A global snapshot of microplastic contamination in sediments and biota of marine protected areas

Anthropogenic solid waste is ubiquitous in bird nests in coastal multiple use protected areas

Anthropogenic solid residues are a serious environmental issue, affecting both terrestrial and aquatic ecosystems. Birds are particularly vulnerable to waste exposure, as they can interact with it through ingestion, entanglement, or by incorporating residues into their nests. The present study aimed to investigate the occurrence of anthropogenic residues in bird nests and how socio-environmental parameters affect nest anthropogenic contamination within and outside coastal protected areas. The results showed a widespread occurrence of anthropogenic residues in nests of 10 out of 17 bird species studied. Specifically, in nests of Great Kiskadee Pitangus sulphuratus a high contamination frequency (95 %) was verified. In the Generalized Linear Model urbanization levels and vegetation cover assessed using Human Modification Metric (HMc) and the Normalized Difference Vegetation Index (NDVI) did not have statistically significant effects on the presence of anthropogenic residues in bird nests. Similarly, nest location (inside or outside protected areas boundaries) and substrate type (natural or artificial) were not related to contamination level. Therefore, our results suggest that anthropogenic residues are already ubiquitous even within less anthropized areas. Such findings underscore the urgent need for enhanced waste management strategies to mitigate the negative impacts of anthropogenic waste on wildlife and local ecosystems, particularly in protected areas.

Microplastic contamination in no-take Marine Protected Areas of Brazil: Bivalves as sentinels

Microplastics (MPs) are pervasive environmental contaminants even in remote and pristine locations. Despite extensive literature documenting their widespread presence in marine environments, there is limited understanding of MP contamination in Marine Protected Areas (MPAs), particularly in developing countries. This study assessed MP contamination using multiple filter-feeding bivalve species as sentinels. Samplings were performed during 2022, in ten selected no-take MPAs under different management categories according to the International Union for Conservation of Nature. MPs size, shape, color, and polymeric composition were analyzed using established protocols, including Fourier Transform Infrared (FTIR) spectroscopy. MPs concentrations (0.42 ± 0.34 [0.17-2.00] particles.g-1 ww) peaked at natural monuments, while strict nature reserves and parks were less affected. Based on scientific literature comparison, no-take MPAs were less contaminated by MPs than multiple-use MPAs and unprotected areas in Brazil. However, the observed levels remain concerning, given the potential ecological risks, including trophic transfer, physiological disruptions, and habitat degradation. Around 59% of MPs were organic polymers and alkyd (28%), while polyethylene terephthalate (14%) was the main anthropogenic polymer. MPs were predominantly black, white, or transparent fragments measuring <1000 μm, not differing among MPAs individually or grouped protection category, therefore displaying the consistent qualitative patterns along the Brazilian coast. This study underscores the ecological risks posed by MPs in MPAs, emphasizing the need for long-term monitoring programs and targeted mitigation strategies, contributing to global efforts assessing and managing MP contamination, aligning with the 11th Aichi Target to reduce pressures on biodiversity and promote marine ecosystems sustainable use.

Microplastic contamination in wild freshwater fish: Global trends, challenges and perspectives

Microplastics (MPs) are emerging contaminants of global concern with potential risks to wildlife and human health. This study reviewed the literature on MP contamination in wild freshwater fish, analyzing 144 articles published since 2016. Studies were conducted in 45 countries, mainly by China (8.97 %), Bangladesh and India (8.28 % each), and Indonesia (6.90 %). Cypriniformes were the most studied order (52.08 %), with rivers being the predominant sampling sites (57.64 %). Omnivorous fish (80.55 %) were the most studied, and MPs were found in the gastrointestinal tract (51.10 %), gills (19.38 %), and muscle (10.57 %). A total of 450 fish species were found to be contaminated by MPs, including 35 listed on the IUCN Red List: 2 critically endangered, 8 endangered, 12 vulnerable, and 13 near threatened. Although the representativeness of the data may be compromised by selective sampling, polymers such as PE and PP predominated, typically in the form of blue fibers ranging from 0.1 to 0.5 mm, indicating recurring contamination patterns in freshwater environments. Significant research gaps remain, including the need for standardized methods, broader inclusion of Neotropical fish species, investigation of biological responses, and studies on trophic transfer and biomagnification.

Typical migration patterns and fates of microplastics with varying properties in bays and their impacts on coastal ecologically sensitive areas

Rapid urbanization has intensified microplastic pollution in many global bays, yet the mechanisms driving microplastic behavior in these environments remain unclear. This study utilized field surveys, statistical analysis, and modeling methods to address this issue. The findings revealed three typical migration patterns of microplastics in bays. Microplastics less dense than seawater were easily transported by currents, drifting extensively throughout the bay, with about 37.2 % temporarily hovering in tidal channels and low-lying areas, ultimately leaving with ebb tides. Spherical microplastics denser than seawater were predominantly concentrated near the shore, primarily lingering in the subsurface layers. In contrast, fibrous microplastics, which are denser than seawater and the most prevalent type in human-impacted bays, displayed a unique behavior. The combined effects of their density and shape resulted in over 80 % being trapped in intertidal ecologically sensitive areas (ESAs). As a result, local ESAs, such as mangroves, bird habitats, and aquaculture, faced significant threats from fibrous microplastics and their sorption complexes associated with Cu, Pb, Cd, and Hg. Additionally, bay sediments acted as a source-sink community for microplastics. In Shenzhen Bay, China, approximately 27.1 × 1011 microplastic items were buried annually in sediments under normal hydrological conditions. However, if annual rainfall exceeded a threshold, these microplastics could be washed into ocean, serving as a source. Coastal raft aquaculture emerged as a significant contributor to marine microplastics, releasing about 3 %-8 % of terrestrial sources in Shenzhen Bay. This study enhances our understanding of microplastic behaviors and risks in bays.

