching substances and microplastics derived from biocomposites, as well as the change in mechanical, physical and thermal behaviours correlated to degradation in the fibre matrix interface, surface defects and overall deterioration of the composite's properties. Finally, the combined effects of various environmental exposures on the long-term durability of the biocomposites are critically reviewed., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work presented in this review paper., (This journal is © The Royal Society of Chemistry.)

There is increasing evidence that blue spaces, particularly coastal environments, are beneficial for well-being. During the first-wave lockdown of the COVID-19 pandemic in Belgium, access to the coast was restricted due to restraint in circulation. Making use of this unique opportunity, this study investigated whether access and visits to the coast were positively associated with well-being by using a quasi-experimental design. The emotions of awe and nostalgia were studied as potential mediators between coastal visits and well-being. A total of 687 Flemish adults took part in an online survey that was launched end of April until beginning of June 2020. After controlling for covariates, results showed that access to the coast, but not visit frequency, was positively associated with well-being. More specifically, coastal residents reported less boredom and worry, and more happiness than inland residents. Awe and nostalgia were not significantly associated with coastal visits, but awe was negatively correlated with boredom. The study suggests a potential buffer effect of residential proximity to the coast against negative psychological consequences of the COVID-19 pandemic, supporting the notion that the coast has a positive impact on well-being., Competing Interests: The authors have no competing interests to declare., (Copyright: © 2021 The Author(s).)

The current knowledge about the ecological effects of microplastic (MP) remains limited, and to-date ecotoxicity tests often utilize standard microplastic with one or two distinct size classes and expose the organisms to unrealistically high MP concentrations. We exposed the marine diatom Phaeodactylum tricornutum to microplastic particles of a mimicked realistic size frequency distribution complemented with serial experiments with distinct size classes. To do so, we exposed this diatom to a concentration series of different sized polyethylene (PE) microbeads (sizes: 10-106 µm; 1.25 ×10 2 -1.25 ×10 7 particles/L) in a 72-h growth inhibition test. No effect on the growth of P. tricornutum by virgin PE microbeads up to 1.25 × 10 7 particles/L (or 499 mg/L), indicating environmentally relevant concentrations and sizes of MP does not alter the growth of marine diatoms. Results of smaller sized MPs (10-20 µm) did not differ from those obtained with larger MPs (90-106 µm) and mix sized MPs (10-106 µm), i.e. no impact on the microalgae growth. As a pioneer work, our results contribute with high quality dose-response data to an improved risk assessment of microplastic under realistic present and future marine MP pollution., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Despite the ubiquitous and persistent presence of microplastic (MP) in marine ecosystems, knowledge of its potential harmful ecological effects is low. In this work, we assessed the risk of floating MP (1 μm-5 mm) to marine ecosystems by comparing ambient concentrations in the global ocean with available ecotoxicity data. The integration of twenty-three species-specific effect threshold concentration data in a species sensitivity distribution yielded a median unacceptable level of 1.21 ∗ 10 5  MP m - ³ (95% CI: 7.99 ∗ 10 3 -1.49 ∗ 10 6  MP m - ³). We found that in 2010 for 0.17% of the surface layer (0-5 m) of the global ocean a threatening risk would occur. By 2050 and 2100, this fraction increases to 0.52% and 1.62%, respectively, according to the worst-case predicted future plastic discharge into the ocean. Our results reveal a spatial and multidecadal variability of MP-related risk at the global ocean surface. For example, we have identified the Mediterranean Sea and the Yellow Sea as hotspots of marine microplastic risks already now and even more pronounced in future decades., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Local biodiversity trends over time are likely to be decoupled from global trends, as local processes may compensate or counteract global change. We analyze 161 long-term biological time series (15-91 years) collected across Europe, using a comprehensive dataset comprising ~6,200 marine, freshwater and terrestrial taxa. We test whether (i) local long-term biodiversity trends are consistent among biogeoregions, realms and taxonomic groups, and (ii) changes in biodiversity correlate with regional climate and local conditions. Our results reveal that local trends of abundance, richness and diversity differ among biogeoregions, realms and taxonomic groups, demonstrating that biodiversity changes at local scale are often complex and cannot be easily generalized. However, we find increases in richness and abundance with increasing temperature and naturalness as well as a clear spatial pattern in changes in community composition (i.e. temporal taxonomic turnover) in most biogeoregions of Northern and Eastern Europe.

