Monitoring the occurrence of microplastic ingestion in Otariids along the Peruvian and Chilean coasts

Prevalence of plastic debris in nests of two cormorant species in Peru

The guanay cormorant (Leucocarbo bougainvilliorum) and red-legged cormorant (Poikilocarbo gaimardi) are known for their prolific nest-building behavior, utilizing a diverse array of materials, including anthropogenic debris, thereby serving as valuable indicators of ocean plastic pollution. To elucidate inter-specific variations in nest plastic occurrence between these two cormorant species, we conducted a comprehensive examination of nests at 12 colonies along the Peruvian coast in 2018-2019. Our findings revealed a significantly higher occurrence of plastic in red-legged cormorant nests (mean 50 ± 27 %, N = 100 nests in 7 colonies) compared to guanay cormorant nests (mean 10 ± 20 %, 3497 nests in 8 colonies). Furthermore, the prevalence of plastic waste varied across colonies within both species. Off-white/clear plastic bags were the predominant color and type of debris found in both cormorant nests. This study is a baseline of plastic marine pollution occurrence along the Peruvian coast.

The COVID-19 pandemic "anthropause" decreased plastic ingestion in neotropic cormorants Nannopterum brasilianus in Lima, Peru

Background

The anthropause during the recent COVID-19 pandemic provided a unique opportunity to examine the impact of human activity on seabirds. Lockdowns in Peru prevented people from visiting coastal areas, thereby reducing garbage disposal on beaches and the movement of microplastics into the ocean. This cessation of activities likely led to a temporary decrease in plastic pollution in coastal regions. We aimed to investigate this phenomenon in inshore-feeding neotropic cormorants (Nannopterum brasilianus) along the Circuito de Playas Costa Verde (CPCV), situated on the coastal strip of Lima, Peru (∼ 11 million people).

Methods

We collected and analyzed fresh pellets along the CPCV before (over 11 months) and during the pandemic lockdowns (over 8 months).

Results

Our findings revealed a significant reduction in the occurrence of plastic in pellets during the pandemic period (% Oc = 2.47, n = 647 pellets) compared to pre-pandemic conditions (% Oc = 7.13, n = 800 pellets). The most common plastic debris item found in the pellets was threadlike microplastic. Additionally, our study highlights the direct correlation between human presence on beaches and the quantity of microplastics (mainly threadlike) found in cormorant pellets. We suggest that the reintroduction of these materials into the sea, previously accumulated on the coast, is likely facilitated by the movement and activity of beachgoers toward the ocean.

Anthropogenic debris in three sympatric seal species of the Western Antarctic Peninsula

Litter pollution is a growing concern, including for Antarctica and the species that inhabit this ecosystem. In this study, we investigated the microplastic contamination in three seal species that inhabit the Western Antarctic Peninsula: crabeater (Lobodon carcinophaga), leopard (Hydrurga leptonyx) and Weddell (Leptonychotes weddellii) seals. Given the worldwide ubiquity of this type of contaminant, including the Southern Ocean, we hypothesized that the three seal species would present anthropogenic debris in their feces. We examined 29 scat samples of crabeater (n = 5), leopard (n = 13) and Weddell (n = 11) seals. The chemical composition of the items found were identified using micro-Raman and micro-FTIR spectroscopies. All the samples of the three species presented anthropic particles (frequency of occurrence - %FO - 100 %). Fibers were the predominant debris, but fragments and filaments were also present. Particles smaller than 5 mm (micro debris) were predominant in all the samples. Leopard seals ingested significantly larger micro-debris in comparison with the other seal species. The dominant color was black followed by blue and white. Micro-Raman and micro-FTIR Spectroscopies revealed the presence of different anthropogenic pigments such as reactive blue 238, Indigo 3600 and copper phthalocyanine (blue and green). Carbon black was also detected in the samples, as well as plastic polymers such as polystyrene, polyester and polyethylene terephthalate (PET), polyamide, polypropylene and polyurethane These results confirm the presence of anthropogenic contamination in Antarctic seals and highlight the need for actions to mitigate the effects and reduce the contribution of debris in the Antarctic ecosystem.

