Comparison of the macro-, meso- and microplastic pollution in French riverbanks and beaches using citizen science with schoolchildren

Comparison of the macro-, meso- and microplastic pollution in French riverbanks and beaches using citizen science with schoolchildren | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparison of the macro-, meso- and microplastic pollution in French riverbanks and beaches using citizen science with schoolchildren Léna Philip, Maela Le Picard, Edouard Lavergne, Pascaline Bourgain, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3870685/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 13 Nov, 2024 Read the published version in Environmental Science and Pollution Research → Version 1 posted 5 You are reading this latest preprint version Abstract Rivers are the major source of anthropogenic litters entering the ocean, especially plastic debris that accumulate in all ecosystems around the world and pose a risk to the biota. Reliable data on distribution, abundance and types of stranded plastics are needed, especially on riverbanks that have received less attention than beaches. Here, we present the citizen science initiative Plastique à la loupe (Plastic under the magnifier), that compares for the first time the distribution of different litter sizes (macrolitters, meso- and microplastics) over 81 riverbanks and 66 beaches sampled in France between 2019 and 2021. A total of 149 classes (3,113 schoolchildren) from middle class to high school collected, sorted and enumerated 55,986 pieces of plastic to provide a baseline of the current pollution by stranded debris at the national level. Single-use plastics (mainly food-related items) were very abundant on riverbanks (43%), whereas fragmented debris dominated the macrolitter on beaches (28%). Microplastics were always higher in number compared to mesoplastics and macrolitter, with polystyrene and polyethylene found in equivalent proportions on riverbanks while polyethylene dominated microplastics on beaches. Tracing the source of plastic items was possible only for a small proportion of the numerous collected items, mainly for identifiable macrolitter and microplastic pellets. This study lays out the foundations for further works using Plastique à la loupe citizen science initiative in France and additional comparisons to other studied habitats worldwide, which can be used by scientists and policy-makers for future litter monitoring, prevention and clean-up strategies. Citizen science plastic pollution riverbanks beaches Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Plastic pollution has been documented in all major ocean basins and a growing number of freshwater and terrestrial environments (Bucci et al., 2020). Despite a growing literature in the last decade, the ultimate fate of plastic debris and its transport mechanisms in terrestrial, freshwater, and marine environments are poorly understood, at both regional and global levels (Zhu, 2021). There is a peculiar, several orders of magnitude mismatch between projected litter emissions into the ocean (Jambeck et al., 2015) and global estimates based on field data (Van Sebille et al., 2015), indicating hitherto insufficiently accounted sinks such as remote beaches and riverbanks (Bergmann et al., 2017). The importance of tackling plastic litter worldwide has been globally recognized in the context of the 2030 agenda for sustainable development, adopted by all United Nations Member States in 2015 (see target 14.1 in United Nations, 2015). In the marine environment, plastic litter is one of the 11 descriptors of Good Environmental Status (GES) of the European Marine Strategy Framework Directive (2008/56/EC, MSFD) (Galgani et al., 2013). In freshwater, contamination by plastic litters has not yet been considered as a descriptor of good environmental status, including for example the European Water Framework Directive (2000/60/EC, WFD). This gap could be explained by the lack of data relating the occurrence and associated effects of plastic contamination in freshwater ecosystems (Dris et al., 2015). Several studies recognized that plastics with terrestrial usages are the main sources of marine plastic pollution, either by direct emission from coastal zones (Li et al., 2021) or transport through rivers (Lebreton et al., 2017; Schmidt et al., 2017; Weig et al., 2021). Riverine plastic transport remains understudied and the better understanding of the sources and pathways of plastics in freshwater ecosystems is a prerequisite to develop effective prevention and collection strategies. Gathering sufficient data for scientific research is challenging, with limited sampling time and human resources involved in classical scientific projects (Zettler et al., 2017). Because marine litters are easily identifiable and their quantification requires relatively little scientific training, it is particularly well suited for engaging citizen scientists to expand our knowledge of the spatial and temporal distribution of marine litter, especially in remote, under-sampled areas (Hidalgo-Ruz & Thiel, 2015). In addition to data provisioning, citizen engagement serves as an outreach mechanism to inform and involve the general public on scientific progress (Silvertown et al., 2013). An increasing number of citizen science initiatives exist on plastic litter, mainly focusing on macro- and microplastics washed or deposited on beaches or shorelines (beach litter) in the United States (Barrows et al., 2018; Uhrin et al., 2020), China (Chen et al., 2020), Indonesia (Syakti et al., 2017), United Kingdom (Nelms et al., 2020), Danemark (Syberg et al., 2020), British Columbia and Canada (Harris et al., 2021), Chili (Bravo et al., 2009), Australia (Carbery et al., 2020; van der Velde et al., 2017), Svalbard (Bergmann et al., 2017), and Lofoten Island (Haarr et al., 2020). Other initiatives with focus on floating plastic debris were carried out in the United States (Davis & Murphy, 2015), Sweden (Gewert et al., 2015) and Taiwan (Chiu et al., 2020). Studies on plastic debris on the seafloor were conducted in the United Kingdom (Nel et al., 2020) and across 13 countries in Europe (Lots et al., 2017). Surprisingly, none of these initiatives considered riverbanks despite the need of data on plastic quantification at the source of the pollution. Plastic debris encompass a wide size distribution, from large abandoned and derelict consumer litters (often single-use products) to unrecognizable fragments of meso- (from 25 mm to 5 mm) and microplastics (5 mm to 500 µm) (Hinata et al., 2017). Several methodologies for monitoring marine litter already exist. Among them, the OSPAR beach litter protocol is one of the most used to monitor macrolitter on beaches (OSPAR, 2020) and it has been adapted to monitor macrolitter on riverbanks (Van Emmerik & Schwarz, 2020). This study presents the first citizen science initiative dedicated to the comparison between macro-, meso- and microplastic debris on riverbanks and beaches. Plastique à la loupe is also the first initiative conducted in France, engaging 3,113 teenagers and their teachers from 149 schools across the nation collecting and extracting samples since 2019. Here, we focused on assessing the composition, distribution and abundance of plastic debris on riverbanks and beach surveys in France from data collected between 2019 and 2021 (Fig. 1 ). Schoolchildren have used the same scientific protocol as developed during the Tara Microplastic expedition, adapted from the OSPAR protocol (Ghiglione et al., 2023). We ended up with 43,571 macro- and mesoplastic items that were characterized together with 12,415 microplastics for analysis by Fourier transform infrared spectroscopy (FTIR). This study confirms the potential of using citizen science for relevant analysis of macro-, meso- and microplastic pollution on riverbanks and beaches. Materials and methods Study sites Study sites were first chosen by teachers based on local experience and further validated by the scientific committee. Selection criteria were defined from OSPAR and MSFD recommendations and adapted to the citizen science format in order to guarantee the safety of participants and the quality of the data collected (OSPAR, 2020; MSFD TG ML, 2013), including: (1) absence of danger, (2) easy access, (3) presence of deposited litter, (4) absence of cleaning in the 15 days before the sampling, (5) minimum length of 10 m for riverbanks and 50 m for beaches, (6) presence of sand for microplastic sampling. A total of 81 riverbanks and 66 beaches were visited by 149 classes from middle to high school (11 to 18 years old). Sampling sites were spread over the whole French metropolitan territory, in 17 of the 30 academies of the French Ministry of National Education (Fig. 1 ). The classes sampled in the field between September and March 2019–2020 and 2020–2021. Each class was asked to fill a site description form (adapted from the OSPAR beach litter monitoring form; OSPAR, 2010). Information collected includes orientation of the site, sand granulometry, uses (seasonal/annual), accessibility and nature of the site's surroundings (town, village, port, estuary, landfill sites, sewage treatment plant, etc.) as well as the frequency and method of cleaning (if relevant) (Supplementary data 1). Stranded macrolitters Stranded macrolitters were surveyed using a method adapted from the OSPAR methodology (OSPAR 2020), with a slight difference depending on whether sites presented wrack lines. On a section with a known length ranging from 10 to 100 m and located from the first wrack line near the river or coast to the back of the riverbank or beach, classes collected all visible litters larger than 2.5 cm (Fig. 2 A). In the absence of a visible wrack line, sampling was made on the whole width of the riverbank or beach across the section (Fig. 2 B). The collected litter was placed in bin bags, except for items that were too large or too heavy, which were left on site and noted for later counting. Collected litter was brought back to the classroom, for estimation of the volume (L) and measurement of the mass (kg) of total macrolitter. Each litter was sorted, identified and counted according to the OSPAR beach litter survey data form, enriched with additional litter types such as Covid19 crisis related items (disposable mask…) and reorganized by item uses categories (fishing related, medical…) to assist the macrolitter identification. Some items including single used plastic items (straws, lolly sticks,…) and foamed polystyrene fragments were separated for a better focus. The survey data form describing the different categories, types and uses, is presented in supplementary data (Supplementary data 2). A picture was taken once all litters were sorted, and litters were then disposed according to their composition in the appropriate waste disposal center. Results obtained were expressed in volume, mass and number for 100 linear meters of riverbank or beach, 100 meters being the survey unit adopted for OSPAR and MSFD assessments of beach litter (OSPAR, 2020, MSFD TG ML, 2023). The calculation was performed by dividing the data obtained by the number of linear meters surveyed and multiplying by 100. Data normalization was done relative to 100 linear meters rather than surfaces in order to avoid the bias induced by tides, which changes the surface of the sampling area depending on the time of the sampling and therefore, the density of items on the beach. Stranded meso- and large microplastics Stranded mesoplastics and large microplastics were assessed using a method proposed at the European level to monitor mesolitter fragments and pellets on the coastline (MSFD TG ML, 2023). The protocol consists in delimiting three 50 cm-wide bands evenly distributed over the macrolitter section, and sampling along these three bands, perpendicularly to the water line, either on each wrack line (Fig. 2 A) or on the whole riverbank or beach width in the absence of visible wrack lines (Fig. 2 B). Materials used for sampling were made of metal or glass to prevent any sample contamination. Samplings were done by collecting sand surface using a trowel on the three bands. To limit organic matter and sand collection, meso- and microplastics were extracted directly on site, by flotation in either seawater (for coastal sites) or freshwater (for river sites). Floating particles were recovered with a metallic cooking sieve with a mesh size of 1 mm, then stored in a metal tray and brought back to class for sorting. Once in classroom, samples from the three subsamples were treated separately, by visually sorting organic debris and plastics. Plastics were then sorted according to their size class: mesoplastics [0.5; 2.5 cm] and large microplastics [0.1; 0.5 cm]. The particles were then counted according to their type (fibers, pellets, fragments...) and color based on a list adapted from MSFD microlitter monitoring guidelines (MSFD TG ML, 2023) as presented in the survey data form (Supplementary data 2). Meso- and microplastic lists were the same except for the industrial plastic pellets (IPP) category (also known as nurdle or pellet), which is only included in the microplastic list. Results were expressed in number of particles by 100 linear meters of riverbank or beach, by dividing the number of particles by 1.5 m (corresponding to 3x50 cm-wide bands) and multiplying by 100 m. After sorting, a picture of each sample was taken. 