Assessing microplastic pollution vulnerability in a protected coastal lagoon in the Mediterranean Coast of Egypt using GIS modeling

Lake Burullus is a coastal wetland and protected area on the Mediterranean coast of Egypt. Despite the importance of this lake to the livelihood of millions of Egyptians, intensive anthropogenic activities and drainage water input have impacted its water quality. The current work aimed to evaluate the distribution and composition of microplastics (MPs) in Lake Burullus and analyze the impact of non-point pollution sources on their distribution and fate. The results showed that the average concentration of MPs in the open water was significantly lower (165.0 MPs/m3) than that near the drains (835.6 MPs/m3). The thermal analysis indicated the presence of eight thermoplastic polymers, originating from diffuse sources mainly via land-based activities. Moreover, a model was generated using ArcGIS 10.5 to assess the vulnerability of surface water to pollution from non-point sources. This model incorporated factors such as proximity to roads, waterways, land use, and urban areas, in addition to salinity and total suspended solids (TSS). Comprehensive maps were generated to visually illustrate the areas expected to be affected by MPs pollution. The results showed that waterways played an important role in in the transport of MPs to Lake Burullus. In addition, urban areas were identified as pollution hotspots, indicating the impact of land-use changes in urban areas. Salinity and TSS were also identified as important factors affecting the fate of MPs. Implementing strong measures to control land pollution in urban areas and managing wastewater inputs is highly recommended to effectively mitigate the impact of MPs on the ecosystem of Lake Burullus.

Metagenomic surveys show a widespread diffusion of antibiotic resistance genes in a transect from urbanized to marine protected area

Ports are hot spots of pollution; they receive pollution from land-based sources, marine traffic and port infrastructures. Marine ecosystems of nearby areas can be strongly affected by pollution from port-related activities. Here, we investigated the microbiomes present in sea floor sediments along a transect from the harbour of Livorno (Central Italy) to a nearby marine protected area. Results of 16S rRNA amplicon sequencing and metagenome assembled genomes (MAGs) analyses indicated the presence of different trends of specific bacterial groups (e.g. phyla NB1-j, Acidobacteriota and Desulfobulbales) along the transect, correlating with the measured pollution levels. Human pathogenic bacteria and antibiotic resistance genes (ARGs) were also found. These results demonstrate a pervasive impact of human port activities and highlight the importance of microbiological surveillance of marine sediments, which may constitute a reservoir of ARGs and pathogenic bacteria.

Microplastic in bivalves of an urbanized Brazilian estuary: Human modification, population density and vegetation influence

Microplastics (MPs) global ubiquitously affects particularly coastal regions under significant anthropogenic pressures, where there are limited monitoring efforts. Bivalves are valuable sentinels of MPs contamination. This investigation determined MP contamination in oysters, clams, and mussels at Santos-São Vicente, a heavily urbanized estuary in Brazil, focusing on socio-environmental predictors, spatial distribution, and interspecies variations. Elevated MPs levels were linked to higher human modification (β = 0.5747, p = 0.0223) and reduced population density (β = -8.918e-06, p = 0.0443), regardless of vegetation cover (p > 0.05). Such a negative connection between population density and MP contamination occurred due to the significant presence of industrial and port activities, leading to high MP discharges despite a low population. The simultaneous presence of the three species at specific sites is an intrinsic limitation for broad spatial studies, depending on their environmental availability. Despite higher concentrations in clams, mussels and oysters also exhibited spatial variations in MP concentrations, serving as suitable sentinels. The central and left segments of the estuary displayed elevated MP concentrations, consistent with a well-known contamination gradient. Clams accumulated more MPs (1.97 ± 1.37 [0.00 - 5.55] particles.g-1) than mussels (0.72 ± 1.07 [0.00 - 7.74] particles.g-1) and oysters (0.70 ± 1.03 [0.00 - 7.70] particles.g-1), suggesting higher bioavailability in sediments than the water column. MPs found across all species were predominantly smaller (<1000 µm), fragments or fibers, and colorless. These discoveries lay a groundwork for prospective global investigations by linking MPs concentrations to socio-environmental predictors, contributing to the development of local mitigation measures and global discussions.

Microplastics impair extracellular enzymatic activities and organic matter cycling in oligotrophic sandy marine sediments

Microplastics (MPs) are ubiquitous and constantly accumulating in the marine environment, especially sediments. Yet, it is not well clarified if and how their carbon backbone could interact with surrounding sediments, eventually impairing key benthic processes. We assessed the effects of a 'pulse' contamination event of MPs on sedimentary organic matter (OM) quantity, quality and extracellular enzymatic activities (EEAs), which are well established descriptors of benthic ecosystem functioning. Marine sediments were exposed for 30 days to environmentally relevant concentrations (∼0.2 % in weight) of naturally weathered particles (size range 70-210 μm) of polyurethane, polyethylene, and a mixture of the most common polymers that are documented to accumulate in marine sediments. Despite the low concentration, contaminated sediments showed significantly different composition of OM, showing a decrease in lipid content and increase in protein. Moreover, we document a significant decrease (over 25 %) in quantity of biopolymeric C already after 15 days of exposure, compared to controls. Contaminated sediments showed lower C degradation rates (up to -40 %) and altered EEAs, with alkaline phosphatase being ∼50 % enhanced and aminopeptidase being reduced over 35 % compared to control treatments. Overall, the effects generated by the mixture of polymers were smaller than those exerted by the same amount of a single polymer. Our results provide insights on how that MPs can significantly alter marine sedimentary biogeochemistry through altered benthic processes, that could cumulatively impair whole benthic trophic webs by enhancing the accumulation and possible longer-term storage of recalcitrant organic C in the seabed.

Adsorption and desorption of parachlormetaxylenol by aged microplastics and molecular mechanism

The addition of active ingredients such as antibacterial agent and non-active ingredients such as plastic microspheres (MPs) in personal care products (PCPs) are the common pollutants in the aquatic environment, and their coexistence poses potential threat to the aquatic ecosystem. As a substitute for the traditional antibacterial ingredients triclosan and triclocarban, the usage of parachlormetaxylenol (PCMX) is on the rise and is widely used in PCPs. In this study, the adsorption and desorption behaviors of PCMX were investigated with two typical MPs, polyvinyl chloride (PVC) and polyethylene (PE), and the effects of different aging modes and molecular mechanisms were explored through batch experiments and density functional theory calculation. Both laboratory aging and field aging resulted in surface wrinkles of MPs, along with an increased proportion of oxygen-containing functional groups (CO, -OH). At the same aging time, the degree of laboratory aging was stronger than that of field aging, and the aging degree of PVC was greater that of PE. The aging process enhanced the adsorption capacity of MPs for PCMX. The equilibrium adsorption capacity of PVC increased from 3.713 mg/g (virgin) to 3.823 mg/g (field aging) and 3.969 mg/g (laboratory aging), while that of PE increased from 3.509 mg/g to 3.879 mg/g and 4.109 mg/g, respectively. Meanwhile, aging also resulted in an increase in the desorption capacity of PCMX from PVC and PE. Oxygen-containing functional groups in aged MPs could serve as adsorption sites for PCMX and improved the electrostatic adsorption capacity. Oxygen-containing groups generated on the surface of aged MPs formed hydrogen bonding with the phenolic hydroxyl groups of PCMX, which became the main driving force for adsorption. Our results reveal the potential impact and mechanism of aging on the adsorption of PCMX by MPs, which provides new insights for the interaction mechanism between environmental MPs and associated contaminants.