Influence of the geographic location and house characteristics on the concentration of microplastics in indoor dust

Microplastics (MPs) are known for their ubiquity, having been detected in virtually any environmental compartment. However, indoor MPs concentrations are poorly studied despite being closely related to human exposure. The present study aims to evaluate the presence of MPs in settled atmospheric dust in 60 houses distributed in 12 districts of the metropolitan city of Lima, Peru, and investigate the influence of their geographical location and house characteristics. MPs concentration ranged from 0.01 to 33.9 MPs per mg of dust. Fibers and blue were the most frequent shape and color (98 % and 69 %, respectively). Also, 82 % of the particles were between 500 μm - 5 mm in size. A higher concentration of MPs was identified in the center-south of the city. The houses located on the highest floors (levels 4 to 13 to ground) displayed higher concentrations. MPs were primarily composed of polyester (PET), polypropylene (PP), and ethylene-vinyl acetate (EVA), among others. The polymers identified suggest that MPs derived from the fragmentation of components frequently found in houses, such as synthetic clothing, food storage containers, toys, carpets, floors, and curtains. The incorporation of MPs from the outside into dwellings is not ruled out. Future studies should evaluate the influence of consumption habits and housing characteristics on the abundance of MPs.

Heavy Metal Bioaccumulation in Peruvian Food and Medicinal Products

To better query regional sources of metal(loid) exposure in an under-communicated region, available scientific literature from 50 national universities (undergraduate and graduate theses and dissertations), peer-reviewed journals, and reports published in Spanish and English were synthesized with a focus on metal(loid) bioaccumulation in Peruvian food and medicinal products utilized locally. The study considered 16 metal(loid)s that are known to exert toxic impacts on humans (Hg, Al, Sb, As, Ba, Be, Cd, Cr, Sn, Ni, Ag, Pb, Se, Tl, Ti, and U). A total of 1907 individual analyses contained within 231 scientific publications largely conducted by Peruvian universities were analyzed. These analyses encompassed 239 reported species classified into five main food/medicinal groups-plants, fish, macroinvertebrates and mollusks, mammals, and "others" category. Our benchmark for comparison was the World Health Organization (Codex Alimentarius) standards. The organisms most frequently investigated included plants such as asparagus, corn, cacao, and rice; fish varieties like trout, tuna, and catfish; macroinvertebrates and mollusks including crab and shrimp; mammals such as alpaca, cow, chicken eggs, and milk; and other categories represented by propolis, honey, lichen, and edible frog. Bioaccumulation-related research increased from 2 to more than 25 publications per year between 2006 and 2022. The results indicate that Peruvian food and natural medicinal products can have dangerous levels of metal(loid)s, which can cause health problems for consumers. Many common and uncommon food/medicinal products and harmful metals identified in this analysis are not regulated on the WHO's advisory lists, suggesting the urgent need for stronger regulations to ensure public safety. In general, Cd and Pb are the metals that violated WHO standards the most, although commonly non-WHO regulated metals such as Hg, Al, As, Cr, and Ni are also a concern. Metal concentrations found in Peru are on many occasions much higher than what has been reported elsewhere. We conclude that determining the safety of food/medicinal products is challenging due to varying metal concentrations that are influenced not only by metal type but also geographical location. Given the scarcity of research findings in many regions of Peru, urgent attention is required to address this critical knowledge gap and implement effective regulatory measures to protect public health.

Evidence of plastic pollution from offshore oceanic sources in southern Chilean Patagonian fjords

The Chilean Patagonian fjords are globally renowned as one of the few remaining pristine environments on Earth; however, their ecosystems are under significant threat from climatic and anthropogenic pressures. Of particular concern is the lack of research into the impact of plastic pollution on the waters and biodiversity of these fjords. In this study, the marine environment of a secluded and sparsely populated fjord system in southern Patagonia was sampled to assess microplastics in seawater, beaches, bottom sediment, and zooplankton. Microplastics were found to be widespread across the water surface of the fjord, but with low abundances of 0.01 ± 0.01 particles m-3 (mean ± SD). The presence of microplastics in sedimentary environments (e.g., beaches and bottom sediments, 15.6 ± 15.3 and 9.8 ± 24 particles kg of dry sediment-1, respectively) provided additional evidence of plastic debris accumulation within the fjord system. Furthermore, microplastics were already bioavailable to key zooplankton species of the Patagonian food web (0.01 ± 0.02 particles individual-1), suggesting bioaccumulation. A comprehensive examination of potential microplastic inputs originating from coastal runoff, coupled with distribution of water masses, suggested minimal local contribution of microplastics to the fjord, strongly indicating that plastic litter is likely entering the area through oceanic currents. The composition and type of microplastics, primarily consisting of polyester fibers (approx. 60 %), provided further support for the proposed distant origin and transportation into the fjord by oceanographic drivers. These results raise significant concern as reveal that despite a lack of nearby population, industrial or agricultural activity, remote Patagonian fjords are still impacted by plastic pollution originating from distant sources. Prioritizing monitoring efforts is crucial for effectively assessing the future trends and ecological impact of plastic pollution in these once so-called pristine ecosystems.