96 microplastics were then selected randomly in the sample and sent to the Observatoire Océanologique de Banyuls sur mer (OOB, France) or to the Cedre (Brest, France), for polymer composition analysis by Fourier transformed infrared spectroscopy (FTIR). FTIR analyses were performed with following parameters: 32 scans, 4 of resolution and large scale from 4000 to 600 cm − 1 . Polymer identification was performed using the POSEIDON tool that contains a spectra bank obtained from microplastics collected during the Tara Mediterranean (2014) and Tara Microplastic (2019) expeditions (Ghiglione et al., 2023; Kedzierski et al., 2019). Data management and analysis Survey data forms were gathered for riverbanks and beaches, and raw data were normalized for 100 linear meters. Some sites were excluded from the analysis when the length of the sampling section was not mentioned by schools. Data from riverbanks and beaches were treated separately. For Figs. 3 C, 4 , 5 and 6 , proportions were calculated from normalized data for each site, and the mean of theses proportions was calculated to have information on the dispersion of data. For plastic litter size analysis (Fig. 6 ), only the sites with complete sampling of macro-, meso-, and microplastics on a known section were studied. Correlations between numbers of macro-, meso-, and microplastics were calculated for riverbanks and beaches separately. Data normality was tested using a Shapiro test. Correlation indexes were calculated using the non-parametric Spearman test. Results Number, mass and composition of macrolitters on riverbanks and beaches A total of 81 riverbanks from large and small rivers were sampled in France, together with 66 beaches located along the French coastline either on the coast of the Mediterranean Sea, the Atlantic Ocean or the English Channel). Among all the sites that were studied, only two were not polluted with macrolitter on the sampling zone; however, for one of these two sites, the area surrounding the sampling section was highly polluted, mainly with glass debris. The median number of macrolitters per 100 linear meters collected on riverbanks was approximatively twice lower (median = 232 for 100 linear meters, n = 81) than on beaches (median = 443 for 100 linear meters, n = 66) (Fig. 3 A). Mean numbers of macrolitter per 100 linear meters were much higher than median numbers, on both riverbanks and beaches, due to extreme sites (1032 ± 2147 macrolitter for 100 linear meters and 1276 ± 2623 respectively). The opposite tendency was observed when expressing macrolitters by weight, in kg of litter per 100 linear meters (median = 10.0 kg, n = 67 sites and median = 5.1 kg, n = 52 sites per 100 linear meters on riverbanks and beaches, respectively) (Fig. 3 B). Plastic was the most dominant debris type in number of items compared to the total number of collected litters, with a lower proportion on riverbanks than on beaches (55.1 ± 30.4 and 80.0 ± 22.4% respectively). Other debris were composed of glass (16.3 ± 20.8 and 8.4 ± 17.8% respectively), metals (13.0 ± 15.3 and 2.7 ± 4.5% respectively), paper and cardboard (5.3 ± 9.1 and 1.2 ± 2.2% respectively), ceramics (2.7 ± 7.9% and 1.4 ± 3.9% respectively), textiles (2.7 ± 5.0% and 1.1 ± 2.6% respectively), wood (1.5 ± 4.5% and 3.0 ± 6.7% respectively) and rubber (0.9 ± 2.7 and 2.2 ± 4.0% respectively) (Fig. 3 C). Common macroplastic types and composition on riverbanks and beaches Macroplastic debris found across all riverbanks (n = 81 sites) were dominated by single-use disposable plastics (43.4 ± 26.2%), whereas it represented only 27.6 ± 17.4% on beaches (n = 66 sites) (Fig. 4 A and 4 C). Plastic fragments were the second dominant plastic type collected on riverbanks (23.2 ± 24.8%), despite it dominated the plastic debris on beaches (28.7 ± 24.5%). Marine activities-related items (fishing, aquaculture and maritime gears) were more present on beaches (24.9 ± 21.7%) than on riverbanks (4.5 ± 9.8%). Inversely, bags and wrappers were more abundant on riverbanks (11.5 ± 16.5%) compared to beaches (5.3 ± 7.9%). The same trend was found for sanitary and medical items (3.0 ± 10.1% and 2.7 ± 12.0% respectively on riverbanks and < 0.6% on beaches). A significant number of unclassified items (recognizable items that were not listed in the survey data form) were found on both riverbanks (10.5 ± 16.9%) and beaches (10.8 ± 17.9%) (Fig. 4 A and 4 B), limiting the description of macrolitters on the studied sites. Focus on single-use disposable plastics on riverbanks and beaches Single-use disposable plastics represented 43.3 ± 26.2% and 27.6 ± 17.4% of all macrolitter on riverbanks and beaches respectively. They were dominated by thin wrappers and caps on both riverbanks (20.5 ± 28.1% and 15.7 ± 23.1%, respectively) and beaches (18.7 ± 19.8% and 24.1 ± 23.2%, respectively) (Fig. 4 C and 4 D). Drink containers, shopping bags and food containers were found in higher proportions on riverbanks (12.3 ± 18.8%, 8.2 ± 19.3% and 4.5 ± 9.5 respectively), despite they were also present on beaches (6.4 ± 15.3%, 3.9 ± 10.9% and 1.2 ± 3.9%, respectively). Inversely, cigarette butts, lollipop sticks and cotton swabs were found in higher proportions on beaches (17.2 ± 21.6%, 11.2 ± 13.0% and 6.5 ± 15.2%, respectively) compared to riverbanks (12.6 ± 24.0%, 5.8 ± 16.8 and 1.1 ± 4.7%, respectively) (Fig. 4 C and 4 D). Comparison between macro-, meso- and microplastics on riverbanks and beaches Microplastics represented a major part of the number of plastics found on both riverbanks (47.0 ± 34.2%, n = 67 sites) and beaches (45.7 ± 25.5%, n = 51 sites) (Fig. 5 ). It is noteworthy that the industrial plastic pellets (IPP) itself represented around a quarter of the microplastics found on riverbanks and beaches (22.5 ± 28.1% and 25.2 ± 28.1% of sampled microplastics respectively, corresponding to 13.1 ± 22.4% and 13.3 ± 19.5% of total plastics, respectively), while the rest of microplastics was mostly dominated by fragmented pieces. The second most dominant plastics on riverbanks were fragmented mesoplastics (21.7 ± 25.9% and 35.9 ± 22.0% of total plastics on riverbanks and beaches, respectively). On beaches, macroplastics were found in lowest proportion (16.8 ± 24.7%), whereas it represented 31.3 ± 31.4% of total plastics on riverbanks. Here, it is noticeable that a large proportion of macroplastics found on beaches were too fragmented to be identified (representing 6.6 ± 13.6% of total plastics) (Fig. 5 ), whereas the other part were recognizable macroplastics as depicted in Fig. 4 A and Fig. 4 B. Chemical composition of microplastics on riverbanks and beaches Similar polymer types were found for microplastics collected both on riverbanks (n = 49 sites) and on beaches (n = 39 sites), but with a clear difference in their relative proportions (Fig. 6 ). On riverbanks, most of the microplastics were made of polystyrene (PS) and polyethylene (PE) (30.7 ± 36.8% and 30.6 ± 27.7 respectively) whereas beaches were clearly dominated by PE (52.1 ± 26.2%). On beaches, PS and polypropylene (PP) were found in similar proportions (16.3 ± 23.8% and 16.1 ± 17.5% respectively). Among microplastics studied on riverbanks, only 6.4 ± 12.7% were made of PP. Ethylene-vinyl acetate (EVA) represented only 1.6 ± 5.2% and 0.8 ± 2.4% on riverbanks and beaches respectively. It is noteworthy that a non-negligeable proportion of sampled micro-particles were natural ones, certainly mistaken for plastics when sorted out, representing the sampling error for microplastics (16.5 ± 21.6% and 4.3 ± 8.1% on riverbanks and beaches respectively). A proportion of microplastics was not identified (7.9 ± 13.6% and 7.1 ± 13.7% on riverbanks and beaches respectively) (Fig. 6 ). Discussion Adding riverbanks to beaches citizen science monitoring for macrolitter, meso- and microplastics Monitoring efforts for stranded debris have mostly focused on beaches (Serra-Gonçalves et al., 2019). Riverbanks are constantly supplied with plastic debris from the rivers, driving the need for more research and management of marine debris. Riverbanks were poorly investigated, with generally very few numbers of studied sites per river (Bruge et al., 2018; Rech et al., 2015). Only one study involved a large number of sites in German rivers, by involving citizen science with schoolchildren (Kiessling et al., 2019). Citizen science monitoring provides a baseline understanding of debris composition, concentration and sources, and helps inform policies to reduce environmental impacts of plastic debris (Nelms et al., 2022). Numerous initiatives exist all around the world (Kawabe et al., 2022), but this study provides the first citizen science initiative for a comparison between debris found on riverbanks and beaches. This baseline study presents the application of debris citizen science monitoring called “ Plastique à la loupe ” to establish the first large-scale and long-term debris dataset for France, making it accessible to facilitate cost effective research efforts. In this study, conscientious collection by 3,113 schoolchildren from 149 classes removed a total of 48,023 macrolitters on riverbanks (n = 81 sites) and beaches (n = 66 sites) in two years. This labor-intensive monitoring effort would not have been feasible by a group of scientists, thus underlying the power of the Plastique à la loupe citizen science initiative for a French national survey. Since 2022, this dataset is used as complementary data in national assessments of aquatic litter pollution conducted by Cedre for French authorities in the context of the MSFD or other international monitoring programs. Data quality controls Participants were provided with support documents and visioconferences twice a year (by groups of 10 to 20 classes), allowing to gain confidence in their data-collection skills which was critical. The support document tool kit for teachers included (i) a support guide to explain the general concepts and objectives of the Plastique à la loupe initiative together with answer to frequently asked questions (FAQ), (ii) an easy and straightforward protocol guide slightly adapted from the OSPAR beach litter monitoring form (OSPAR, 2010), (iii) a photoguide for the macrolitter identification and (iv) a video guide for in situ training. The reliability of the sampling area chosen by the teachers was also verified by the scientists for each class. In addition, at the beginning of the schoolyear, the teams of teachers involved benefited from a one day formation to the project in the presence of the educational team of the Tara Ocean Foundation. A main concern regarding citizen-science studies is whether the collected data are reliable and comparable to professional studies. In order to test the reliability of the sampling, sorting and data acquisition, 8 sampling sites (6 on riverbanks and 2 on beaches) were first analyzed by scientists (without removing plastics) before the on-site visit of schoolchildren and comparison showed no or very little difference for mesoplastics and macrolitter (data not shown). No significant difference with results gathered by experienced scientists was found in other citizen science studies performing similar data quality control (Thiel et al., 2013). However, more errors were found by the schoolchildren for the microplastics with non-plastic particles representing around 7% of the total number of microplastics on riverbanks and beaches. As