Microplastics in marine sponges (Porifera) along a highly urbanized estuarine gradient in Santos, Brazil

Microplastics (MPs) are ubiquitously found in environmental matrices, particularly affecting aquatic systems. While several marine species have been widely used to assess MP contamination, sponges (Porifera) are less used. The MPs contamination was assessed in the sun sponge (Hymeniacidon heliophila) along a gradient at the Santos Estuarine System (Brazil). A 14-fold difference between concentrations (particles g-1) was verified between the most (1.40 ± 0.81) and least (0.10 ± 0.12) contaminated sites, confirming the local contamination gradient. The MPs found were primarily polypropylene, small (1.2-1000 μm), fibrous, and colored. Considering total concentrations, sizes and shapes these spatial patterns were similar those previously detected in molluscs obtained in the same sites. On the other hand, they differed in polymeric composition and color categories. Such findings give important initial insights into the potential role of marine sponges as putative sentinels of MPs contamination.

Marine macrolitter and cigarette butts hazard multiple-use marine protected area and fishing community at Brazil

Wide marine litter (ML) contamination impacts human health and economic sectors including fishing, navigation, and tourism. Perequê beach, Brazil, is an authentic fishing community within a touristic multiple-use marine protected area. However, no ML contamination monitoring were so far performed in the region. This study evaluated the spatiotemporal abundance, composition, sources, and associated ML hazards at Perequê beach using a multi-index approach. The 2579 items (0.64 ± 0.72 items.m-2) yielded a high contamination level (CCI = 12.6 ± 14.4) with plastic (44.6-50.9 %) and cigarette butts (20.6-28.4 %) prevalence, while primary sources were smoking (cigarette butts, lighters, others-21.2-30.1 %) and packaging (17.8-22.8 %). Levels of pollutants leaked from cigarette butts (CBPI = 30.5 ± 47.5) and hazardous items (HALI = 3.06 ± 2.64) were among the highest globally. Heightened levels occurred in summer, at dry sand strip, where short-term buoyant items prevailed. Multi-indexing approaches offer valuable insights for local authorities to implement mitigation programs, while contributing to global discussions, promoting awareness, and facilitating replicability.

Impacts of microplastics on ecosystem services and their microbial degradation: a systematic review of the recent state of the art and future prospects

Microplastics are tiny plastic particles with a usual diameter ranging from ~ 1 μ to 5 µm. Recently, microplastic pollution has raised the attention of the worldwide environmental and human concerns. In human beings, digestive system illness, respiratory system disorders, sleep disturbances, obesity, diabetes, and even cancer have been reported after microplastic exposure either through food, air, or skin. Similarly, microplastics are also having negative impacts on the plant health, soil microorganisms, aquatic lives, and other animals. Policies and initiatives have already been in the pipeline to address this problem to deal with microplastic pollution. However, many obstacles are also being observed such as lack of knowledge, lack of research, and also absence of regulatory frameworks. This article has covered the distribution of microplastics in water, soil, food and air. Application of multimodel strategies including fewer plastic item consumption, developing low-cost novel technologies using microorganisms, biofilm, and genetic modified microorganisms has been used to reduce microplastics from the environment. Researchers, academician, policy-makers, and environmentalists should work jointly to cope up with microplastic contamination and their effect on the ecosystem as a whole which can be reduced in the coming years and also to make earth clean.

Dynamics and functions of microbial communities in the plastisphere in temperate coastal environments

Microbial attachment and biofilm formation on microplastics (MPs <5 mm in size) in the environment have received growing attention. However, there is limited knowledge of microbial function and their effect on the properties and behavior of MPs in the environment. In this study, microbial communities in the plastisphere were explored to understand microbial ecology as well as their impact on aquatic ecosystems. Using the amplicon sequencing of 16S and internal transcribed spacer (ITS) genes, we uncovered the composition and diversity of bacterial and fungal communities in samples of MPs (fiber, film, foam, and fragment), surface water, bottom sediment, and coastal sand in two contrasting coastal areas of Japan. Differences in microbial diversity and taxonomic composition were detected depending on sample type (MPs, water, sediment, and sand) and the research site. Although relatively higher bacterial and fungal gene counts were determined in MP fragments and foams from the research sites, there were no significant differences in microbial community composition depending on the morphotypes of MPs. Given the colonization by hydrocarbon-degrading communities and the presence of pathogens on MPs, the complex processes of microbial taxa influence the characteristics of MP-associated biofilms, and thus, the properties of MPs. This study highlights the metabolic functions of microbes in MP-associated biofilms, which could be key to uncovering the true impact of plastic debris on the global ecosystem.

Mass concentration of plastic particles from two-dimensional images

Imaging techniques play a crucial role in characterizing environmental plastics. However, most reported findings rely on two-dimensional projections of particles resting on flat surfaces. This limitation makes it challenging to accurately determine mass concentration, which is essential for deriving toxicologically relevant exposure data. The primary issue arises from the loss of information regarding particle height or thickness. This study aims to evaluate the assumptions necessary to compensate this loss of information. To achieve this, we used a set of environmental plastic particles, mesoplastics and microplastics, from marine campaigns, and precisely measured their three spatial dimensions and mass. Our study demonstrated the feasibility of estimating the mass of plastic particles through two-dimensional images. However, for enhanced accuracy, additional information derived from the dataset of particles under examination is necessary. Specifically, estimating the mass of platelike particles requires information about their height. Similarly, calculating the volume for elongated shapes as cylinders, should be limited to particles with the same width and height and for which their length can be precisely determined, even if the image depicts twisted forms. In conclusion, while obtaining mass concentration from single two-dimensional images enables reasonable estimations, achieving the precision needed for exposure data requires acquiring additional information from the sample and carefully considering the shape of each individual particle.