Legacy and emerging contaminants in marine mammals from Argentina

Marine mammals are recognized sentinels of ecosystem health. They are susceptible to the accumulation and biomagnification of pollutants, which constitute one of the greatest threats to their survival. Legacy, such as organochlorine pesticides, and emerging contaminants, like microplastics and pharmaceuticals, may have effects on marine mammals' health at individual and population levels. Therefore, the evaluation of the risks associated with pollutants in this group is of great importance. The aim of this review is to provide information on the occurrence of legacy and emerging contaminants in marine mammals that inhabit Argentine waters. Also, to identify knowledge gaps and suggest best practices for future research. Reports of legacy contaminants referring to organochlorine pesticides and polychlorinated biphenyls were found in five species of cetaceans and two of pinnipeds. With respect to emerging pollutants, the presence of plastics was only evaluated in three species. Reported data was from at least a decade ago. Therefore, it is necessary to update existing information and conduct continuous monitoring to assess temporary trends in pollutants. All the studies were carried out in the province of Buenos Aires and Northern Patagonia indicating a knowledge gap in the southern zone of the Argentine Sea. In addition, pollutants of global environmental concern that have not been studied in Argentina are discussed. Future studies should fill these gaps and a greater effort to understand the relationships between pollutants and their effects on marine mammals is suggested. This issue will make it possible to determine thresholds for all the substances and species evaluated in order to carry out more detailed risk assessments and make decisions for the conservation of marine mammals in Argentine waters.

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.

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.

Detection and quantification of microplastic pollution in the endangered Galapagos sea lion

Marine debris pollution poses a significant global threat to biodiversity, with plastics being the primary debris type found in oceans due to their low-cost production and high demand worldwide. Microplastics (MPs, <5 mm in size) are highly bioavailable to a wide range of marine taxa, including marine mammals, through direct and indirect ingestion routes (i.e., trophic transfer). Recently, MP pollution has been detected on the Galapagos Marine Reserve, so in this study we developed a baseline framework for MP pollution in the Galapagos sea lion (GSL, Zalophus wollebaeki) through scat-based analysis. We collected 180 GSL scat samples from the southeast region following strict quality assurance/quality control protocols to detect, quantify and characterize physical-chemical properties of MPs through visual observations and μFT-IR spectroscopy. We recovered 81 MPs of varying sizes and colors in 37 % of samples (n = 66/180), consisting mostly of fibers (69 %, x¯ = 0.31 ± 0.57 particles scat-1). The number of particles per gram of sample wet weight ranged from 0.02 to 0.22 (x¯ = 0.04 ± 0.05 particles scat wet g-1). El Malecón and Punta Pitt rookeries at San Cristobal Island had the highest number of MPs (x¯ = 0.67 ± 0.51 and 0.43 ± 0.41 particles scat-1, respectively), and blue-colored particles were the most common in all samples. We identified eleven polymers in 46 particles, consisting mostly of polypropylene-polyethylene copolymer, polypropylene, cellulose, polyethylene, and polyvinyl chloride. The textile, fishing, and packaging industries are likely significant sources of microfibers into this insular ecosystem. Our results suggest that the GSL is exposed to MPs due to anthropogenic contamination that is subsequently transferred through trophic processes. These findings provide an important baseline framework and insights for future research on MP pollution in the region, as well as for management actions that will contribute to the long-term conservation of the GSL.

Microplastics in Seabird Feces from Coastal Areas of Central Chile

Pollution from plastic waste thrown into the ocean affects all levels of the food chain. Marine species of birds are affected by plastic particles of different sizes, especially the mesoplastics (1 to 10 mm) found in their digestive tract, which mainly cause obstructions. In the case of microplastics (1.000 µm to 1 mm), their presence in the digestive tract of these species has been widely reported. We studied fecal samples of the Dominican gull (Larus dominicanus) (n = 14), Magellanic penguins (Spheniscus magellanicus) (n = 8), and Humboldt penguin (Spheniscus humboldti) (n = 1) obtained from the Wildlife Rehabilitation Center of the Biobío region, Chile. Microfibers of various colors were present in the feces of Dominican gulls and Magellanic penguins, corresponding mainly in composition to polypropylene (PP) (83%) and rayon (77%). These results demonstrate that microplastic particles occur in the coastal environments of central Chile and suggest that they are probably circulating in the food chain.