previously observed, it was found that glass shards for example had been misidentified as small plastic debris (Hidalgo-Ruz & Thiel, 2015). This error can be easily corrected by the FTIR analysis that helps to detect non-plastic particles, which mitigates the impact of such error on the results. Once the sampling site validation step was performed by scientists, only one site was excluded from the analysis for the length of the section was missing, thus underlying the high levels of coordination and personal motivation. Here, we underlined the importance of several steps including encouraging schoolchildren and teachers to describe any uncertainties to researchers, data auto-evaluation and communication of results as a concluding activity to enhance their commitment to the activity. Distribution and composition of all debris on riverbanks and beaches We observed that around 55% of all debris collected on riverbanks for 100 linear meters were plastic, which was much lower than on beaches (around 80% for 100 linear meters). This result is consistent with another study in Chili showing that plastics were the prevailing litter items and were more frequently found on beaches than on riversides (Rech et al., 2015). Another national study on German riverbanks found similar proportion of plastics among all debris (51%, including 20% of cigarette butts) (Kiessling et al., 2019). Other studies at local or regional scales found much higher proportions of plastics among all debris in the Adour riverbank (94%) and closed beaches (95%) (Bruge et al., 2018) or in the riverbanks of the Dutch Rhine-Meuse delta (85%) (Van Emmerik & Schwarz, 2020). Such discrepancy may be explained by local or regional disparities on the number of other types of debris (glass, metal, ceramics, paper, wood, rubber and textile) and on the modest sampling effort. In our case, a significant percentage of all debris on riverbanks were made of glass and metals, thus explaining the higher weight of all debris on riverbanks compared to beaches (median of 10 kg and 5 kg for 100 linear meters, respectively). These non-buoyant litter items are frequently attributed to non-riverine sources like direct litter dumping (Bravo et al., 2009), by opposition to the high abundance of plastic items that in addition can be transported by rivers and deposited on riverbanks due to their buoyancy and extreme persistence (Derraik, 2002; Moore, 2008). Detailed plastic litters analysis in relation to their origin Single-use plastics together with packaging (bags and wrappers) dominated most of the riverbanks (around 44.4%), in a higher proportion than on beaches (around 32.9%). In particular, food-related items dominated the top 10 single-use plastics. It was dominated by caps (mainly from plastic bottles) and thin wrapper on both riverbanks and beaches. Drink containers, shopping bags and food containers were found in higher proportions on riverbanks, despite they were also present on beaches. Most of these items are typically used by individuals and are classically found on riverbanks (Al-Zawaidah et al., 2021) and beaches (Lacroix et al., 2022). Either thrown away because of incivility (close to “take-away” restaurants), involuntary loss, or mismanagement (discarded during collection operations or transport by local authorities), they are ending up on city grounds, pushed away by the wind and runoff to rainwater collection systems which take them either straight to the closest river or to the next Waste Water Treatment Plant (WWTP) (Bruge et al., 2018). Cigarette butts, lollipop sticks and cotton swabs were found in higher proportions on beaches compared to riverbanks, probably due to incivility. Indeed, it has been shown that cigarette butts may not be considered littering by many smokers (Rath et al., 2012). As for the former three items, marine activities-related items (rope, buoys, floats, lures/lines, packaging straps) were much more present on beaches (24.9 ± 21.7%) than on riverbanks (4.5 ± 9.8%), probably reflecting the importance of higher losses from professional and recreative fishing activities in the marine environment in France. Together with fishing gears lost at sea during storms, discarding damaged nets is a common practice that results in debris accumulation on beaches or seafloor, close to zones of high fishing activity such as the north and south-west of the Gulf of Lion, and in the South Brittany region (Galgani et al., 2000). Here, we observed that around 87% of marine litter originated from land-based uses, which is consistent with classically found at a global scale (GRID-Arendal, 2016; Conservancy, 2017). Together with the numerous broken glass and sharp metal objects, sanitary and medical litters represented a smaller portion of all the riverbanks litters (around 5%), but higher than uncounted on beaches (around 0.8%). They represent potentially dangerous items to human health, together with other items that were found less frequently such as decomposing food leftovers (which could attract disease-carrying animals or harm small children upon accidental ingestion) and litter items containing chemicals (e.g. aerosol cans, batteries, paint containers) (Kiessling et al., 2019). A specific awareness was given in the support guide, in the protocol guide and in the photoguide of Plastique à la Loupe initiative, to prevent risks for schoolchildren participants during sampling and sorting. Litter types classified as “others” represented a significant proportion of all debris (10.5 ± 16.9 and 10.8 ± 17.9% on riverbanks and beaches, respectively). They included car parts, electronics, oil drums, batteries, etc. Attribution to this category is part of the OSPAR data collections scheme (OSPAR, 2020) and we decided to retain these data in our analyses. It diminished our ability to identify the source of litters, and we recognize that there are challenges regarding the source allocations for this category; yet, it gives information on macrolitters fragmentation, since the corresponding items are still recognizable. Photographs could have been used to go deeper in one specific item, but it is time consuming. Interestingly, macroplastic fragments (> 2.5 cm) was the second dominant plastic type collected on riverbanks (23.2 ± 24.8%) despite it dominated the plastic debris on beaches (28.7 ± 24.5%). Fragmented plastic is a direct result of weathering and photodegradation, resulting in surface embrittlement and microcracking, yielding particles that are carried into the closest river or the next WWTP by wind and runoff to rainwater collection systems and also by wind and wave action when transported to beaches (Andrady, 2011). They mainly consist of foam, hard and soft fragments, of which their original item identity remains unknown. Overall the detailed litter analysis provided more information to identify specific sources of (plastic) litter, and support policy-makers to implement prevention measures targeted at specific items. Macro-, meso- and microplastics To date, studies on microplastics mainly concerned ones floating at sea, while land-based studies of the stranded plastic litters on riverbanks and beaches focused more on macro- and mesoplastics (Vriend et al., 2020). Very few data exist on the comparison of all plastic sizes, despite a growing interest on understanding the “plastic cycle” (Hoellein & Rochman, 2021). The Plastique à la loupe initiative offers the possibility of tracking the different plastic sizes in a large set of riverbanks and beaches data. Tracing the source of plastics was possible only for a small proportion of the numerous collected items, mainly for identifiable macroplastics (25.8 ± 29.7% of all plastic size on riverbanks and 11.7 ± 19.0% on beaches) and microplastic pellets (13.1 ± 22.4% on riverbanks and 13.3 ± 19.5% on beaches). Most of the plastic items were non identifiable, resulting from the fragmentation of macroplastics into meso- and microplastics by breaking down in smaller size after exposure to ultraviolet light or mechanical forces once lost in the environment (Weinstein et al., 2016). Mesoplastics, originating from macroplastics fragmentation, represented a lower proportion of total plastic items on riverbanks than on beaches (21.7 ± 25.9% and 35.9 ± 22.0% respectively). However, it was difficult to conclude on any relation between the abundance of fragmented plastic litters and the distance to the sea from our current dataset, because of the lack of sufficient number of sites per river. We observed that abundances of meso- and micro-plastics were the most strongly correlated in both riverbanks and beaches. Numbers of macro- and microplastics, and meso- and microplastics were positively correlated on both riverbanks and beaches. On beaches, there was a higher correlation between the abundances of meso- and microplastics than between macro- and microplastics (r s = 0.4, p -value = 6.2 x 10 − 3 ; r s = 0.7, p -value = 7.7 x 10 − 9 ), which is congruent with previous studies (Lee et al. 2013). The evaluation of the number of mesoplastics was proposed to serve as a better proxy of microplastic pollution than macroplastics, thus helping easier surveys to identify hot spots of microplastic pollution in large geographical areas with limited resources (Lee et al. 2013). That was not the case on riverbanks, where correlations between meso- and microplastics gave the same values than between macro- and microplastics (r s = 0.51, p -value = 1.1 x 10 − 5 for both tests). Microplastics represented a major part of the number of plastics found on both riverbanks (47.0 ± 34.2% of all plastic debris) and beaches (45.7 ± 25.5%). On riverbanks, a large proportion of microplastics were made of polystyrene (43%), which is congruent with previous results showing that such floating plastics tend to beach sooner and accumulate on riverbanks or lake beaches due to wind effects (Corcoran, 2015). On marine beaches, polyethylene dominated the microplastics (61.1%), as classically found in seawaters (Erni-Cassola et al., 2019). Interestingly, we observed on both riverbanks and beaches that a quarter of the microplastics were made of industrial pellets (primary microplastics, also known as virgin pellets or nurdles, recognized by their regular shape, usually cylindrical or ovoid), which form the feedstock of the plastics industry. These pellets enter the environment when they are spilled accidentally, either on land or at sea. Previous observation mentioned the clear link between the presence of industrial pellets and the vicinity to urban-industrial centers or in relation to accidental leakage during transport (Ryan et al., 2018). Conclusion Previous mathematical model based on estimations of river discharge and mismanaged plastic waste resulted in a total global riverine emission of plastics into the ocean in the range of million metric tons per year (Lebreton et al., 2017; Schmidt et al., 2017). A recent study based on in-depth statistical reanalysis of updated data on microplastics demonstrated that current river flux assessments are overestimated by two to three orders of magnitude (Weiss et al., 2021). Such discrepancy demonstrates the need for more field data to improve the modeling estimation to quantify land-based marine debris transport into the ocean. Monitoring all plastics sizes (macro-, meso- and microplastics) both in riverine and marine environments is a prerequisite for understanding how plastic is transported and where it accumulates, as well as how fragmentation occurs. This study presents the power of the Plastique à la loupe initiative that follows the recent recommendation for harmonization of monitoring efforts on riverbanks (Vriend et al., 2020), as previously done for floating macroplastics through the RIMMEL project (González-Fernández & Hanke, 2017). Consistent and harmonized sampling and quantification methodologies are required to gather comparable data from the increasing number of scientific and citizen science initiatives around the world. This study presents the first two years data of the Plastique à la loupe initiative in France that is still running for the next coming years with the same protocol and with higher national coverage, both in metropolitan and overseas territorial departments. Schoolchildren removed more than 55,980 pieces of plastic from riverbanks and beaches in two years and prevented the formation of millions of micro- and nanoplastics through