Microplastic contamination in three environmental compartments of a coastal lagoon in the southern Gulf of Mexico

The Sontecomapan lagoon (Mexico) is a Ramsar site within the Los Tuxtlas Biosphere Reserve, facing the Gulf of Mexico. Although the site has a protected area status, it is vulnerable to microplastic contamination, whose long-term effects are uncertain. This study gives the first approach to the degree of contamination by microplastics in surface waters, zooplankton, and sediments in the lagoon. The samples in these three environmental compartments were collected in June 2018 and analyzed in the laboratory to extract and quantify the microplastics. The microplastics sampled were classified into fibers, fragments, and foams and identified as polyester, acrylic, and rayon, among others. In the surface waters, the mean concentration of microplastics was 7.5 ± 5.3 items/L, which is higher than the values registered in other protected coastal systems, perhaps because of differences in the methods used. Zooplankton, represented by copepods, luciferids, and chaetognaths, showed concentrations of 0.002 ± 0.005, 0.011 ± 0.011, and 0.019 ± 0.016 items/individual, respectively. These values were low compared to systems with high anthropic influence, and the differences between the three kinds of organisms were attributed to their feeding habits. In the sediments, the mean concentration was 8.5 ± 12.5 items/kg, lower than the values registered in sites of high human impact; the maximum value here found (43 items/kg) was recorded in the internal part of a lagoon arm of almost stagnant water. In general, the degree of contamination by microplastics in the lagoon was low; however, their presence indicates a potential risk to the biota.

Low prevalence of microplastic contamination in the bottom sediments and deep-sea waters of the Bransfield strait, Antarctica

Despite the remoteness of the Antarctic continent and Southern Ocean, microplastic (MPs) contamination has been evidenced in recent years. However, the deep-sea compartments of the Southern Ocean are yet to be investigated. In the present study, we conducted a baseline MP assessment of the deep-sea waters and bottom sediments of the Bransfield Strait, Antarctica. A low abundance of suspected MPs was found. The average MP abundances in bottom sediments and water samples were 0.09 MP/g (range of 0-0.2 MP/g) and 7.00 MP/L (range of 0-16 MP/L), respectively. The majority of the particles were fibers identified as cellulose, although polyethylene terephthalate (PET) and polyacrylonitrile (PAN) was also detected. These results suggest low MP contamination levels in the Southern Ocean's deepest environmental compartments. However, future studies must aim to investigate the smallest MP fractions and, if possible, nanoplastic (<1 μm) contamination in these remote compartments.

Comprehensive risk assessment of microplastics in tidal channel sediments in amazonian mangroves (northern Brazil)

Pollution by microplastics (MPs) in mangroves is a growing concern, given its potential ecological and human health impacts. The characteristics of microplastic pollution and a risk assessment of MPs in the Amazon region's coastal sediments are still insufficient, and information about MP pollution in the benthic component of the mangrove ecosystem is lacking. We analyzed MP concentrations in the surface sediment of 9 stations in three tidal channels along the Ajuruteua Peninsula connected to the Caeté River estuary, aiming to assess the hazard level on the environment based on the Pollution Load Index (PLI). Raman and Fourier transform infrared spectroscopy determined the MP's chemical composition. The results showed that the abundance of sediment MPs ranged from 100 to 1200 items kg-1, with an average of 433 ± 261.6 items kg-1. The MPs were mainly composed of transparent and blue fragments and fibers, ranging in size from 100 to 5000 μm. Six types of polymers were identified, including alkyd varnish (AV), resin dispersion (RD), chlorinated polyethylene (CPE), polyethylene-polypropylene (PE-PP), low-density polyethylene (LDPE), and hostaperm blue (HB). Hydrodynamic processes within estuaries and tidal channels play a crucial role in explaining the concentrations found, as circulation determines the pattern of sediment deposition and the particles adhered to it. PLI risk assessment showed that all sampling sites were at hazard level I: a low level of contamination in the mangrove sediments. However, a more comprehensive and systematic monitoring campaign is needed to expand our knowledge about pollution and contamination by MPs in Amazon mangrove areas.

Chemical contamination affecting filter-feeding bivalves in no-take marine protected areas from Brazil

Marine protected areas (MPAs) are zones geographically delimited under pre-defined management goals, seeking to reduce anthropogenic threats to biodiversity. Despite this, in recent years reports of MPAs affected by chemical contamination has grown. Therefore, this study addresses this critical issue assessing legacy and current chemical contamination in filter-feeder bivalves obtained in very restrictive no-take MPAs from Brazil. The detected pollutants encompass polycyclic aromatic hydrocarbons (PAHs), linear alkylbenzenes (LABs), and persistent organic pollutants (POPs) like dichlorodiphenyltrichloroethane (DDTs) and polychlorinated biphenyls (PCBs). Despite protective measures, bivalves from nine MPAs exhibited high LABs (13.2-1139.0 ng g-1) and DDTs levels (0.1-62.3 ng g-1). PAHs were present in low concentrations (3.1-29.03 ng g-1), as PCBs (0.7-6.4 ng g-1), hexachlorobenzene (0.1-0.2 ng g-1), and Mirex (0.1-0.3 ng g-1). Regardless of the sentinel species, MPAs and management categories, similar accumulation patterns were observed for LABs, DDTs, PAHs, and PCBs. Based on the limits proposed by Oslo Paris Commission, the measured levels of PAHs, PCBs and were below the environmental assessment criteria. Such findings indicate the no biological effects are expected to occur. However, they are higher considering background conditions typically measured in remote or pristine areas and potential simultaneous exposure. Such findings indicate an influence of anthropogenic sources, emphasizing the urgency for monitoring programs guiding strategic management efforts to safeguard these areas.

Terrestrial wildlife as indicators of microplastic pollution in western Thailand

Plastic pollution in terrestrial wildlife represents a new conservation challenge, with research in this area, especially within protected areas (PAs), being scant. This study documents the accumulation of microplastics (MPs) in terrestrial wildlife both inside and outside PAs in western Thailand. Carcasses of road-killed vertebrates in good condition, as well as live tadpoles, were collected to examine their exposure to plastic pollution. The digestive tracts of the vertebrate carcasses and the entire bodies of tadpoles were analyzed for MPs, which were identified if they measured over 50 µm. A total of 136 individuals from 48 vertebrate species were examined. The sample comprised snakes (44.12%), birds (11.03%), lizards (5.15%), tadpoles (32.25%), amphibians (5.88%), and mammals (1.47%). In total, 387 MPs were found in 44 species (91.67%), with an average occurrence of 3.25 ± 3.63 MPs per individual or 0.05 ± 0.08 MPs per gram of body weight. The quantities of MPs significantly varied among the animal groups, both in terms of number per individual (p < 0.05) and number per gram of body weight (p < 0.01). Furthermore, a significant difference in MP quantities was observed between specimens collected inside and outside PAs on an individual basis (p < 0.05), but not on a body weight basis (p = 0.07). Most MPs were fibers (77%), followed by fragments (22.22%), with only a minimal presence of film (0.52%) and foam (0.26%). Of all the MPs identified, 36.84% were confirmed as plastics or fibers made from natural materials, and 31.58% were plastics, including Polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), Polyvinylidene chloride (PVDC), and polyester (PES). Additionally, fibers made of cotton, and those containing polyurethane (PU), rayon, PES, and combinations of rayon and PU, were identified. The quantities of MPs were significantly influenced by animal body weight, factors associated with human settlement/activity, and land use types. Our findings highlight the prevalence of plastic pollution in terrestrial vertebrates within Thai PAs. Further toxicological studies are required to establish plastic pollution standards. It is proposed that snakes, obtained from road kills, could serve as a non-invasive method for monitoring plastic pollution, thus acting as an indicator of the pollution threat to species within terrestrial ecosystems. There is an urgent need for the standardization of solid waste management at garbage dump sites in remote areas, especially within PAs. Conservation education focusing on MP occurrence, potential sources, and impacts could enhance awareness, thereby influencing changes in behaviors and attitudes toward plastic waste management at the household level.