Guanay cormorant (Leucocarbo bougainvilliorum) pellets as an indicator of marine plastic pollution along the Peruvian coast

Plastic pollution affects many taxa worldwide, and monitoring is crucial for understanding its impacts, particularly where plastic reaches threatened species or those destined for human consumption. This study evaluates plastic ingestion in Near Threatened guanay cormorants (Leucocarbo bougainvilliorum), which catch prey that are also targeted by fisheries, through pellet analysis at ten locations in Peru. Plastic occurred in 162 (7.08 %) of 2286 pellets, consisting of mainly user plastics, including 5 % between mega or macro (>20 mm), 23 % meso (5-20 mm), 67 % micro (1-5 mm) plastics and 5 % ultrafine (1 μm-1 mm). We found significantly higher percentages occurrence of plastic for colonies close to more river mouths. Our results show that seabird pellet sampling is a useful tool for monitoring marine plastic pollution in Peru.

Spatially and Temporally Explicit Metagenomes and Metagenome-Assembled Genomes from the Comau Fjord (42°S), Patagonia

Microbes play an important role in coastal and estuarine waters. We present 93 metagenomes and 677 metagenome-assembled genomes (MAGs) from Comau Fjord, Patagonia (42°S), to further understand the microbial dynamics and their response to anthropogenic disturbances. These data represent a spatially (35-km transect) and temporally (2016 to 2019) explicit data set.

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

Microplastics (MPs) become ubiquitous contaminants in Marine Protected Areas (MPA) that have been planned as a conservation strategy. The present study provides a comprehensive overview of the occurrence, abundance, and distribution of MPs potentially affecting MPA worldwide. Data on MP occurrence and levels in sediment and biota samples were collected from recent peer-reviewed literature and screened using a GIS-based approach overlapping MP records with MPA boundaries. MPs were found in 186 MPAs, with levels ranging from 0 to 9187.5 items/kg in sediment and up to 17,461.9 items/kg in organisms. Peaked MPs concentrations occurred within multiple-use areas, and no-take MPAs were also affected. About half of MP levels found within MPA fell into the higher concentration quartiles, suggesting potential impacts on these areas. In general, benthic species were likely more affected than pelagic ones due to the higher concentrations of MP reported in the tissues of benthic species. Alarmingly, MPs were found in tissues of two threatened species on the IUCN Red List. The findings denote urgent concerns about the effectiveness of the global system of protected areas and their proposed conservation goals.

Heavy metal contamination in pristine environments: lessons from the Juan Fernandez fur seal (Arctocephalus philippii philippii)

Heavy metals, including mercury (Hg) and cadmium (Cd), occur naturally or anthropogenically and are considered toxic to the environment and human health. However, studies on heavy metal contamination focus on locations close to industrialized settlements, while isolated environments with little human activity are often ignored due to perceived low risk. This study reports heavy metal exposure in Juan Fernandez fur seals (JFFS), a marine mammal endemic to an isolated and relatively pristine archipelago off the coast of Chile. We found exceptionally high concentrations of Cd and Hg in JFFS faeces. Indeed, they are among the highest reported for any mammalian species. Following analysis of their prey, we concluded that diet is the most likely source of Cd contamination in JFFS. Furthermore, Cd appears to be absorbed and incorporated into JFFS bones. However, it was not associated with mineral changes observed in other species, suggesting Cd tolerance/adaptations in JFFS bones. The high levels of silicon found in JFFS bones may counteract the effects of Cd. These findings are relevant to biomedical research, food security and the treatment of heavy metal contamination. It also contributes to understanding the ecological role of JFFS and highlights the need for surveillance of apparently pristine environments.