degradation over time (Ryan et al., 2020). The increasing number of classes per year (50 in 2019, 150 in 2020, 300 in 2021, 450 in 2022) in the Plastique à la loupe initiative will undoubtedly contribute to the incredibly valuable litter collecting by citizens over the world (European Environment Agency, 2018) and to detect meaningful trends in litter volumes over time on riverbanks and beaches. Engagement went beyond riverbanks or beach clean-ups and instead the Plastique à la loupe initiative was used as a tool to bridge gaps between communities and scientists, while also raising awareness of the plastic pollution, increasing schoolchildren interest for science and inspiring solutions to act. Declarations -Ethical Approval: This article follows the Committee on Publication Ethics (COPE) guidelines, including the ethical responsibilities of authors. The authors declare that they obtained study-specific approval by the appropriate ethics committee for research content of this article. -Consent to Participate: All authors agreed to participate to the co-authorship. The authors have no competing interests to declare that are relevant to the content of this article. -Consent to Publish: All co-authors agreed with the content of this article and they all gave explicit consent to submit. They obtained consent from the responsible authorities at the institute/organization where the work has been carried out, before the work has been submitted. -Author Contributions (CRediT taxonomy): Léna Philip: Investigation, Methodology, Visualization, Writing - original draft, review & editing; Maëla Le Picard : Investigation, Methodology, Visualization, Writing - review & editing; Edouard Lavergne: Investigation, Methodology, Visualization, Writing - review & editing; Pascaline Bourgain: Conceptualization, Project administration, Resources, Supervision, Writing - review & editing; Brigitte Sabard: Conceptualization, Funding acquisition, Project administration, Resources, Supervision, Writing - review & editing; Romain Troublé: Funding acquisition, Project administration, Supervision, Writing - review & editing; Anne-Leila Meistertzheim: Conceptualization, Funding acquisition, Investigation, Methodology, Supervision, Visualization, Writing - review & editing; Wolfgang Ludwig: Conceptualization, Methodology, Visualization, Writing - review & editing; Alexandra ter Halle: Conceptualization, Methodology, Visualization, Writing - review & editing; Camille Lacroix: Conceptualization, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Visualization, Writing - review & editing; Jean-François Ghiglione: Conceptualization, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Visualization, Writing - original draft, review & editing. -Funding: This work was supported by the grant PLASTRANSFER supported by the French Agency for Ecological Transition (ADEME) and the French Biodiversity Agency (OFB) and by the European Union’s Horizon 2020 research and innovation project AtlantECO under grant agreement No 862923. -Competing Interests: The authors have no relevant financial or non-financial interests to disclose . -Availability of data and materials: The datasets and materials used and/or analyzed during the current study are available on reasonable request. 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Mediterraneens","correspondingAuthor":false,"prefix":"","firstName":"Wolfgang","middleName":"","lastName":"Ludwig","suffix":""},{"id":272533846,"identity":"7bde3536-29ba-4d4f-a550-6c30e7054a03","order_by":8,"name":"Alexandra ter Halle","email":"","orcid":"","institution":"Toulouse III University-Paul Sabatier: Universite Toulouse III-Paul Sabatier","correspondingAuthor":false,"prefix":"","firstName":"Alexandra","middleName":"ter","lastName":"Halle","suffix":""},{"id":272533847,"identity":"ba8d0add-e777-4d94-8ce0-6794cf5200ac","order_by":9,"name":"Camille Lacroix","email":"","orcid":"","institution":"Centre de documentation de recherche et d'expérimentations sur les pollutions accidentelles des eaux","correspondingAuthor":false,"prefix":"","firstName":"Camille","middleName":"","lastName":"Lacroix","suffix":""},{"id":272533848,"identity":"d32ee13f-c83e-4720-9801-a5e1945e2aa1","order_by":10,"name":"Jean-Francois Ghiglione","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABDElEQVRIiWNgGAWjYDACCcYGhgcGQAZ7AxuQPAASYwSScvi1JIC08ByAawGRxni0AHECmJFApBb56ObmFwkFNnn8ko+PPfzBcEfeXCLH4OAPBoN8XFoM7xxss0gwSCuWnJ2WbszD8Mxw54wcg8M8DAaWDbi0zEhsM0gwOJy44XaOmTTjv8OMG24AtTAw/DHAaQtMy/6bZ8wkfzActgdpATkMpxZ5icTmB2BbJHjMJHgYgAyglgM8eLQYSCS2AQM5LXHGGYhfkjeceVZwmMcAjy0z0h9/+PDHJrG//TA4xGw3HE/e+PBHBR5bDjCwSaAKCSSAxHFpANrSwMD8AVWI/wBu5aNgFIyCUTAiAQAlnmCv5avkAAAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-7475-2262","institution":"LOMIC: Laboratoire d'Oceanographie Microbienne","correspondingAuthor":true,"prefix":"","firstName":"Jean-Francois","middleName":"","lastName":"Ghiglione","suffix":""}],"badges":[],"createdAt":"2024-01-16 18:35:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3870685/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3870685/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11356-024-35506-w","type":"published","date":"2024-11-13T15:57:14+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":51113398,"identity":"b97c4ad4-7847-4bbe-88cb-e5d231b32c75","added_by":"auto","created_at":"2024-02-14 10:30:17","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1338236,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTotal number of litters per site sampled in 2019-2020 (A) and 2020-2021 (B).\u003c/strong\u003e Beaches are represented with blue dots; riverbanks are represented with orange dots. The number of litters correspond to the sum of macrolitter, meso- and microplastics, normalized for 100 linear meters.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/69ce7a8aded5be3b8db4e92d.png"},{"id":51113026,"identity":"8097d585-1317-4803-b36d-e9c0c5dd08d6","added_by":"auto","created_at":"2024-02-14 10:22:17","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":230652,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSampling units for macrolitters, meso-and microplastics on riverbanks and beaches in situation with (A) and without wrack lines (B).\u003c/strong\u003e Grey shaded areas represent the sampling space of macrolitter and black dashed lines the sampling spaces of meso- and microplastics (adapted from Vriend et al., 2020).\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/d2f1718677c780be7ed71c73.png"},{"id":51113027,"identity":"3ae4ba5d-00e2-4735-9462-95952c864ce8","added_by":"auto","created_at":"2024-02-14 10:22:17","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":178707,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eNumber of macrolitters for 100 linear meters (A) \u003c/strong\u003e(left: riverbanks, n=81; right: beaches, n=66), m\u003cstrong\u003eass of macrolitters, in kg for 100 linear meters (B) \u003c/strong\u003e(left: riverbanks, n=67; right: beaches, n=52) and \u003cstrong\u003eproportions of types of macrolitters (C) \u003c/strong\u003e(top: riverbanks, n=81; bottom: beaches, n=66).\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/daaa283f95b3c4fd64bd5490.png"},{"id":51113033,"identity":"75ff5b27-4e66-4dcd-8896-55370002cdf3","added_by":"auto","created_at":"2024-02-14 10:22:17","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":259814,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTypes of plastics and single-use plastics on riverbanks (A and C respectively, n = 81) and beaches (B and D respectively, n = 66). \u003c/strong\u003eThe mean proportion on all sites for each item category are presented. The category “other items” in A and B correspond to recognizable macroplastics that were not detailed in the survey form. The category “others” in C and D comprises foamed polystyrene food containers and cups, tampon and applicators, disposable plates and cutleries, and stirrers. These former items were found in proportions \u0026lt; 1 %, except for foamed polystyrene food containers on beaches.\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/49e361a3beaab297730335e8.png"},{"id":51113032,"identity":"2fc3af59-b4c2-4e86-bd30-897c9bb41024","added_by":"auto","created_at":"2024-02-14 10:22:17","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":229157,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSize fractions of plastic litters. \u003c/strong\u003eThe mean proportions for each size category are represented for all riverbanks on top (n=67) and all beaches on the bottom (n=51).\u003c/p\u003e","description":"","filename":"Figure5.png","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/94d7228c72c59b63bcbb53dc.png"},{"id":51113399,"identity":"801a07b5-594c-455c-8411-19f21fb944d4","added_by":"auto","created_at":"2024-02-14 10:30:17","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":135046,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eNature of microplastics on A. Riverbanks and B. Beaches. \u003c/strong\u003eThe mean proportions for each chemical category are represented for riverbanks (n=49) and beaches (n=39).\u003c/p\u003e","description":"","filename":"Figure6.png","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/ba84c645659f647a877a8722.png"},{"id":69274957,"identity":"4c828779-0cb3-4332-86f9-bd8ae1f96907","added_by":"auto","created_at":"2024-11-18 16:41:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2887606,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/fdd3ae7d-7ca6-42ab-b845-d152225a8b68.pdf"},{"id":51113029,"identity":"944b1497-777b-4505-ac92-ee27a0e8a57e","added_by":"auto","created_at":"2024-02-14 10:22:17","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":1171411,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryTextTablesandFigures.docx","url":"https://assets-eu.researchsquare.com/files/rs-3870685/v1/c9e84579a7426592947ad051.docx"}],"financialInterests":"","formattedTitle":"Comparison of the macro-, meso- and microplastic pollution in French riverbanks and beaches using citizen science with schoolchildren","fulltext":[{"header":"Introduction","content":"\u003cp\u003ePlastic pollution has been documented in all major ocean basins and a growing number of freshwater and terrestrial environments (Bucci et al., 2020). Despite a growing literature in the last decade, the ultimate fate of plastic debris and its transport mechanisms in terrestrial, freshwater, and marine environments are poorly understood, at both regional and global levels (Zhu, 2021). There is a peculiar, several orders of magnitude mismatch between projected litter emissions into the ocean (Jambeck et al., 2015) and global estimates based on field data (Van Sebille et al., 2015), indicating hitherto insufficiently accounted sinks such as remote beaches and riverbanks (Bergmann et al., 2017).\u003c/p\u003e \u003cp\u003eThe importance of tackling plastic litter worldwide has been globally recognized in the context of the 2030 agenda for sustainable development, adopted by all United Nations Member States in 2015 (see target 14.1 in United Nations, 2015). In the marine environment, plastic litter is one of the 11 descriptors of Good Environmental Status (GES) of the European Marine Strategy Framework Directive (2008/56/EC, MSFD) (Galgani et al., 2013). In freshwater, contamination by plastic litters has not yet been considered as a descriptor of good environmental status, including for example the European Water Framework Directive (2000/60/EC, WFD). This gap could be explained by the lack of data relating the occurrence and associated effects of plastic contamination in freshwater ecosystems (Dris et al., 2015). Several studies recognized that plastics with terrestrial usages are the main sources of marine plastic pollution, either by direct emission from coastal zones (Li et al., 2021) or transport through rivers (Lebreton et al., 2017; Schmidt et al., 2017; Weig et al., 2021). Riverine plastic transport remains understudied and the better understanding of the sources and pathways of plastics in freshwater ecosystems is a prerequisite to develop effective prevention and collection strategies.