Microplastics in rocky shore mollusks of different feeding habits: An assessment of sentinel performance

Microplastics (MPs) accumulation in rocky shore organisms has limited knowledge. This study investigated MPs accumulation in filter-feeding oysters, herbivorous limpets and carnivorous snails to assess their performance as sentinel species in the MPs trophic transfer. The samples were obtained along a contamination gradient in the Santos Estuarine System, Brazil. All three studied species showed MPs concentrations related to the contamination gradient, being the oysters the species that showed the highest levels, followed by limpets and snails (average of less and most contaminated sites of 1.06-8.90, 2.28-5.69 and 0.44-2.10 MP g-1, respectively), suggesting that MPs ingestion rates are linked to feeding habits. MPs were mainly polystyrene and polyacetal. The polymer types did not vary among sites nor species. Despite minor differences in percentages and diversity of size, shape, and color classes, the analyzed species were equally able to demonstrate dominance of small, fiber, transparent, black and blue MPs. Thus, oysters, limpets, and snails are proposed as sentinels of MPs in monitoring assessments.

Microplastic in clams: An extensive spatial assessment in south Brazil

Microplastic pollution is becoming a continuously growing environmental concern, while bivalve mollusks are particularly vulnerable due to their sessile habits and feeding through water filtration processes. Microplastic incidence in soft tissues of the clam Amarilladesma mactroides was assessed along unconsolidated substrates distributed in extensive coastal regions of southern Brazil. Influence of urbanization levels, distance to rivers and local hydrodynamics on microplastic accumulation by the clam was tested. The average concentration of microplastics was high (3.09 ± 2.11 particles.g-1), considering 16 sampled sites. Particles were mainly composed by polyamide, polyethylene and polyethylene terephthalate, while were mainly smaller, fibrous and colorless. High urbanization and closer proximity to rivers insured higher contamination, which is a trend observed globally. No influence of coastal hydrodynamics was seen. Considering obtained findings, A. mactroides presents good potential to be used as a valuable tool to assess microplastic contamination in unconsolidated substrates of beach areas.

Azoic sediments and benthic foraminifera: Environmental quality in a subtropical coastal lagoon in the gulf of California

Marine transitional environments play an important role in human sustainability. Around these ecosystems, coastal lagoons are subject to high anthropogenic pressure from population growth. The increased demand for goods and services is associated with the elevated discharge of untreated and treated wastewater into lagoon systems. The absence of benthic organisms in lagoon environments has been linked to extreme natural conditions and severe anthropogenic impact at both spatial and temporal scales. However, the mechanisms that lead to the presence of azoic sediments in lagoon environments have yet to be studied. This study aimed to determine the vertical variability of textural groups, geochemistry, and benthic foraminiferal fauna to understand how natural and anthropogenic components generate a vertical sediment sequence with low or absent benthic foraminifera in a subtropical coastal lagoon in the southwestern end of the Gulf of California. A 41 cm-long sediment core was collected from La Paz Lagoon at a 1-m depth. The core was sectioned every centimeter, and sediment subsamples were dried and homogenized for grain size, calcium carbonate, elemental and isotopic carbon and nitrogen analyses, and benthic foraminifera quantification. Muds with fine sands towards the core's base characterized the sedimentary sequence. Organic carbon and total nitrogen increased from the base (1.4% and 0.06%, respectively) to the core-top (CT, 3.0% and 0.14%, respectively), significant from the 27 cm interval. Calcium carbonate content was very low (<0.8%). The relationship of δ13C vs. C:N ratio indicated that sedimentary organic carbon was derived from the marine and sewage source mixture. The δ15N of organic matter increased by 3.7‰, starting from the 27 cm interval towards the CT. The nitrogen sewage input source was relatively more significant than nitrogen fixation. The few individuals (<18 ind. in 10 g) and genera (Ammonia and Elphidium), as well as the absence of foraminifera in 19 of 41 intervals in the core, indicated that environmental conditions were unfavorable, even for colonization of environmentally stress-tolerant genera. The frequency of azoic sediments was higher from the 25 cm interval to the CT vs. from the base to the 25 cm interval. Moreover, the AEI revealed severe to moderate hypoxia in the study area. The limited presence of benthic foraminifera and calcium carbonate preservation corroborated that the quality of the lagoon's environment has deteriorated along with population growth, which requires strategic programs to sustain this transitional ecosystem.

Insight into microplastics in the aquatic ecosystem: Properties, sources, threats and mitigation strategies

Globally recognized as emergent contaminants, microplastics (MPs) are prevalent in aquaculture habitats and subject to intense management. Aquaculture systems are at risk of microplastic contamination due to various channels, which worsens the worldwide microplastic pollution problem. Organic contaminants in the environment can be absorbed by and interact with microplastic, increasing their toxicity and making treatment more challenging. There are two primary sources of microplastics: (1) the direct release of primary microplastics and (2) the fragmentation of plastic materials resulting in secondary microplastics. Freshwater, atmospheric and marine environments are also responsible for the successful migration of microplastics. Until now, microplastic pollution and its effects on aquaculture habitats remain insufficient. This article aims to provide a comprehensive review of the impact of microplastics on aquatic ecosystems. It highlights the sources and distribution of microplastics, their physical and chemical properties, and the potential ecological consequences they pose to marine and freshwater environments. The paper also examines the current scientific knowledge on the mechanisms by which microplastics affect aquatic organisms and ecosystems. By synthesizing existing research, this review underscores the urgent need for effective mitigation strategies and further investigation to safeguard the health and sustainability of aquatic ecosystems.