High incidence of plastic debris in Andean condors from remote areas: Evidence for marine-terrestrial trophic transfer

Plastic pollution is an alarming environmental problem affecting diverse species worldwide. Scavenging birds are currently exposed to plastic due to contamination of their food sources. Here, we evaluated the ingestion of plastic by a threatened top scavenger, the Andean condor (Vultur gryphus), and the potential origin of the plastic. We analyzed the biotic (organic items from the diet) and abiotic (synthetic material) composition of regurgitated pellets in two remote areas of Peru associated with protected areas: a marine-coastal region and an Andean region. Condors consume mainly Pinnipeds and South American camelids in the marine-coastal region, and camelids and livestock in the Andean region. We found different sizes and varieties of plastic debris, with a very high frequency of occurrence (85-100%) of microplastics in pellets of both areas studied. The occurrence of microplastics differed between sites; although very high in general, the rate of occurrence and density were higher in the marine-coastal region. We also confirmed that carcasses consumed by condors in both study areas were contaminated with plastic. Therefore, plastic in Andean condors is most probably acquired through the food web in both the marine and terrestrial environments. Andean condors from Peru are highly contaminated with plastic, which may affect their health, population dynamics, and conservation. Moreover, as condors are apex scavengers, our results highlight the fact that plastic pollution in remote areas of Peru is present at different levels of the food web and in the environment. Urgent Action should be taken to reduce environmental contamination with this hazardous pollutant.

Assessing microplastic exposure of the Critically Endangered Mediterranean monk seal (Monachus monachus) on a remote oceanic island

Microplastics (<5 mm) are a ubiquitous marine pollutant which are highly bioavailable to marine organisms across all trophic levels. Marine predators are especially vulnerable to microplastic pollution through direct and indirect ingestion (e.g., trophic transfer) due to their high trophic position. In particular, oceanic islands are more susceptible to plastic accumulation, increasing the relative number of microplastics in the environment that are available for consumption. The dynamics of microplastic accumulation in marine predators inhabiting remote islands, however, is sparsely documented. Here we describe microplastic exposure in the Critically Endangered Mediterranean monk seal (Monachus monachus) from the Madeira archipelago (Northeast Atlantic) using scat-based analysis. Microplastics were recovered from 18 scat samples collected between 2014-2021 and were characterized to the polymer level using Fourier-Transform Infrared (u-FTIR) spectroscopy. A total of 390 microplastic particles were recovered, ranging between 0.2-8.6 particles g^-1 dry weight (mean 1.84 ± 2.14 particles g^-1) consisting mainly of fragments (69 %) of various sizes and polymer composition (e.g., PE, PET, PS). Microplastic prevalence (100 % of samples analysed) was higher than what has been previously recorded using scat-based analysis in other pinniped species. Our results suggest that the levels of microplastic pollution in the coastal food-web in the Madeira archipelago are relatively high, placing higher-trophic level organisms at increased risk of microplastic consumption, including humans. This study provides the first insights into microplastic exposure to Madeira's monk seals that may contribute to future management decisions for the species and their long-term survival.

Detection of microplastic particles in scats from different colonies of California sea lions (Zalophus californianus) in the Gulf of California, Mexico: A preliminary study

Microplastics (MPs, < 5 mm in size) are highly bioavailable to many taxa within the marine ecosystem, either ingested directly or indirectly through trophic transfer from polluted prey. The ingestion analysis of these MPs from top predators, such as pinnipeds in Mexico, is relatively unexplored. Forty-eight scats from California sea lions were collected on six rookeries along the Gulf of California. From these scat samples, 294 suspected MPs particles were classified and chemically analyzed; 34% were synthetic and semi-synthetic, and 66% were non-synthetic. Blue-colored polyethylene terephthalate fibers were the most common type of MP registered. During laboratory work, multiple contamination control measures were implemented. Although the ingestion pathway is still unknown, our results support the other authors that suggest the potential trophic transfer of MPs to top predators and incidental ingestion while foraging. The particles documented here provide important baseline information for future MP research in the Gulf of California.

Microplastic Interactions and Possible Combined Biological Effects in Antarctic Marine Ecosystems