The health risks of coastal areas have long been researched, but the potential benefits for health are only recently being explored. The present study compared the general health of Belgian citizens a) according to the EU's definition of coastal (<50 km) vs. inland (>50 km), and b) between eight more refined categories of residential proximity to the coast (<5 km to >250 km). Data was drawn from the Belgian Health Interview Survey (n = 60,939) and investigated using linear regression models and mediation analyses on several hypothesized mechanisms. Results indicated that populations living <5 km of the coast reported better general health than populations living at >50-100 km. Four commonly hypothesized mechanisms were considered but no indirect associations were found: scores for mental health, physical activity levels and social contacts were not higher at 0-5 km from the coast, and air pollution (PM 10 concentrations) was lower at 0-5 km from the coast but not statistically associated with better health. Results are controlled for typical variables such as age, sex, income, neighbourhood levels of green and freshwater blue space, etc. The spatial urban-rural-nature mosaic at the Belgian coast and alternative explanations are discussed. The positive associations between the ocean and human health observed in this study encourage policy makers to manage coastal areas sustainably to maintain associated public health benefits into the future., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The Belgian part of the North Sea (BPNS) is subjected to multiple environmental stressors. The impact of these stressors includes the modulation of fatty acid (FA) composition of the zooplankton. This study recorded temporal and spatial patterns of the FA profiles of two dominant calanoid copepods within the BPNS: Temora longicornis (Müller, 1785) and Acartia clausi (Giesbrecht, 1889). By means of distance-based linear modelling and by applying multi model inference to generalized additive models, environmental stressors were linked to patterns of the FA profiles of these species. The FA profiles of A. clausi and T. longicornis showed distinct intraspecific, spatial and temporal differences within the BPNS. Temperature and algal food quality (marked by the ratio of silicate concentration to dissolved inorganic nitrogen concentration, SiO 4 /DIN) were the most important drivers of seasonal fluctuations in the DHA/EPA ratio of both species. DHA/EPA ratio can be used as marker for stress in copepods in the BPNS in order to have a quick indication of food quality changes at the basis of the food web., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

We performed an environmental risk assessment for microplastics (<5 mm) in the marine environment by estimating the order of magnitude of the past, present and future concentrations based on global plastic production data. In 2100, from 9.6 to 48.8 particles m -3 are predicted to float around in the ocean, which is a 50-fold increase compared to the present-day concentrations. From a meta-analysis with effect data available in literature, we derived a safe concentration of 6650 buoyant particles m -3 below which adverse effects are not likely to occur. Our risk assessment (excluding the potential role of microplastics as chemical vectors) suggests that on average, no direct effects of free-floating microplastics in the marine environment are to be expected up to the year 2100. Yet, even today, the safe concentration can be exceeded in sites that are heavily polluted with buoyant microplastics. In the marine benthic compartment between 32 and 144 particles kg -1 dry sediment are predicted to be present in the beach deposition zone. Despite the scarcity of effect data, we expect adverse ecological effects along the coast as of the second half of the 21st century. From then ambient concentrations will start to outrange the safe concentration of sedimented microplastics (i.e. 540 particles kg -1 sediment). Additional ecotoxicological research in which marine species are chronically exposed to realistic environmental microplastic concentration series are urgently needed to verify our findings., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Ecological risk assessment is commonly based on single-generation ecotoxicological tests that are usually performed at one standard temperature. We investigated the effects of nickel (Ni) on Daphnia magna reproduction at 15, 20, and 25 °C over 4 generations. Multigenerational Ni effects on D. magna reproduction depended on the magnitude of the effect in the first generation (F0) and showed very different patterns at different temperatures. At low effect level concentrations (<10% effect concentration [EC10] in F0), chronic Ni toxicity at 15 and 20 °C did not increase over 4 generations, and the increase in Ni toxicity at 25 °C observed in F1 and F2 in some Ni treatments did not persist into F3, where complete recovery of reproduction was observed. At higher effect level concentrations, the multigenerational Ni effects depended on the test temperature. In F0, Ni toxicity was 6.5-fold lower at 25 °C than at 15 °C (based on the median effect concentration), but the temperature effect on Ni toxicity was not explained by differences in Ni accumulation. At a lower temperature, lower internal Ni concentrations in D. magna were necessary to induce the same Ni toxicity as at a higher temperature. Overall, our results indicate that low single-generation chronic effect concentrations of Ni in D. magna (EC10 in the present study) are also protective in a long-term, multigenerational context and that temperature should be taken into account in the ecological risk assessment of Ni. Environ Toxicol Chem 2018;37:1877-1888 © 2018 SETAC., (© 2018 SETAC.)