Psychrobacter species enrichment as potential microplastic degrader and the putative biodegradation mechanism in Shenzhen Bay sediment, China

Microplastic (MP) pollution has emerged as a pressing environmental concern due to its ubiquity and longevity. Biodegradation of MPs has garnered significant attention in combatting global MP contamination. This study focused on MPs within sediments near the sewage outlet of Shenzhen Bay. The objective was to elucidate the microbial communities in sediments with varying MPs, particularly those with high MP loads, and to identify microorganisms associated with MP degradation. The results revealed varying MP abundance, ranging from 211 to 4140 items kg-1 dry weight (d. w.), with the highest concentration observed near the outfall. Metagenomic analysis confirmed the enrichment of Psychrobacter species in sediments with high MP content. Psychrobacter accounted for ∼16.71% of the total bacterial community and 41.71% of hydrocarbon degrading bacteria at the S3 site, exhibiting a higher abundance than at other sampling sites. Psychrobacter contributed significantly to bacterial function at S3, as evidenced by the Kyoto Encyclopedia of Genes and Genomes pathway and enzyme analysis. Notably, 28 enzymes involved in MP biodegradation were identified, predominantly comprising oxidoreductases, hydrolases, transferases, ligases, lyases, and isomerases. We propose a putative mechanism for MP biodegradation, involving the breakdown of long-chain plastic polymers and subsequent oxidation of short-chain oligomers, ultimately leading to thorough mineralization.

Abundance and characterization of microplastic pollution in the wildlife reserve, Ramsar site, recreational areas, and national park in northern Jakarta and Kepulauan Seribu, Indonesia

This is the first study to evaluate the presence and distribution of microplastics in sediments in the regions with a unique degree of complexity, such as wildlife reserve areas, a Ramsar site that connects directly to Greater Jakarta's mainland, recreational islands, and a marine national park. Microplastics of varying sizes and shapes are found in all places, with an increase trend in the abundance toward areas near to the epicenter of human activity. Comparatively to other marine protected areas, the amount of microplastics discovered is comparable; however, there is an upward trend. Season influences microplastic accumulation, with the dry season causing the greater accumulation. Small-sized microplastics and microplastics resulting from large plastic fragments were predominantly discovered. The properties of microplastics in the study region are dominated by polyethylene, polypropylene, polystyrene, polyvinyl chloride, and nylon. Additional in-depth research and waste reduction from all sources that involve all stakeholders are required to reduce the amount of contaminants entering the protected area.

The path of microplastics through the rare biodiversity estuary region of the northern Bay of Bengal

Due to its harmful effects on ecosystems and human health, microplastic (MP) pollution has become a significant environmental problem on a global scale. Although MPs' pollution path and toxic effects on marine habitats have been examined worldwide, the studies are limited to the rare biodiversity estuary region of Hatiya Island from the northern Bay of Bengal. This study aimed to investigate the MP pollution path and its influencing factors in estuarine sediments and water in rare biodiversity Hatiya Island in the northern Bay of Bengal. Sixty water and sediment samples were collected from 10 sampling sites on the Island and analyzed for MPs. The abundance of MPs in sediment ranged from 67 to 143 pieces/kg, while the abundance in water ranged from 24.34 to 59 pieces/m3. The average concentrations of MPs in sediment and water were 110.90 ± 20.62 pieces/kg and 38.77 ± 10.09 pieces/m3, respectively. Most identified MPs from sediment samples were transparent (51%), while about 54.1% of the identified MPs from water samples were colored. The fragment was the most common form of MP in both compartments, with a value of 64.6% in sediment samples and 60.6% in water samples. In sediment and water samples, almost 74% and 80% of MP were <0.5 mm, respectively. Polypropylene (PP) was the most abundant polymer type, accounting for 51% of all identified polymers. The contamination factor, pollution load index, polymer risk score, and pollution risk score values indicated that the study area was moderately polluted with MPs. The spatial distribution patterns and hotspots of MPs echoed profound human pathways. Based on the results, sustainable management strategies and intervention measures were proposed to reduce the pollution level in the ecologically diverse area. This study provides important insights into evaluating estuary ecosystem susceptibility and mitigation policies against persistent MP issues.

Quantifying microplastics pollution in the Red Sea and Gulfs of Suez and Aqaba: Insights from chemical analysis and pollution load assessment

Microplastics (MPs) constitute the majority of marine plastic litter. The pollution caused by MPs has been categorized as a gradual and persistent crisis, but little is known about its extent along the shores of the Red Sea, particularly on the Egyptian side. The Red Sea is a rapidly developing region and home to critical ecosystems with high levels of endemism. This study represents the first comprehensive survey investigating the extent of MP pollution along the Egyptian shores of the Red Sea, including the Gulf of Suez and Aqaba. Mean concentrations ranged from 23.3 ± 15.28 to 930.0 ± 181.9 MPs/kg DW. Out of 17 beaches surveyed, 12 had mean concentrations of <200 items/kg, indicating a low occurrence of MPs compared to the shores of the Mediterranean Coast of Egypt. The pollution load index varied from low to medium levels in most locations. Ras Mohamed, a marine protected area, showed high vulnerability to MP pollution. All the investigated particles were fragments of secondary MPs. The sources of pollution mainly come from maritime activities, including cargo shipping and intense recreational activities. Fourier Transform Infrared Spectroscopy identified four plastic polymers, with polyethylene and polypropylene being the most common. The surface morphology of plastic particles was examined using scanning electron microscopy combined with energy-dispersive X-ray spectroscopy. All the particles exhibited signs of degradation, which could generate countless plastic pieces with possible deleterious impacts. This work has highlighted the importance of conducting region-specific assessments of mismanaged plastic waste, focusing on the role of tourism and recreational navigation as contributors to plastic litter, to estimate plastic waste inputs into the waters of the Red Sea Coast of Egypt. Efforts are needed to develop strategic plans to reduce the disposal of plastic waste in the region.