\u003c/p\u003e \u003cp\u003eGathering sufficient data for scientific research is challenging, with limited sampling time and human resources involved in classical scientific projects (Zettler et al., 2017). Because marine litters are easily identifiable and their quantification requires relatively little scientific training, it is particularly well suited for engaging citizen scientists to expand our knowledge of the spatial and temporal distribution of marine litter, especially in remote, under-sampled areas (Hidalgo-Ruz \u0026amp; Thiel, 2015). In addition to data provisioning, citizen engagement serves as an outreach mechanism to inform and involve the general public on scientific progress (Silvertown et al., 2013). An increasing number of citizen science initiatives exist on plastic litter, mainly focusing on macro- and microplastics washed or deposited on beaches or shorelines (beach litter) in the United States (Barrows et al., 2018; Uhrin et al., 2020), China (Chen et al., 2020), Indonesia (Syakti et al., 2017), United Kingdom (Nelms et al., 2020), Danemark (Syberg et al., 2020), British Columbia and Canada (Harris et al., 2021), Chili (Bravo et al., 2009), Australia (Carbery et al., 2020; van der Velde et al., 2017), Svalbard (Bergmann et al., 2017), and Lofoten Island (Haarr et al., 2020). Other initiatives with focus on floating plastic debris were carried out in the United States (Davis \u0026amp; Murphy, 2015), Sweden (Gewert et al., 2015) and Taiwan (Chiu et al., 2020). Studies on plastic debris on the seafloor were conducted in the United Kingdom (Nel et al., 2020) and across 13 countries in Europe (Lots et al., 2017). Surprisingly, none of these initiatives considered riverbanks despite the need of data on plastic quantification at the source of the pollution.\u003c/p\u003e \u003cp\u003ePlastic debris encompass a wide size distribution, from large abandoned and derelict consumer litters (often single-use products) to unrecognizable fragments of meso- (from 25 mm to 5 mm) and microplastics (5 mm to 500 \u0026micro;m) (Hinata et al., 2017). Several methodologies for monitoring marine litter already exist. Among them, the OSPAR beach litter protocol is one of the most used to monitor macrolitter on beaches (OSPAR, 2020) and it has been adapted to monitor macrolitter on riverbanks (Van Emmerik \u0026amp; Schwarz, 2020).\u003c/p\u003e \u003cp\u003eThis study presents the first citizen science initiative dedicated to the comparison between macro-, meso- and microplastic debris on riverbanks and beaches. \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e is also the first initiative conducted in France, engaging 3,113 teenagers and their teachers from 149 schools across the nation collecting and extracting samples since 2019. Here, we focused on assessing the composition, distribution and abundance of plastic debris on riverbanks and beach surveys in France from data collected between 2019 and 2021 (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Schoolchildren have used the same scientific protocol as developed during the Tara Microplastic expedition, adapted from the OSPAR protocol (Ghiglione et al., 2023). We ended up with 43,571 macro- and mesoplastic items that were characterized together with 12,415 microplastics for analysis by Fourier transform infrared spectroscopy (FTIR). This study confirms the potential of using citizen science for relevant analysis of macro-, meso- and microplastic pollution on riverbanks and beaches.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy sites\u003c/h2\u003e \u003cp\u003e Study sites were first chosen by teachers based on local experience and further validated by the scientific committee. Selection criteria were defined from OSPAR and MSFD recommendations and adapted to the citizen science format in order to guarantee the safety of participants and the quality of the data collected (OSPAR, 2020; MSFD TG ML, 2013), including: (1) absence of danger, (2) easy access, (3) presence of deposited litter, (4) absence of cleaning in the 15 days before the sampling, (5) minimum length of 10 m for riverbanks and 50 m for beaches, (6) presence of sand for microplastic sampling. A total of 81 riverbanks and 66 beaches were visited by 149 classes from middle to high school (11 to 18 years old). Sampling sites were spread over the whole French metropolitan territory, in 17 of the 30 academies of the French Ministry of National Education (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The classes sampled in the field between September and March 2019\u0026ndash;2020 and 2020\u0026ndash;2021. Each class was asked to fill a site description form (adapted from the OSPAR beach litter monitoring form; OSPAR, 2010). Information collected includes orientation of the site, sand granulometry, uses (seasonal/annual), accessibility and nature of the site's surroundings (town, village, port, estuary, landfill sites, sewage treatment plant, etc.) as well as the frequency and method of cleaning (if relevant) (Supplementary data 1).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eStranded macrolitters\u003c/h2\u003e \u003cp\u003eStranded macrolitters were surveyed using a method adapted from the OSPAR methodology (OSPAR 2020), with a slight difference depending on whether sites presented wrack lines. On a section with a known length ranging from 10 to 100 m and located from the first wrack line near the river or coast to the back of the riverbank or beach, classes collected all visible litters larger than 2.5 cm (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). In the absence of a visible wrack line, sampling was made on the whole width of the riverbank or beach across the section (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB).\u003c/p\u003e \u003cp\u003eThe collected litter was placed in bin bags, except for items that were too large or too heavy, which were left on site and noted for later counting. Collected litter was brought back to the classroom, for estimation of the volume (L) and measurement of the mass (kg) of total macrolitter. Each litter was sorted, identified and counted according to the OSPAR beach litter survey data form, enriched with additional litter types such as Covid19 crisis related items (disposable mask\u0026hellip;) and reorganized by item uses categories (fishing related, medical\u0026hellip;) to assist the macrolitter identification. Some items including single used plastic items (straws, lolly sticks,\u0026hellip;) and foamed polystyrene fragments were separated for a better focus. The survey data form describing the different categories, types and uses, is presented in supplementary data (Supplementary data 2). A picture was taken once all litters were sorted, and litters were then disposed according to their composition in the appropriate waste disposal center. Results obtained were expressed in volume, mass and number for 100 linear meters of riverbank or beach, 100 meters being the survey unit adopted for OSPAR and MSFD assessments of beach litter (OSPAR, 2020, MSFD TG ML, 2023). The calculation was performed by dividing the data obtained by the number of linear meters surveyed and multiplying by 100. Data normalization was done relative to 100 linear meters rather than surfaces in order to avoid the bias induced by tides, which changes the surface of the sampling area depending on the time of the sampling and therefore, the density of items on the beach.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStranded meso- and large microplastics\u003c/h2\u003e \u003cp\u003eStranded mesoplastics and large microplastics were assessed using a method proposed at the European level to monitor mesolitter fragments and pellets on the coastline (MSFD TG ML, 2023). The protocol consists in delimiting three 50 cm-wide bands evenly distributed over the macrolitter section, and sampling along these three bands, perpendicularly to the water line, either on each wrack line (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA) or on the whole riverbank or beach width in the absence of visible wrack lines (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). Materials used for sampling were made of metal or glass to prevent any sample contamination. Samplings were done by collecting sand surface using a trowel on the three bands. To limit organic matter and sand collection, meso- and microplastics were extracted directly on site, by flotation in either seawater (for coastal sites) or freshwater (for river sites). Floating particles were recovered with a metallic cooking sieve with a mesh size of 1 mm, then stored in a metal tray and brought back to class for sorting. Once in classroom, samples from the three subsamples were treated separately, by visually sorting organic debris and plastics. Plastics were then sorted according to their size class: mesoplastics [0.5; 2.5 cm] and large microplastics [0.1; 0.5 cm].\u003c/p\u003e \u003cp\u003e The particles were then counted according to their type (fibers, pellets, fragments...) and color based on a list adapted from MSFD microlitter monitoring guidelines (MSFD TG ML, 2023) as presented in the survey data form (Supplementary data 2). Meso- and microplastic lists were the same except for the industrial plastic pellets (IPP) category (also known as nurdle or pellet), which is only included in the microplastic list. Results were expressed in number of particles by 100 linear meters of riverbank or beach, by dividing the number of particles by 1.5 m (corresponding to 3x50 cm-wide bands) and multiplying by 100 m. After sorting, a picture of each sample was taken. 96 microplastics were then selected randomly in the sample and sent to the Observatoire Oc\u0026eacute;anologique de Banyuls sur mer (OOB, France) or to the Cedre (Brest, France), for polymer composition analysis by Fourier transformed infrared spectroscopy (FTIR). FTIR analyses were performed with following parameters: 32 scans, 4 of resolution and large scale from 4000 to 600 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Polymer identification was performed using the POSEIDON tool that contains a spectra bank obtained from microplastics collected during the Tara Mediterranean (2014) and Tara Microplastic (2019) expeditions (Ghiglione et al., 2023; Kedzierski et al., 2019).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eData management and analysis\u003c/h2\u003e \u003cp\u003eSurvey data forms were gathered for riverbanks and beaches, and raw data were normalized for 100 linear meters. Some sites were excluded from the analysis when the length of the sampling section was not mentioned by schools. Data from riverbanks and beaches were treated separately. For Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC, \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e and \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e, proportions were calculated from normalized data for each site, and the mean of theses proportions was calculated to have information on the dispersion of data. For plastic litter size analysis (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e), only the sites with complete sampling of macro-, meso-, and microplastics on a known section were studied.\u003c/p\u003e \u003cp\u003eCorrelations between numbers of macro-, meso-, and microplastics were calculated for riverbanks and beaches separately. Data normality was tested using a Shapiro test. Correlation indexes were calculated using the non-parametric Spearman test.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eNumber, mass and composition of macrolitters on riverbanks and beaches\u003c/h2\u003e \u003cp\u003eA total of 81 riverbanks from large and small rivers were sampled in France, together with 66 beaches located along the French coastline either on the coast of the Mediterranean Sea, the Atlantic Ocean or the English Channel). Among all the sites that were studied, only two were not polluted with macrolitter on the sampling zone; however, for one of these two sites, the area surrounding the sampling section was highly polluted, mainly with glass debris. The median number of macrolitters per 100 linear meters collected on riverbanks was approximatively twice lower (median\u0026thinsp;=\u0026thinsp;232 for 100 linear meters, n\u0026thinsp;=\u0026thinsp;81) than on beaches (median\u0026thinsp;=\u0026thinsp;443 for 100 linear meters, n\u0026thinsp;=\u0026thinsp;66) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA). Mean numbers of macrolitter per 100 linear meters were much higher than median numbers, on both riverbanks and beaches, due to extreme sites (1032\u0026thinsp;\u0026plusmn;\u0026thinsp;2147 macrolitter for 100 linear meters and 1276\u0026thinsp;\u0026plusmn;\u0026thinsp;2623 respectively). The opposite tendency was observed when expressing macrolitters by weight, in kg of litter per 100 linear meters (median\u0026thinsp;=\u0026thinsp;10.0 kg, n\u0026thinsp;=\u0026thinsp;67 sites and median\u0026thinsp;=\u0026thinsp;5.1 kg, n\u0026thinsp;=\u0026thinsp;52 sites per 100 linear meters on riverbanks and beaches, respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eB).