Antarctica and the Southern Ocean are the most remote regions on Earth, and their quite pristine environmental conditions are increasingly threatened by local scientific, tourism and fishing activities and long-range transport of persistent anthropogenic contaminants from lower latitudes. Plastic debris has become one of the most pervasive and ubiquitous synthetic wastes in the global environment, and even at some coastal Antarctic sites it is the most common and enduring evidence of past and recent human activities. Despite the growing scientific interest in the occurrence of microplastics (MPs) in the Antarctic environment, the lack of standardized methodologies for the collection, analysis and assessment of sample contamination in the field and in the lab does not allow us to establish their bioavailability and potential impact. Overall, most of the Southern Ocean appears to be little-affected by plastic contamination, with the exception of some coastal marine ecosystems impacted by wastewater from scientific stations and tourist vessels or by local fishing activities. Microplastics have been detected in sediments, benthic organisms, Antarctic krill and fish, but there is no clear evidence of their transfer to seabirds and marine mammals. Therefore, we suggest directing future research towards standardization of methodologies, focusing attention on nanoplastics (which probably represent the greatest biological risks) and considering the interactions of MPs with macro- and microalgae (especially sea-ice algae) and the formation of epiplastic communities. In coastal ecosystems directly impacted by human activities, the combined exposure to paint chips, metals, persistent organic pollutants (POPs), contaminants of emerging interest (CEI) and pathogenic microorganisms represents a potential danger for marine organisms. Moreover, the Southern Ocean is very sensitive to water acidification and has shown a remarkable decrease in sea-ice formation in recent years. These climate-related stresses could reduce the resilience of Antarctic marine organisms, increasing the impact of anthropogenic contaminants and pathogenic microorganisms.

First Assessment of Micro-Litter Ingested by Dolphins, Sea Turtles and Monk Seals Found Stranded along the Coasts of Samos Island, Greece

This study is the first to assess the occurrence of micro-litter ingested by marine megafauna in the north-eastern Aegean Sea. A total of 25 specimens from four species of marine mammals, including dolphins and monk seals, and two species of sea turtles, found stranded along the coastline of Samos Island, Greece, were selected for the analysis. Litter particles, identified as microplastics (MPs), were ubiquitous throughout all sections of the gastrointestinal tract (oesophagus, stomach and intestine) in all specimens. Overall, the MPs most frequently found were black fibres 0.21-0.50 mm in size. These results provide insight into the extent of micro-litter ingestion and contamination in marine vertebrates. Here we propose a method of standardisation to establish a baseline for marine taxa in this region of the Mediterranean Sea, where knowledge of the topic is still lacking.

Methods for Natural and Synthetic Polymers Recovery from Textile Waste

Trends in the textile industry show a continuous increase in the production and sale of textile materials, which in turn generates a huge amount of discarded clothing every year. This has a negative impact on the environment, on one side, by consuming resources—some of them non-renewables (to produce synthetic polymers)—and on the other side, by polluting the environment through the emission of GHGs (greenhouse gases), the generation of microplastics, and the release of toxic chemicals in the environment (dyes, chemical reagents, etc.). When natural polymers (e.g., cellulose, protein fibers) are used for the manufacturing of clothes, the negative impact is transferred to soil pollution (e.g., by using pesticides, fertilizers). In addition, for the manufacture of clothes from natural fibers, large amounts of water are consumed for irrigation. According to the European Environment Agency (EEA), the consumption of clothing is expected to increase by 63%, from 62 million tonnes in 2019 to 102 million tonnes in 2030. The current article aims to review the latest technologies that are suitable for better disposal of large quantities of textile waste.

Microplastic concentration, distribution and dynamics along one of the largest Mediterranean-climate rivers: A whole watershed approach

Microplastics (MPs) have been recognized as one of the most ubiquitous environmental pollutants globally. They have been found in all ecosystems studied to date, threatening biological diversity, ecosystem functioning and human health. The present study aimed to elucidate the environmental and anthropogenic drivers of MP dynamics in the whole catchment of the Biobío river, one of the largest rivers in South America. MP concentration and characteristics were analysed in 18 sites subjected to different sources of pollution and other human-related impacts. The sampling sites were classified in relation to altitudinal zones (highland, midland and lowland) and ecosystem types (fluvial and reservoir), and different water and territorial environmental variables were further collated and considered for analysis. Seven types of microplastic polymers were identified in the samples analysed, with a catchment mean (±SE) MP concentration of 22 ± 0.4 particles m^-3, and MP presence being significantly higher in lowlands (26 ± 2 particle m^-3) and in reservoirs (42 ± 14 particle m^-3). The most abundant type of MP was fragments (84%), with a mean concentration of 37 ± 6 particles m^-3. Overall, MP concentrations were low compared to those found in other studies, with a strong influence of human population size.