Plastic and paint debris in marine protected areas of Peru

Contamination with anthropogenic debris, such as plastic and paint particles, has been widely investigated in the global marine environment. However, there is a lack of information regarding their presence in marine protected areas (MPAs). In the present study, the abundance, distribution, and chemical characteristics of microplastics (MPs; <5 mm), mesoplastics (MePs; 5-25 mm), and paint particles were investigated in multiple environmental compartments of two MPAs from Peru. The characteristics of MPs across surface water, bottom sediments, and fish guts were similar, primarily dominated by blue fibers. On the other hand, MePs and large MPs (1-5 mm) were similar across sandy beaches. Several particles were composite materials consisting of multiple layers confirmed as alkyd resins by Fourier-transformed infrared spectroscopy, which were typical indicators of marine coatings. The microstructure of paint particles showed differentiated topography across layers, as well as different elemental compositions. Some layers displayed amorphous structures with Ba-, Cr-, and Ti-based additives. However, the leaching and impact of potentially toxic additives in paint particles require further investigation. The accumulation of multiple types of plastic and paint debris in MPAs could pose a threat to conservation goals. The current study contributed to the knowledge regarding anthropogenic debris contamination in MPAs and further elucidated the physical and chemical properties of paint particles in marine environments. While paint particles may look similar to MPs and MePs, more attention should be given to these contaminants in places where intense maritime activity takes place.

Plastisphere characterization in habitat of the highly endangered Shinisaurus crocodilurus: Bacterial composition, assembly, function and the comparison with surrounding environment

Plastisphere is a new niche for microorganisms that complicate the ecological effects of plastics, and may profoundly influence biodiversity and habitat conservation. The DaGuishan National Nature Reserve, one of the largest habitats of the highly endangered crocodile lizard (Shinisaurus crocodilurus), is experiencing plastic pollution without sufficient attention. Here, plastisphere collected from captive tanks of crocodile lizards in this nature reserve was characterized for the first time. Three types of plastic (PE-PP, PE1, and PE2) together with the surrounding water and soil samples, were collected, and 16S rRNA sequencing technology was used to characterize the bacterial composition. The results demonstrated that plastisphere was driven by stochastic process and had a distinct bacterial community with higher diversity than that in surrounding water (p < 0.05). Bacteria related to nitrogen and carbon cycles (Pseudomonas psychrotolerans, Methylobacterium-Methylorubrum) were more abundant in plastisphere than in water or soil (p < 0.05). More importantly, plastics recruited pathogens and those bacteria function in antibiotic resistant genes (ARGs) coding. Bacteria related to polymer degradation also proliferated in plastisphere, especially Bacillus subtilis with a fold change of 42.01. The PE2 plastisphere, which had the lowest diversity and was dominated by Methylobacterium-Methylorubrum differed from PE 1 and PE-PP plastispheres totally. Plastics' morphology and aquatic nutrient levels contributed to the heterogeneity of different plastispheres. Overall, this study demonstrated that plastispheres diversify in composition and function, affecting ecosystem services directly or indirectly. Pathogens and bacteria related to ARGs expression enriched in the plastisphere should not be ignored because they may threaten the health of crocodile lizards by increasing the risk of infection. Plastic pollution control should be included in conservation efforts for crocodile lizards. This study provides new insights into the potential impacts of plastisphere, which is important for ecological risk assessments of plastic pollution in the habitats of endangered species.

Unveiling the hidden threat of microplastics to coral reefs in remote South Atlantic islands

The widespread presence of marine microplastics (< 5 mm) is a significant concern, as it may harm marine biodiversity and ocean ecosystems. Corals' capacity to ingest microplastics has emerged as a significant threat to reef ecosystems, owing to the detrimental physiological and ecological effects it can trigger. The extent of the impact of microplastics on Brazilian corals remains unclear and this study aimed to investigate its distribution and characteristics in four coral species: Favia gravida, Mussismilia hispida, Montastrea cavernosa, and Siderastrea stellata, found in the Trindade and Martim Vaz Islands - the most isolated archipelago of Brazil, located about 1200 km (680 miles) east of the coast. This study aims to reveal the extent of microplastic distribution in the coral reef environment, assess the amount of microplastics in different coral species, and compare each species' capacity to adhere and accumulate microplastics. A high concentration of ingested and adhered microplastics was detected in all coral species evaluated in the present study. No significant differences were observed in the sampling points which indicates that although the sampling points are located at different distances from the coast, the microplastic pollution is equally distributed in the region. Polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), poly(methyl methacrylate) (PMMA), Rayon, and Nylon particles were detected, with a predominance of PE (45.5 %). No significant differences in microplastic concentration were detected among the various species and locations studied. Our research presents findings that demonstrate the extensive occurrence of microplastic contamination in coral colonies located on remote islands.

Microplastics in aquaculture systems: Occurrence, ecological threats and control strategies

With the intensification of microplastic pollution globally, aquaculture environments also face risks of microplastic contamination through various pathways such as plastic fishing gear. Compared to wild aquatic products, cultured aquatic products are more susceptible to microplastic exposure through fishing tackle, thus assessing the impacts of microplastics on farmed species and human health. However, current research on microplastic pollution and its ecological effects in aquaculture environments still remains insufficient. This article comprehensively summarizes the pollution characteristics and interrelationships of microplastics in aquaculture environments. We analyzed the influence of microplastics on the sustainable development of the aquaculture industry. Then, the potential hazards of microplastics on pond ecosystems and consumer health were elucidated. The strategies for removing microplastics in aquaculture environments are also discussed. Finally, an outlook on the current challenge and the promising opportunities in this area was proposed. This review aims to evaluate the value of assessing microplastic pollution in aquaculture environments and provide guidance for the sustainable development of the aquaculture industry.

Bibliometric review on microplastic contamination in the Pacific Alliance countries

Microplastics, capable of absorbing persistent organic compounds, heavy metals, and emerging pollutants, are of global concern due to their potential to alter the behavior and metabolism of biota. In Latin America, the Pacific Alliance, comprising Mexico, Colombia, Peru, and Chile, stands out for its biological wealth and productive ecosystems, which account for 37% of the region's gross domestic product. The leaders of these countries expressed their concern about microplastic pollution and pledged to take joint action. We conducted an analysis of the scientific production of these countries and the collaborations of their researchers, focused on the period 2015-2023, using Scopus and SCImago. We observed that marine-coastal/wetland ecosystems are the most studied, with a focus on fish, and that Mexico leads in publications, followed by Colombia, Peru, and Chile. In addition, we note the absence of an inter-institutional group dedicated to microplastics research in these countries. We recommend promoting collaboration between academic institutions specialized in microplastic research and government agencies dedicated to the promotion of science and technology in the countries belonging to the Pacific Alliance.