The effect of multiple stressors on marine ecosystems is poorly understood. To partially bridge this knowledge gap we investigated the relative contribution of environmental variables to density and diversity dynamics of the zooplankton community in the Belgian part of the North Sea. We applied multimodel inference on generalized additive models to quantify the relative contribution of chlorophyll a, temperature, nutrients, salinity and anthropogenic chemicals (i.e. polychlorinated biphenyls and polycyclic aromatic hydrocarbons) to the dynamics of calanoid copepod species in the Belgian part of the North Sea. Temperature was the only predictor consistently showing a high importance in all models predicting the abundances of the selected copepod species. The relative contribution of other predictors was species-dependent. Anthropogenic chemicals were important predictors for three out of six species indicating that chemical mixtures at low concentrations should not be left unattended when performing risk assessments in a natural environment., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

We characterized spatial patterns of surface sediment concentrations of seven polychlorinated biphenyls (PCBs), seven polycyclic aromatic hydrocarbons (PAHs), three chlorinated pesticides, and five metals in Norwegian waters and Skagerrak. In total, we analyzed 5036 concentrations of 22 chemical substances that were measured between 1986 and 2014 at 333 sampling sites by means of generalized additive models (GAMs). We found that GAMs with organic carbon content of the sediment and latitude and longitude as co-variates explained as ca. 75% of the variability of the contaminant sediment concentrations. For metals, a predominantly hotspot-driven spatial pattern was found, i.e., we identified historical pollution hotspots (e.g., Sørfjord in western Norway) for mercury, zinc, cadmium, and lead. Highest concentrations of PAHs and PCBs were found close to densely populated and industrialized regions, i.e., in the North Sea and in the Kattegat and Skagerrak. The spatial pattern of the PCBs suggests the secondary and diffuse atmospheric nature of their sources. Atmospheric inputs are the main sources of pollution for most organic chemicals considered, but north of the Arctic circle, we found that concentrations of PAHs increased from south to north most likely related to a combination of coal-eroding bedrock and the biological pump. The knowledge acquired in the present research is essential for developing effective remediation strategies that are consistent with international conventions on pollution control.