Are we underestimating floating microplastic pollution? A quantitative analysis of two sampling methodologies

Microplastics (MPs) are widespread in the water column of several aquatic ecosystems. Thus, the sampling methodology is considered as a basic factor influencing MPs abundance. In this baseline, a total of 67 investigations were chosen to conduct a quantitative analysis between two sampling methods: Trawl and bulk. The aim is to report a general overview of the MPs abundance and characteristic differences based on the sampling procedures and provide methodological recommendations. MPs abundance reported by bulk studies is 3500 higher than trawl studies. Furthermore, the morphological types and polymers abundances were statistically affected by the type of sampling tool. Conversely, MPs size ranges were significantly different between sampling procedures, suggesting that trawling underestimates the smaller MPs fractions. The analysis confirms that the sampling methods should be selected based on the research objectives. In this sense, it is recommended to combine both types of sampling procedures to obtain comprehensive data.

Microplastics in Latin America and the Caribbean: A review on current status and perspectives

A literature review was carried out to analyze the current status of microplastic research in Latin America and the Caribbean (LAC). Specifically, this work focused on publications pertaining to (1) occurrence and distribution of microplastics in the environment, including water, sediments, and soil and (2) the environmental impact of MPs, particularly their presence and effects on aquatic and terrestrial organisms. The review included peer-reviewed articles from Scopus, Science Direct, Web of Science, Google Scholar and two iberoamerican open access databases (Redalyc and SciELO). It was found that LAC has only contributed to 5% of the global scientific output on microplastics, and overall the highest contributor within the region was Brazil (52%), followed by Chile (16%) and Mexico (13%). An additional section analyzing the barriers to conducting microplastic research in LAC and their exacerbation by the current COVID-19 pandemic was included to provide additional context behind the relatively low scientific production and improve recommendations encouraging research in this region.

Using a non-invasive technique to identify suspected microplastics in grey seals (Halichoerus grypus) living in the western North Sea

BACKGROUND

Plastic pollution is of growing concern in marine ecosystems worldwide. Specifically, microplastics (<5 mm) may interact with a variety of biota with the potential to cause harm to organism health. Studies investigating microplastics are increasing, yet their occurrence within free-ranging and living marine mammals remains largely unexplored.

METHODS

By using a protocol involving enzymatic digestion, filtration and microscopic identification, faecal samples collected from a grey seal (Halichoerus grypus) haul-out site in the North Sea were investigated for microplastic presence.

RESULTS

Altogether, 71 suspected microplastic particles, consisting of both fibres and fragments in a variety of colours and sizes, were identified across 66 analysed faecal subsamples.

CONCLUSION

The present study indicates that marine mammals are ingesting microplastics and that faecal material can be used to indirectly and non-invasively record microplastic uptake data in pinnipeds. Since the current paper is the first to document potential microplastic exposure among wild, living and free-ranging grey seals of the western North Sea, further research is needed to begin to understand the biological significance of these findings.

Occurrence of Microplastics in Harbour Seals (Phoca vitulina) and Grey Seals (Halichoerus grypus) from German Waters

The level of knowledge on microplastic exposure in marine mammals is limited by the access to dead and alive individuals. Focusing on the Northeast Atlantic area, some studies already confirmed the microplastic presence in free-ranging marine mammals, such as harbour porpoises or harbour seals inhabiting the North Sea (NS). In contrast, knowledge on the exposure to grey seals and particularly on specimen inhabiting the Baltic Sea (BS) are scarce. This study examined 63 gastrointestinal tracts (GIT) of harbour seals and grey seals originating from German waters (NS and BS) found between 2014 and 2019. Besides the documentation of microplastic findings, this study is dealing with life history and health parameters, attempting to identify correlations with microplastic presence. This study confirmed beside the presence, the egestion of microplastics (>100 µm; MPs) in the examined seals, without correlations in parasite infestations or inflammation responses. 540 suspected MPs were identified in 62 intestinal samples (42% fibres, 58% fragments), and 228 MPs in seven stomachs (28% fibres, 72% fragments). In accordance, first evidence of the retainment of fragments in the GIT were given. However, no significant difference in MP occurrence was indicated for different sex or age groups.

Positively buoyant but sinking: Polymer identification and composition of marine litter at the seafloor of the North Sea and Baltic Sea

Different litter types accumulate in all marine environments. Plastics are of special interest because of their high abundance and possible threats to marine organisms. Polymer type is crucial for their distribution and fate in marine environments. Seafloor litter abundance and composition in the Baltic and North Sea were analysed based on three sampling campaigns according to the protocol of ICES International Bottom Trawl Survey. Polymers were identified via attenuated total reflection-Fourier transform infrared spectroscopy. General litter abundances differed significantly between the Baltic and North Sea with 9.6 items/km² and 70.7 items/km², respectively. Plastic built the dominating litter group in both seas (62.2% and 91.3%, respectively). Polymer identification revealed clear dominance of polyethylene, polypropylene and polyamide. Most polymers were positively buoyant in seawater (89.5%), thereby excluding polymer density as the main driver of vertical plastic litter transportation. Plastics at the seafloor basically reflected the entirety of polymers entering marine environments.