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePlastic was the most dominant debris type in number of items compared to the total number of collected litters, with a lower proportion on riverbanks than on beaches (55.1\u0026thinsp;\u0026plusmn;\u0026thinsp;30.4 and 80.0\u0026thinsp;\u0026plusmn;\u0026thinsp;22.4% respectively). Other debris were composed of glass (16.3\u0026thinsp;\u0026plusmn;\u0026thinsp;20.8 and 8.4\u0026thinsp;\u0026plusmn;\u0026thinsp;17.8% respectively), metals (13.0\u0026thinsp;\u0026plusmn;\u0026thinsp;15.3 and 2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5% respectively), paper and cardboard (5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;9.1 and 1.2\u0026thinsp;\u0026plusmn;\u0026thinsp;2.2% respectively), ceramics (2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;7.9% and 1.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9% respectively), textiles (2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;5.0% and 1.1\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6% respectively), wood (1.5\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5% and 3.0\u0026thinsp;\u0026plusmn;\u0026thinsp;6.7% respectively) and rubber (0.9\u0026thinsp;\u0026plusmn;\u0026thinsp;2.7 and 2.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0% respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eCommon macroplastic types and composition on riverbanks and beaches\u003c/h2\u003e \u003cp\u003eMacroplastic debris found across all riverbanks (n\u0026thinsp;=\u0026thinsp;81 sites) were dominated by single-use disposable plastics (43.4\u0026thinsp;\u0026plusmn;\u0026thinsp;26.2%), whereas it represented only 27.6\u0026thinsp;\u0026plusmn;\u0026thinsp;17.4% on beaches (n\u0026thinsp;=\u0026thinsp;66 sites) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC). Plastic fragments were the second dominant plastic type collected on riverbanks (23.2\u0026thinsp;\u0026plusmn;\u0026thinsp;24.8%), despite it dominated the plastic debris on beaches (28.7\u0026thinsp;\u0026plusmn;\u0026thinsp;24.5%). Marine activities-related items (fishing, aquaculture and maritime gears) were more present on beaches (24.9\u0026thinsp;\u0026plusmn;\u0026thinsp;21.7%) than on riverbanks (4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;9.8%). Inversely, bags and wrappers were more abundant on riverbanks (11.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.5%) compared to beaches (5.3\u0026thinsp;\u0026plusmn;\u0026thinsp;7.9%). The same trend was found for sanitary and medical items (3.0\u0026thinsp;\u0026plusmn;\u0026thinsp;10.1% and 2.7\u0026thinsp;\u0026plusmn;\u0026thinsp;12.0% respectively on riverbanks and \u0026lt;\u0026thinsp;0.6% on beaches). A significant number of unclassified items (recognizable items that were not listed in the survey data form) were found on both riverbanks (10.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.9%) and beaches (10.8\u0026thinsp;\u0026plusmn;\u0026thinsp;17.9%) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB), limiting the description of macrolitters on the studied sites.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eFocus on single-use disposable plastics on riverbanks and beaches\u003c/h2\u003e \u003cp\u003eSingle-use disposable plastics represented 43.3\u0026thinsp;\u0026plusmn;\u0026thinsp;26.2% and 27.6\u0026thinsp;\u0026plusmn;\u0026thinsp;17.4% of all macrolitter on riverbanks and beaches respectively. They were dominated by thin wrappers and caps on both riverbanks (20.5\u0026thinsp;\u0026plusmn;\u0026thinsp;28.1% and 15.7\u0026thinsp;\u0026plusmn;\u0026thinsp;23.1%, respectively) and beaches (18.7\u0026thinsp;\u0026plusmn;\u0026thinsp;19.8% and 24.1\u0026thinsp;\u0026plusmn;\u0026thinsp;23.2%, respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eD). Drink containers, shopping bags and food containers were found in higher proportions on riverbanks (12.3\u0026thinsp;\u0026plusmn;\u0026thinsp;18.8%, 8.2\u0026thinsp;\u0026plusmn;\u0026thinsp;19.3% and 4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;9.5 respectively), despite they were also present on beaches (6.4\u0026thinsp;\u0026plusmn;\u0026thinsp;15.3%, 3.9\u0026thinsp;\u0026plusmn;\u0026thinsp;10.9% and 1.2\u0026thinsp;\u0026plusmn;\u0026thinsp;3.9%, respectively). Inversely, cigarette butts, lollipop sticks and cotton swabs were found in higher proportions on beaches (17.2\u0026thinsp;\u0026plusmn;\u0026thinsp;21.6%, 11.2\u0026thinsp;\u0026plusmn;\u0026thinsp;13.0% and 6.5\u0026thinsp;\u0026plusmn;\u0026thinsp;15.2%, respectively) compared to riverbanks (12.6\u0026thinsp;\u0026plusmn;\u0026thinsp;24.0%, 5.8\u0026thinsp;\u0026plusmn;\u0026thinsp;16.8 and 1.1\u0026thinsp;\u0026plusmn;\u0026thinsp;4.7%, respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eD).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eComparison between macro-, meso- and microplastics on riverbanks and beaches\u003c/h2\u003e \u003cp\u003eMicroplastics represented a major part of the number of plastics found on both riverbanks (47.0\u0026thinsp;\u0026plusmn;\u0026thinsp;34.2%, n\u0026thinsp;=\u0026thinsp;67 sites) and beaches (45.7\u0026thinsp;\u0026plusmn;\u0026thinsp;25.5%, n\u0026thinsp;=\u0026thinsp;51 sites) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). It is noteworthy that the industrial plastic pellets (IPP) itself represented around a quarter of the microplastics found on riverbanks and beaches (22.5\u0026thinsp;\u0026plusmn;\u0026thinsp;28.1% and 25.2\u0026thinsp;\u0026plusmn;\u0026thinsp;28.1% of sampled microplastics respectively, corresponding to 13.1\u0026thinsp;\u0026plusmn;\u0026thinsp;22.4% and 13.3\u0026thinsp;\u0026plusmn;\u0026thinsp;19.5% of total plastics, respectively), while the rest of microplastics was mostly dominated by fragmented pieces. The second most dominant plastics on riverbanks were fragmented mesoplastics (21.7\u0026thinsp;\u0026plusmn;\u0026thinsp;25.9% and 35.9\u0026thinsp;\u0026plusmn;\u0026thinsp;22.0% of total plastics on riverbanks and beaches, respectively). On beaches, macroplastics were found in lowest proportion (16.8\u0026thinsp;\u0026plusmn;\u0026thinsp;24.7%), whereas it represented 31.3\u0026thinsp;\u0026plusmn;\u0026thinsp;31.4% of total plastics on riverbanks. Here, it is noticeable that a large proportion of macroplastics found on beaches were too fragmented to be identified (representing 6.6\u0026thinsp;\u0026plusmn;\u0026thinsp;13.6% of total plastics) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e), whereas the other part were recognizable macroplastics as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eChemical composition of microplastics on riverbanks and beaches\u003c/h2\u003e \u003cp\u003eSimilar polymer types were found for microplastics collected both on riverbanks (n\u0026thinsp;=\u0026thinsp;49 sites) and on beaches (n\u0026thinsp;=\u0026thinsp;39 sites), but with a clear difference in their relative proportions (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). On riverbanks, most of the microplastics were made of polystyrene (PS) and polyethylene (PE) (30.7\u0026thinsp;\u0026plusmn;\u0026thinsp;36.8% and 30.6\u0026thinsp;\u0026plusmn;\u0026thinsp;27.7 respectively) whereas beaches were clearly dominated by PE (52.1\u0026thinsp;\u0026plusmn;\u0026thinsp;26.2%). On beaches, PS and polypropylene (PP) were found in similar proportions (16.3\u0026thinsp;\u0026plusmn;\u0026thinsp;23.8% and 16.1\u0026thinsp;\u0026plusmn;\u0026thinsp;17.5% respectively). Among microplastics studied on riverbanks, only 6.4\u0026thinsp;\u0026plusmn;\u0026thinsp;12.7% were made of PP. Ethylene-vinyl acetate (EVA) represented only 1.6\u0026thinsp;\u0026plusmn;\u0026thinsp;5.2% and 0.8\u0026thinsp;\u0026plusmn;\u0026thinsp;2.4% on riverbanks and beaches respectively.\u003c/p\u003e \u003cp\u003eIt is noteworthy that a non-negligeable proportion of sampled micro-particles were natural ones, certainly mistaken for plastics when sorted out, representing the sampling error for microplastics (16.5\u0026thinsp;\u0026plusmn;\u0026thinsp;21.6% and 4.3\u0026thinsp;\u0026plusmn;\u0026thinsp;8.1% on riverbanks and beaches respectively). A proportion of microplastics was not identified (7.9\u0026thinsp;\u0026plusmn;\u0026thinsp;13.6% and 7.1\u0026thinsp;\u0026plusmn;\u0026thinsp;13.7% on riverbanks and beaches respectively) (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eAdding riverbanks to beaches citizen science monitoring for macrolitter, meso- and microplastics\u003c/h2\u003e \u003cp\u003eMonitoring efforts for stranded debris have mostly focused on beaches (Serra-Gon\u0026ccedil;alves et al., 2019). Riverbanks are constantly supplied with plastic debris from the rivers, driving the need for more research and management of marine debris. Riverbanks were poorly investigated, with generally very few numbers of studied sites per river (Bruge et al., 2018; Rech et al., 2015). Only one study involved a large number of sites in German rivers, by involving citizen science with schoolchildren (Kiessling et al., 2019).\u003c/p\u003e \u003cp\u003eCitizen science monitoring provides a baseline understanding of debris composition, concentration and sources, and helps inform policies to reduce environmental impacts of plastic debris (Nelms et al., 2022). Numerous initiatives exist all around the world (Kawabe et al., 2022), but this study provides the first citizen science initiative for a comparison between debris found on riverbanks and beaches. This baseline study presents the application of debris citizen science monitoring called \u0026ldquo;\u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e\u0026rdquo; to establish the first large-scale and long-term debris dataset for France, making it accessible to facilitate cost effective research efforts. In this study, conscientious collection by 3,113 schoolchildren from 149 classes removed a total of 48,023 macrolitters on riverbanks (n\u0026thinsp;=\u0026thinsp;81 sites) and beaches (n\u0026thinsp;=\u0026thinsp;66 sites) in two years. This labor-intensive monitoring effort would not have been feasible by a group of scientists, thus underlying the power of the \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e citizen science initiative for a French national survey. Since 2022, this dataset is used as complementary data in national assessments of aquatic litter pollution conducted by Cedre for French authorities in the context of the MSFD or other international monitoring programs.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eData quality controls\u003c/h2\u003e \u003cp\u003eParticipants were provided with support documents and visioconferences twice a year (by groups of 10 to 20 classes), allowing to gain confidence in their data-collection skills which was critical. The support document tool kit for teachers included (i) a support guide to explain the general concepts and objectives of the \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e initiative together with answer to frequently asked questions (FAQ), (ii) an easy and straightforward protocol guide slightly adapted from the OSPAR beach litter monitoring form (OSPAR, 2010), (iii) a photoguide for the macrolitter identification and (iv) a video guide for \u003cem\u003ein situ\u003c/em\u003e training. The reliability of the sampling area chosen by the teachers was also verified by the scientists for each class. In addition, at the beginning of the schoolyear, the teams of teachers involved benefited from a one day formation to the project in the presence of the educational team of the Tara Ocean Foundation.