In this paper we determine whether a realistic mixture of hydrophobic chemicals affects the growth dynamics of a marine diatom and how this effect compares to the effect of temperature, light regime and nutrient conditions. To do so, we examine the specific growth rate of Phaeodactylum tricornutum in a 72 h algal growth inhibition test using a full factorial design with three nutrient regimes, two test temperatures, three light intensities and three chemical exposures. Passive samplers were used to achieve exposure to realistic mixtures of organic chemicals close to ambient concentrations. Nutrient regime, temperature and time interval (24, 48 and 72 h) explained 85% of the observed variability in the experimental data. The variability explained by chemical exposure was about 1%. Overall, ambient concentrations of hydrophobic compounds present in Belgian coastal waters, and for which the passive samplers have affinity, are too low to affect the intrinsic growth rate of P. tricornutum., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In this paper, we use concentrations of persistent organic pollutants (POPs) and of chlorophyll a to infer POP-induced effects on marine primary production in the Kattegat and the North Sea between the 1990s and the 2000s. To do so, we modelled phytoplankton dynamics using four classical drivers (light and nutrient availability, temperature and zooplankton grazing) and tested whether extending this model with a POP-induced phytoplankton growth limitation term improved model fit to observed chlorophyll a concentrations. Including monitored concentrations of PCBs and pesticides did not lead to a better model fit, suggesting that POP-induced growth limitation of marine phytoplankton in the North Sea and the Kattegat is small compared to the limitations caused by the classical drivers. In an attempt to more fully represent the multitude of POPs in the marine environment, the monitored concentrations were multiplied with a factor 10 and 100. Under these two configurations, region-specific contributions of POPs in the phytoplankton growth limitation were found. The inferred contribution of POPs to phytoplankton growth limitation was ca. 1% in Belgian marine waters, but in the Kattegat POPs explained ca. 10% of the phytoplankton growth limitation. These results suggest that there are regional differences in the contribution of POPs to the phytoplankton growth limitation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We analyzed three decades of field observations in the North Sea with additive models to infer spatiotemporal trends of chlorophyll a concentration, sediment organic carbon content, and polychlorinated biphenyls (PCBs) concentrations in mussels and sediments. By doing so, we separated long-term changes in PCB concentrations from seasonal variability. Using the inferred seasonal variability, we demonstrated that phytoplankton blooms in spring and autumn correspond to the annual maxima of the organic carbon content (r = 0.56; p = 0.004) and the PCB concentrations in sediments (r = 0.57; p = 0.004). Furthermore, we found a negative correlation between the PCB concentrations in sediments and in blue mussels (Mytilus edulis; r = -0.33, p = 0.012), which is probably related to the cleansing of the dissolved PCB phase driven by sinking organic matter during phytoplankton blooms and the filter-feeding behavior of the blue mussel. The present research demonstrates the role of seasonal phytoplankton dynamics in the environmental fate of PCBs at large spatiotemporal scales.

Blackflies are important macroinvertebrate groups from a public health as well as ecological point of view. Determining the biological and environmental factors favouring or inhibiting the existence of blackflies could facilitate biomonitoring of rivers as well as control of disease vectors. The combined use of different predictive modelling techniques is known to improve identification of presence/absence and abundance of taxa in a given habitat. This approach enables better identification of the suitable habitat conditions or environmental constraints of a given taxon. Simuliidae larvae are important biological indicators as they are abundant in tropical aquatic ecosystems. Some of the blackfly groups are also important disease vectors in poor tropical countries. Our investigations aim to establish a combination of models able to identify the environmental factors and macroinvertebrate organisms that are favourable or inhibiting blackfly larvae existence in aquatic ecosystems. The models developed using macroinvertebrate predictors showed better performance than those based on environmental predictors. The identified environmental and macroinvertebrate parameters can be used to determine the distribution of blackflies, which in turn can help control river blindness in endemic tropical places. Through a combination of modelling techniques, a reliable method has been developed that explains environmental and biological relationships with the target organism, and, thus, can serve as a decision support tool for ecological management strategies.

We assessed and compared abiotic preferences of aquatic macroinvertebrates in three river basins located in Ecuador, Ethiopia and Vietnam. Upon using logistic regression models we analyzed the relationship between the probability of occurrence of five macroinvertebrate families, ranging from pollution tolerant to pollution sensitive, (Chironomidae, Baetidae, Hydroptilidae, Libellulidae and Leptophlebiidae) and physical-chemical water quality conditions. Within the investigated physical-chemical ranges, nine out of twenty-five interaction effects were significant. Our analyses suggested river basin dependent associations between the macroinvertebrate families and the corresponding physical-chemical conditions. It was found that pollution tolerant families showed no clear abiotic preference and occurred at most sampling locations, i.e. Chironomidae were present in 91%, 84% and 93% of the samples taken in Ecuador, Ethiopia and Vietnam. Pollution sensitive families were strongly associated with dissolved oxygen and stream velocity, e.g. Leptophlebiidae were only present in 48%, 2% and 18% of the samples in Ecuador, Ethiopia and Vietnam. Despite some limitations in the study design, we concluded that associations between macroinvertebrates and abiotic conditions can be river basin-specific and hence are not automatically transferable across river basins in the tropics.