Impact and mitigation of lead, cadmium and micro/nano plastics in fragrant rice

Heavy metals (HMs) and micro(nano)plastics (MNPs), represent a significant risk to global food supply as well as a potential risk to humankind. Over 50% of the worldwide population eat rice every day, and rice aroma is a significant qualitative trait that is highly valued by consumers and fetches premium prices in the global market. Despite the huge commercial importance of fragrant rice, limited studies were directed to investigate the influence of HMs and MNPs on yield related traits and 2-Acetyl-1-pyrroline (2-AP) compound, mainly responsible for aroma production in fragrant rice. In this review, we found that the interaction of HMs and MNPs in fragrant rice is complex and accumulation of HMs and MNPs was higher in root as compared to the grains. Nutrients and phytohormones mediated mitigation of HMs and MNPs were most effective sustainable strategies. In addition, monitoring the checkpoints of 2-AP biosynthesis and its interaction with HMs and MNPs is challenging. Finally, we explained the potential challenges that fragrant rice faces considering the continuous rise in environmental pollutants and discussed the future avenues of research to improve fragrant rice's yield and qualitative traits.

The impact of microplastics on bivalve mollusks: A bibliometric and scientific review

Bivalves are important members of the ecosystem and their populations are declining globally, making them a concern for their role in ecosystem services and the fishing industry. Bivalves are excellent bioindicators of MPs pollution due to their widespread distribution, filtering capabilities, and close association with human health. Microplastics (MPs) have direct and indirect impacts on bivalves, affecting their physiology, habitat structure, food sources, and persistence of organic pollutants. This review provides an extensive overview of the impact of MPs on bivalves, covering various aspects such as their economic significance, ecological roles, and importance in biomonitoring environmental quality. The article presents the current state of knowledge on the sources and pathways of MPs in aquatic environments and their effects on bivalves. The mechanisms underlying the effects of MPs on bivalves, including ingestion, filtration activity, feeding inhibition, accumulation, bioaccumulation, and reproduction, are also discussed. Additionally, a bibliometric analysis of research on MPs in bivalves is presented, highlighting the number of papers, geographical distribution, and keyword clusters relating to MPs. Finally, the review emphasizes the importance of ongoing research and the development of mitigation strategies to reduce the negative effects of MPs pollution on bivalves and their habitats in oceans and coastal waters.

Release characteristics and toxicity assessment of micro/nanoplastics from food-grade nonwoven bags

Micro/nanoplastic (M/NP) contamination in food has become a global concern. Food-grade polypropylene (PP) nonwoven bags, which are widely used to filter food residues, are considered environmentally friendly and nontoxic. However, the emergence of M/NPs has forced us to re-examine the use of nonwoven bags in cooking as plastic contact with hot water leads to M/NP release. To evaluate the release characteristics of M/NPs, three food-grade PP nonwoven bags of different sizes were boiled in 500 mL water for 1 h. Micro-Fourier transform infrared spectroscopy and Raman spectrometer confirmed that the leachates were released from the nonwoven bags. After boiling once, a food-grade nonwoven bag can release 0.12-0.33 million MPs (>1 μm) and 17.6-30.6 billion NPs (<1 μm), equivalent to a mass of 2.25 - 6.47 mg. Number of M/NPs released is independent of nonwoven bag size; however, it decreases with increasing cooking times. M/NPs are primarily produced from easily breakable PP fibers, and they are not released into the water at once. Adult zebrafish (Danio rerio) were cultured in filtered distilled water without released M/NPs and in water containing 14.4 ± 0.8 mg L^-1 released M/NPs for 2 and 14 days, respectively. To evaluate the toxicity of the released M/NPs on the gills and liver of zebrafish, several oxidative stress biomarkers (i.e., reactive oxygen species, glutathione, superoxide dismutase, catalase, and malonaldehyde) were measured. The ingestion of the released M/NPs by zebrafish induces oxidative stress in the gills and liver, depending on the exposure time. Food-grade plastics, such as nonwoven bags, should be used with caution in daily cooking because they release large amounts of M/NPs when heated, which can threaten human health.

Seasonal distribution of microplastics in the surface waters of the Yellow Sea, China

Different studies are filling the gaps in the distribution map of global marine microplastics. However, the data on the seasonal variation is relatively limited, which may lead to overestimation or underestimation of the distribution level of microplastics. To understand baseline data and seasonal variations of the microplastics in the surface seawater of the Yellow Sea, a survey over four seasons was conducted during 2017-2018. Microplastics were collected using a 330 μm manta net. It was found that the abundance of microplastics was 0.63 ± 0.57 particles/m³. The seasonal abundance variation was spring > summer ≈ winter > autumn. The main categories were foam, line, and fragments, accounting for 32 %, 19 %, and 19 % of the total amount, respectively, and the dominant components were polypropylene, polyethylene, and polyethylene terephthalate, accounting for 38 %, 22 %, and 22 % of particles, respectively. The factors affecting the variation included wind-induced mixing, river input, and environmental topography.

The octopus pot on the North Atlantic Iberian coast: A plague of plastic on beaches and dunes

This baseline focuses on the octopus pot, a litter item found on the North Atlantic Iberian coast. Octopus pots are deployed from vessels in ropes, with several hundred units, and placed on the seabed, to capture mostly Octopus Vulgaris. The loss of gears due to extreme seas state, bad weather and/or fishing-related unforeseen circumstances, cause the octopus pots contaminating beaches and dunes, where they are transported by sea current, waves and wind actions. This work i) gives an overview of the use of octopus pot on fisheries, ii) analyses the spatial distribution of this item on the coast, and iii) discusses the potential measures for tackling the octopus pot plague on the North Atlantic Iberian coast. Overall, it is urgent to promote conducive policies and strategies for a sustainable waste management of octopus pots, based on Reduce, Reuse and Recycle hierarchical framework.

Comparative study of pristine and polluted estuaries in Souss Massa National Park (Morocco): Implications for conservation strategies

Estuaries are among the ecosystems most affected by human actions worldwide. Economic development in Morocco puts pressure on these aquatic systems, making them vulnerable. This study compares the state of benthic communities between a pristine estuary (Massa estuary) and a polluted one (Souss estuary). Both ecosystems belong to the Souss Massa National Park (SMNP), registered in the Ramsar list for its ecological importance as a Marine Protected Area (MPA). Twenty-one benthic species were identified in the pristine estuary, but only six species in the polluted one. Similar differences were detected for the species abundance and biomass. The total organic matter and the water-dissolved oxygen also revealed a notable negative effect of the sewage discharge. The results confirmed human disturbances on faunal communities related to direct wastewater inputs and indirect anthropogenic activities such as the urbanization and the litter generation. A combination of ending wastewater discharge and adding tertiary-level water treatment plants is recommended. The findings highlight the importance of MPAs in conservation strategies if coupled with continuous surveillance of pollution.