\u003c/p\u003e \u003cp\u003eA main concern regarding citizen-science studies is whether the collected data are reliable and comparable to professional studies. In order to test the reliability of the sampling, sorting and data acquisition, 8 sampling sites (6 on riverbanks and 2 on beaches) were first analyzed by scientists (without removing plastics) before the on-site visit of schoolchildren and comparison showed no or very little difference for mesoplastics and macrolitter (data not shown). No significant difference with results gathered by experienced scientists was found in other citizen science studies performing similar data quality control (Thiel et al., 2013). However, more errors were found by the schoolchildren for the microplastics with non-plastic particles representing around 7% of the total number of microplastics on riverbanks and beaches. As previously observed, it was found that glass shards for example had been misidentified as small plastic debris (Hidalgo-Ruz \u0026amp; Thiel, 2015). This error can be easily corrected by the FTIR analysis that helps to detect non-plastic particles, which mitigates the impact of such error on the results.\u003c/p\u003e \u003cp\u003eOnce the sampling site validation step was performed by scientists, only one site was excluded from the analysis for the length of the section was missing, thus underlying the high levels of coordination and personal motivation. Here, we underlined the importance of several steps including encouraging schoolchildren and teachers to describe any uncertainties to researchers, data auto-evaluation and communication of results as a concluding activity to enhance their commitment to the activity.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eDistribution and composition of all debris on riverbanks and beaches\u003c/h2\u003e \u003cp\u003eWe observed that around 55% of all debris collected on riverbanks for 100 linear meters were plastic, which was much lower than on beaches (around 80% for 100 linear meters). This result is consistent with another study in Chili showing that plastics were the prevailing litter items and were more frequently found on beaches than on riversides (Rech et al., 2015). Another national study on German riverbanks found similar proportion of plastics among all debris (51%, including 20% of cigarette butts) (Kiessling et al., 2019). Other studies at local or regional scales found much higher proportions of plastics among all debris in the Adour riverbank (94%) and closed beaches (95%) (Bruge et al., 2018) or in the riverbanks of the Dutch Rhine-Meuse delta (85%) (Van Emmerik \u0026amp; Schwarz, 2020). Such discrepancy may be explained by local or regional disparities on the number of other types of debris (glass, metal, ceramics, paper, wood, rubber and textile) and on the modest sampling effort. In our case, a significant percentage of all debris on riverbanks were made of glass and metals, thus explaining the higher weight of all debris on riverbanks compared to beaches (median of 10 kg and 5 kg for 100 linear meters, respectively). These non-buoyant litter items are frequently attributed to non-riverine sources like direct litter dumping (Bravo et al., 2009), by opposition to the high abundance of plastic items that in addition can be transported by rivers and deposited on riverbanks due to their buoyancy and extreme persistence (Derraik, 2002; Moore, 2008).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eDetailed plastic litters analysis in relation to their origin\u003c/h2\u003e \u003cp\u003eSingle-use plastics together with packaging (bags and wrappers) dominated most of the riverbanks (around 44.4%), in a higher proportion than on beaches (around 32.9%). In particular, food-related items dominated the top 10 single-use plastics. It was dominated by caps (mainly from plastic bottles) and thin wrapper on both riverbanks and beaches. Drink containers, shopping bags and food containers were found in higher proportions on riverbanks, despite they were also present on beaches. Most of these items are typically used by individuals and are classically found on riverbanks (Al-Zawaidah et al., 2021) and beaches (Lacroix et al., 2022). Either thrown away because of incivility (close to \u0026ldquo;take-away\u0026rdquo; restaurants), involuntary loss, or mismanagement (discarded during collection operations or transport by local authorities), they are ending up on city grounds, pushed away by the wind and runoff to rainwater collection systems which take them either straight to the closest river or to the next Waste Water Treatment Plant (WWTP) (Bruge et al., 2018). Cigarette butts, lollipop sticks and cotton swabs were found in higher proportions on beaches compared to riverbanks, probably due to incivility. Indeed, it has been shown that cigarette butts may not be considered littering by many smokers (Rath et al., 2012). As for the former three items, marine activities-related items (rope, buoys, floats, lures/lines, packaging straps) were much more present on beaches (24.9\u0026thinsp;\u0026plusmn;\u0026thinsp;21.7%) than on riverbanks (4.5\u0026thinsp;\u0026plusmn;\u0026thinsp;9.8%), probably reflecting the importance of higher losses from professional and recreative fishing activities in the marine environment in France. Together with fishing gears lost at sea during storms, discarding damaged nets is a common practice that results in debris accumulation on beaches or seafloor, close to zones of high fishing activity such as the north and south-west of the Gulf of Lion, and in the South Brittany region (Galgani et al., 2000). Here, we observed that around 87% of marine litter originated from land-based uses, which is consistent with classically found at a global scale (GRID-Arendal, 2016; Conservancy, 2017).\u003c/p\u003e \u003cp\u003eTogether with the numerous broken glass and sharp metal objects, sanitary and medical litters represented a smaller portion of all the riverbanks litters (around 5%), but higher than uncounted on beaches (around 0.8%). They represent potentially dangerous items to human health, together with other items that were found less frequently such as decomposing food leftovers (which could attract disease-carrying animals or harm small children upon accidental ingestion) and litter items containing chemicals (e.g. aerosol cans, batteries, paint containers) (Kiessling et al., 2019). A specific awareness was given in the support guide, in the protocol guide and in the photoguide of \u003cem\u003ePlastique \u0026agrave; la Loupe\u003c/em\u003e initiative, to prevent risks for schoolchildren participants during sampling and sorting.\u003c/p\u003e \u003cp\u003eLitter types classified as \u0026ldquo;others\u0026rdquo; represented a significant proportion of all debris (10.5\u0026thinsp;\u0026plusmn;\u0026thinsp;16.9 and 10.8\u0026thinsp;\u0026plusmn;\u0026thinsp;17.9% on riverbanks and beaches, respectively). They included car parts, electronics, oil drums, batteries, etc. Attribution to this category is part of the OSPAR data collections scheme (OSPAR, 2020) and we decided to retain these data in our analyses. It diminished our ability to identify the source of litters, and we recognize that there are challenges regarding the source allocations for this category; yet, it gives information on macrolitters fragmentation, since the corresponding items are still recognizable. Photographs could have been used to go deeper in one specific item, but it is time consuming.\u003c/p\u003e \u003cp\u003eInterestingly, macroplastic fragments (\u0026gt;\u0026thinsp;2.5 cm) was the second dominant plastic type collected on riverbanks (23.2\u0026thinsp;\u0026plusmn;\u0026thinsp;24.8%) despite it dominated the plastic debris on beaches (28.7\u0026thinsp;\u0026plusmn;\u0026thinsp;24.5%). Fragmented plastic is a direct result of weathering and photodegradation, resulting in surface embrittlement and microcracking, yielding particles that are carried into the closest river or the next WWTP by wind and runoff to rainwater collection systems and also by wind and wave action when transported to beaches (Andrady, 2011). They mainly consist of foam, hard and soft fragments, of which their original item identity remains unknown.\u003c/p\u003e \u003cp\u003e Overall the detailed litter analysis provided more information to identify specific sources of (plastic) litter, and support policy-makers to implement prevention measures targeted at specific items.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eMacro-, meso- and microplastics\u003c/h2\u003e \u003cp\u003eTo date, studies on microplastics mainly concerned ones floating at sea, while land-based studies of the stranded plastic litters on riverbanks and beaches focused more on macro- and mesoplastics (Vriend et al., 2020). Very few data exist on the comparison of all plastic sizes, despite a growing interest on understanding the \u0026ldquo;plastic cycle\u0026rdquo; (Hoellein \u0026amp; Rochman, 2021). The \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e initiative offers the possibility of tracking the different plastic sizes in a large set of riverbanks and beaches data. Tracing the source of plastics was possible only for a small proportion of the numerous collected items, mainly for identifiable macroplastics (25.8\u0026thinsp;\u0026plusmn;\u0026thinsp;29.7% of all plastic size on riverbanks and 11.7\u0026thinsp;\u0026plusmn;\u0026thinsp;19.0% on beaches) and microplastic pellets (13.1\u0026thinsp;\u0026plusmn;\u0026thinsp;22.4% on riverbanks and 13.3\u0026thinsp;\u0026plusmn;\u0026thinsp;19.5% on beaches). Most of the plastic items were non identifiable, resulting from the fragmentation of macroplastics into meso- and microplastics by breaking down in smaller size after exposure to ultraviolet light or mechanical forces once lost in the environment (Weinstein et al., 2016). Mesoplastics, originating from macroplastics fragmentation, represented a lower proportion of total plastic items on riverbanks than on beaches (21.7\u0026thinsp;\u0026plusmn;\u0026thinsp;25.9% and 35.9\u0026thinsp;\u0026plusmn;\u0026thinsp;22.0% respectively). However, it was difficult to conclude on any relation between the abundance of fragmented plastic litters and the distance to the sea from our current dataset, because of the lack of sufficient number of sites per river. We observed that abundances of meso- and micro-plastics were the most strongly correlated in both riverbanks and beaches.\u003c/p\u003e \u003cp\u003eNumbers of macro- and microplastics, and meso- and microplastics were positively correlated on both riverbanks and beaches. On beaches, there was a higher correlation between the abundances of meso- and microplastics than between macro- and microplastics (r\u003csub\u003es\u003c/sub\u003e = 0.4, \u003cem\u003ep\u003c/em\u003e-value\u0026thinsp;=\u0026thinsp;6.2 x 10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e; r\u003csub\u003es\u003c/sub\u003e = 0.7, \u003cem\u003ep\u003c/em\u003e-value\u0026thinsp;=\u0026thinsp;7.7 x 10\u003csup\u003e\u0026minus;\u0026thinsp;9\u003c/sup\u003e), which is congruent with previous studies (Lee et al. 2013). The evaluation of the number of mesoplastics was proposed to serve as a better proxy of microplastic pollution than macroplastics, thus helping easier surveys to identify hot spots of microplastic pollution in large geographical areas with limited resources (Lee et al. 2013). That was not the case on riverbanks, where correlations between meso- and microplastics gave the same values than between macro- and microplastics (r\u003csub\u003es\u003c/sub\u003e = 0.51, \u003cem\u003ep\u003c/em\u003e-value\u0026thinsp;=\u0026thinsp;1.1 x 10\u003csup\u003e\u0026minus;\u0026thinsp;5\u003c/sup\u003e for both tests).\u003c/p\u003e \u003cp\u003eMicroplastics represented a major part of the number of plastics found on both riverbanks (47.0\u0026thinsp;\u0026plusmn;\u0026thinsp;34.2% of all plastic debris) and beaches (45.7\u0026thinsp;\u0026plusmn;\u0026thinsp;25.5%). On riverbanks, a large proportion of microplastics were made of polystyrene (43%), which is congruent with previous results showing that such floating plastics tend to beach sooner and accumulate on riverbanks or lake beaches due to wind effects (Corcoran, 2015). On marine beaches, polyethylene dominated the microplastics (61.1%), as classically found in seawaters (Erni-Cassola et al., 2019). Interestingly, we observed on both riverbanks and beaches that a quarter of the microplastics were made of industrial pellets (primary microplastics, also known as virgin pellets or nurdles, recognized by their regular shape, usually cylindrical or ovoid), which form the feedstock of the plastics industry. These pellets enter the environment when they are spilled accidentally, either on land or at sea. Previous observation mentioned the clear link between the presence of industrial pellets and the vicinity to urban-industrial centers or in relation to accidental leakage during transport (Ryan et al., 2018).