We developed generalised additive mixed models (GAMMs) to infer spatiotemporal trends of environmental PCB concentrations from an extensive dataset (n=1219) of PCB concentrations measured between 1991 and 2010 in sediments of the Belgian Coastal Zone (BCZ) and the Western Scheldt estuary. A GAMM with time, geographical zone, periodicity and the organic carbon - water partition coefficient as covariates explained 49% of the variability in the log transformed PCB sediment concentrations. The time trends unraveled two to threefold PCB concentration decreases in the BCZ during the last 20 years. However, in the Western Scheldt estuary, time trends were spatially heterogeneous and not significantly decreasing. These results demonstrate that international efforts to cut down emissions of PCBs have been effective to reduce concentrations in open water ecosystems like the BCZ but had little effect in the urbanised and industrialised area of the Scheldt estuary., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Worldwide, large investments in wastewater treatment are made to improve water quality. However, the impacts of these investments on river water quality are often not quantified. To assess water quality, the European Water Framework Directive (WFD) requires an integrated approach. The aim of this study was to develop an integrated ecological modelling framework for the River Drava (Croatia) that includes physical-chemical and hydromorphological characteristics as well as the ecological river water quality status. The developed submodels and the integrated model showed accurate predictions when comparing the modelled results to the observations. Dissolved oxygen and nitrogen concentrations (ammonium and organic nitrogen) were the most important variables in determining the ecological water quality (EWQ). The result of three potential investment scenarios of the wastewater treatment infrastructure in the city of Varaždin on the EWQ of the River Drava was assessed. From this scenario-based analysis, it was concluded that upgrading the existing wastewater treatment plant with nitrogen and phosphorus removal will be insufficient to reach a good EWQ. Therefore, other point and diffuse pollution sources in the area should also be monitored and remediated to meet the European WFD standards.

The formation of weak molecular complexes of cyclopentene with HCl and BF3, dissolved in liquid argon is investigated using infrared spectroscopy. Evidence is found for the formation of 1:1 complexes in which the Lewis acid under study binds to the CC double bond. At higher concentrations of HCl, weak absorption bands due to 1:2 species are also observed. From spectra recorded at different temperatures between 92 and 127 K, the complexation enthalpies for CP.HCl and CP.BF3 are determined to be -9.5(3) and -16.1(9) kJ mol-1, while for CP.(HCl)2 a value of -17.0(6) kJ mol-1 is obtained. For the 1:1 and 1:2 complexes, structural and spectral information is obtained from ab initio calculations at the MP2/6-31+G(d) level. Using free energy perturbation Monte Carlo simulations to calculate the solvation enthalpies and statistical thermodynamics to account for zero-point vibrational and thermal contributions, the complexation energies for CP.HCl and CP.(HCl)2 are estimated from the experimental complexation enthalpies to be -17.4(14) and -34.0(20) kJ mol-1, while the value for CP.BF3 was derived to be -23.4(22) kJ mol-1. The experimental complexation energies are compared with the theoretical values derived from the MP2/6-31+G(d) potential energy surfaces and with single point energies calculated at the MP2/6-311++G(3df,2pd) level.

The possibility of acyl migrations in ester saponins from Maesa lanceolata was investigated by molecular mechanics and electronic structure calculations carried out on the major constituent maesasaponin IV3 (3beta-O-[[alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-galactopyranosyl-(1-->3)]-[beta-D-galactopyranosyl-(1-->2)]-beta-D-gluco-pyranuronyl]-21beta-angeloyloxy-22alpha-propanoyloxy-13beta,28-oxido-olean-16alpha, 28alpha-diol). It was confirmed that acyl migrations could occur in rings D and E of maesasaponins.