\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003ePrevious mathematical model based on estimations of river discharge and mismanaged plastic waste resulted in a total global riverine emission of plastics into the ocean in the range of million metric tons per year (Lebreton et al., 2017; Schmidt et al., 2017). A recent study based on in-depth statistical reanalysis of updated data on microplastics demonstrated that current river flux assessments are overestimated by two to three orders of magnitude (Weiss et al., 2021). Such discrepancy demonstrates the need for more field data to improve the modeling estimation to quantify land-based marine debris transport into the ocean. Monitoring all plastics sizes (macro-, meso- and microplastics) both in riverine and marine environments is a prerequisite for understanding how plastic is transported and where it accumulates, as well as how fragmentation occurs. This study presents the power of the \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e initiative that follows the recent recommendation for harmonization of monitoring efforts on riverbanks (Vriend et al., 2020), as previously done for floating macroplastics through the RIMMEL project (Gonz\u0026aacute;lez-Fern\u0026aacute;ndez \u0026amp; Hanke, 2017). Consistent and harmonized sampling and quantification methodologies are required to gather comparable data from the increasing number of scientific and citizen science initiatives around the world. This study presents the first two years data of the \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e initiative in France that is still running for the next coming years with the same protocol and with higher national coverage, both in metropolitan and overseas territorial departments. Schoolchildren removed more than 55,980 pieces of plastic from riverbanks and beaches in two years and prevented the formation of millions of micro- and nanoplastics through degradation over time (Ryan et al., 2020). The increasing number of classes per year (50 in 2019, 150 in 2020, 300 in 2021, 450 in 2022) in the \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e initiative will undoubtedly contribute to the incredibly valuable litter collecting by citizens over the world (European Environment Agency, 2018) and to detect meaningful trends in litter volumes over time on riverbanks and beaches. Engagement went beyond riverbanks or beach clean-ups and instead the \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e initiative was used as a tool to bridge gaps between communities and scientists, while also raising awareness of the plastic pollution, increasing schoolchildren interest for science and inspiring solutions to act.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e-Ethical Approval:\u003c/strong\u003e This article follows the Committee on Publication Ethics (COPE) guidelines, including the ethical responsibilities of authors. The authors declare that they obtained study-specific approval by the appropriate ethics committee for research content of this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-Consent to Participate:\u003c/strong\u003e All authors agreed to participate to the co-authorship. The authors have no competing interests to declare that are relevant to the content of this article.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-Consent to Publish:\u0026nbsp;\u003c/strong\u003eAll co-authors agreed with the content of this article and they all gave explicit consent to submit. They obtained consent from the responsible authorities at the institute/organization where the work has been carried out, before the work has been submitted.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-Author Contributions (CRediT taxonomy): L\u0026eacute;na Philip:\u0026nbsp;\u003c/strong\u003eInvestigation, Methodology, Visualization, Writing - original draft, review \u0026amp; editing; \u003cstrong\u003eMa\u0026euml;la Le Picard\u003c/strong\u003e: Investigation, Methodology, Visualization, Writing - review \u0026amp; editing; \u003cstrong\u003eEdouard Lavergne:\u003c/strong\u003e Investigation, Methodology, Visualization, Writing - review \u0026amp; editing; \u003cstrong\u003ePascaline Bourgain:\u003c/strong\u003e Conceptualization, Project administration, Resources, Supervision, Writing - review \u0026amp; editing; \u003cstrong\u003eBrigitte Sabard:\u003c/strong\u003e Conceptualization, Funding acquisition, Project administration, Resources, Supervision, Writing - review \u0026amp; editing; \u003cstrong\u003eRomain Troubl\u0026eacute;:\u003c/strong\u003e Funding acquisition, Project administration, Supervision, Writing - review \u0026amp; editing; \u003cstrong\u003eAnne-Leila Meistertzheim:\u0026nbsp;\u003c/strong\u003eConceptualization, Funding acquisition, Investigation, Methodology, Supervision, Visualization, Writing - review \u0026amp; editing;\u003cstrong\u003e\u0026nbsp;Wolfgang Ludwig:\u0026nbsp;\u003c/strong\u003eConceptualization, Methodology, Visualization, Writing - review \u0026amp; editing;\u003cstrong\u003e\u0026nbsp;Alexandra ter Halle:\u0026nbsp;\u003c/strong\u003eConceptualization, Methodology, Visualization, Writing - review \u0026amp; editing; \u003cstrong\u003eCamille Lacroix:\u0026nbsp;\u003c/strong\u003eConceptualization, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Visualization, Writing - review \u0026amp; editing;\u003cstrong\u003eJean-Fran\u0026ccedil;ois Ghiglione:\u0026nbsp;\u003c/strong\u003eConceptualization, Funding acquisition, Investigation, Methodology, Project administration, Resources, Supervision, Visualization, Writing - original draft, review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-Funding:\u0026nbsp;\u003c/strong\u003eThis work was supported by the grant PLASTRANSFER supported by the French Agency for Ecological Transition (ADEME) and the French Biodiversity Agency (OFB) and by\u0026nbsp;the European Union\u0026rsquo;s Horizon 2020 research and innovation project AtlantECO under grant agreement No 862923.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-Competing Interests:\u003c/strong\u003e The authors have no relevant financial or non-financial interests to disclose\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e-Availability of data and materials:\u003c/strong\u003e The datasets and materials used and/or analyzed during the current study are available on reasonable request.\u003c/p\u003e\n\u003ch2\u003eAcknowledgments\u003c/h2\u003e \u003cp\u003eWe thank the commitment of the following institutions, persons and sponsors: Agn\u0026egrave;s b., Ademe, Casden, Rothschild Foundation, Philgood foundation and the French Ministry of National Education. We are grateful to Guigui PA, VF, JS, JP for insightful comments on the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAl-Zawaidah, H., Ravazzolo, D., \u0026amp; Friedrich, H. (2021). Macroplastics in rivers : Present knowledge, issues and challenges. \u003cem\u003eEnvironmental Science: Processes \u0026amp; Impacts\u003c/em\u003e, \u003cem\u003e23\u003c/em\u003e(4), 535‑552. https://doi.org/10.1039/D0EM00517G\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAndrady, A. L. (2011). Microplastics in the marine environment. \u003cem\u003eMarine Pollution Bulletin\u003c/em\u003e, \u003cem\u003e62\u003c/em\u003e(8), 1596‑1605. https://doi.org/10.1016/j.marpolbul.2011.05.030\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBarrows, A. P. W., Christiansen, K. S., Bode, E. T., \u0026amp; Hoellein, T. J. (2018). 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The Plastic Cycle \u0026ndash; An Unknown Branch of the Carbon Cycle. \u003cem\u003eFrontiers in Marine Science\u003c/em\u003e, \u003cem\u003e7\u003c/em\u003e. https://www.frontiersin.org/articles/10.3389/fmars.2020.609243\u003c/span\u003e\u003c/li\u003e \u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"environmental-science-and-pollution-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"espr","sideBox":"Learn more about [Environmental Science and Pollution Research](https://www.springer.com/journal/11356)","snPcode":"11356","submissionUrl":"https://submission.nature.com/new-submission/11356/3","title":"Environmental Science and Pollution Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Citizen science, plastic pollution, riverbanks, beaches","lastPublishedDoi":"10.21203/rs.3.rs-3870685/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3870685/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eRivers are the major source of anthropogenic litters entering the ocean, especially plastic debris that accumulate in all ecosystems around the world and pose a risk to the biota. Reliable data on distribution, abundance and types of stranded plastics are needed, especially on riverbanks that have received less attention than beaches. Here, we present the citizen science initiative \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e (Plastic under the magnifier), that compares for the first time the distribution of different litter sizes (macrolitters, meso- and microplastics) over 81 riverbanks and 66 beaches sampled in France between 2019 and 2021. A total of 149 classes (3,113 schoolchildren) from middle class to high school collected, sorted and enumerated 55,986 pieces of plastic to provide a baseline of the current pollution by stranded debris at the national level. Single-use plastics (mainly food-related items) were very abundant on riverbanks (43%), whereas fragmented debris dominated the macrolitter on beaches (28%). Microplastics were always higher in number compared to mesoplastics and macrolitter, with polystyrene and polyethylene found in equivalent proportions on riverbanks while polyethylene dominated microplastics on beaches. Tracing the source of plastic items was possible only for a small proportion of the numerous collected items, mainly for identifiable macrolitter and microplastic pellets. This study lays out the foundations for further works using \u003cem\u003ePlastique \u0026agrave; la loupe\u003c/em\u003e citizen science initiative in France and additional comparisons to other studied habitats worldwide, which can be used by scientists and policy-makers for future litter monitoring, prevention and clean-up strategies.\u003c/p\u003e","manuscriptTitle":"Comparison of the macro-, meso- and microplastic pollution in French riverbanks and beaches using citizen science with schoolchildren","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-14 10:22:12","doi":"10.21203/rs.3.rs-3870685/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revision","date":"2024-05-06T16:55:27+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-02-18T05:23:25+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-02-12T13:41:07+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-01-25T05:13:26+00:00","index":"","fulltext":""},{"type":"submitted","content":"Environmental Science and Pollution Research","date":"2024-01-17T02:33:52+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"environmental-science-and-pollution-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"espr","sideBox":"Learn more about [Environmental Science and Pollution Research](https://www.springer.com/journal/11356)","snPcode":"11356","submissionUrl":"https://submission.nature.com/new-submission/11356/3","title":"Environmental Science and Pollution Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"52182940-c819-4ea4-afd3-6e04f529d9e2","owner":[],"postedDate":"February 14th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-11-18T16:00:44+00:00","versionOfRecord":{"articleIdentity":"rs-3870685","link":"https://doi.org/10.1007/s11356-024-35506-w","journal":{"identity":"environmental-science-and-pollution-research","isVorOnly":false,"title":"Environmental Science and Pollution Research"},"publishedOn":"2024-11-13 15:57:14","publishedOnDateReadable":"November 13th, 2024"},"versionCreatedAt":"2024-02-14 10:22:12","video":"","vorDoi":"10.1007/s11356-024-35506-w","vorDoiUrl":"https://doi.org/10.1007/s11356-024-35506-w","workflowStages":[]},"version":"v1","identity":"rs-3870685","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3870685","identity":"rs-3870685","version":["v1"]},"buildId":"_2-kVJe1T_tPrBINL-cwx","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}