Critical review on microplastics in fecal matter: Research progress, analytical methods and future outlook

There has been an ever-increasing attention over years for investigating microplastics in feces of lower to higher trophic organisms from diverse environments. Focusing on the standardization of methodologies for reliable generation and comparison of data is one of the important aspects in microplastic area. This first review, comprising 20 studies in total, critically summarizes and compares the methodological approaches for the determination of microplastics in feces as well outlines the levels and characteristics of microplastics detected in feces worldwide. Contaminations and QA/QC measures are also discussed. Despite variations among the approaches, most studies (n = 12) described herein rely on the digestion processes involving H₂O₂ (n = 7) and KOH (n = 6) for the separation of microplastics, whereas very few included wet sieving (n = 5), density separation using NaCl (n = 3) and NaI (n = 1) and enzymatic digestion (n = 2). Microscopical sorting and spectroscopic methods such as infrared and Raman were combined for identification and characterization of microplastics. The detected microplastics varied by size, shape, color and polymer types and the differences in reporting units of microplastic abundance make comparison across studies difficult. Taking advantage of the current knowledge, our review identified analytical challenges and suggested appropriate methods on research into microplastic contamination in feces. This work will serve as a valuable information of available analytical methods for examining microplastics in feces and will stimulate further research to advance our understanding of microplastics from feces.

COVID-19 pandemic repercussions on plastic and antiviral polymeric textile causing pollution on beaches and coasts of South America

The propagation of the COVID-19 pandemic worldwide has been alarming in the last months. According to recommendations of the World Health Organization (WHO), the use of face masks is essential for slowing down the transmission rate of COVID-19 in human beings. This pandemic has generated a substantial increase in the use, as well as in the production, of face masks and other elements (gloves, face protectors, protective suits, safety shoes) manufactured with polymeric materials, including antiviral textiles most of which will end as microplastic pools. Focusing on South America, the use and mismanagement of this type of personal protective equipment (PPE) represents an environmental problem. Added to this issue are the increase in the use of single-use plastic, and the reduction of plastic recycling due to the curfew generated by the pandemic, further aggravating plastic pollution on coasts and beaches. Recently, researchers have developed antiviral polymeric textile technology composed of Ag and Cu nanoparticles for PPE to reduce the contagion and spread of COVID-19. Antiviral polymeric textile wastes could also have long-term negative repercussions on aquatic environments, as they are an important emerging class of contaminants. For this reason, this work provides reflections and perspectives on how the COVID-19 pandemic can aggravate plastic pollution on beaches and coastal environments, consequently increasing the damage to marine species in the coming years. In addition, the potential impact of the pandemic on waste management systems is discussed here, as well as future research directions to improve integrated coastal management strategies.

Marine mammals and microplastics: A systematic review and call for standardisation

Microplastics receive significant societal and scientific attention due to increasing concerns about their impact on the environment and human health. Marine mammals are considered indicators for marine ecosystem health and many species are of conservation concern due to a multitude of anthropogenic stressors. Marine mammals may be vulnerable to microplastic exposure from the environment, via direct ingestion from sea water, and indirect uptake from their prey. Here we present the first systematic review of literature on microplastics and marine mammals, composing of 30 studies in total. The majority of studies examined the gastrointestinal tracts of beached, bycaught or hunted cetaceans and pinnipeds, and found that microplastics were present in all but one study, and the abundance varied between 0 and 88 particles per animal. Additionally, microplastics in pinniped scats (faeces) were detected in eight out of ten studies, with incidences ranging from 0% of animals to 100%. Our review highlights considerable methodological and reporting deficiencies and differences among papers, making comparisons and extrapolation across studies difficult. We suggest best practices to avoid these issues in future studies. In addition to empirical studies that quantified microplastics in animals and scat, ten studies out of 30 (all focussing on cetaceans) tried to estimate the risk of exposure using two main approaches; i) overlaying microplastic in the environment (water or prey) with cetacean habitat or ii) proposing biological or chemical biomarkers of exposure. We discuss advice and best practices on research into the exposure and impact of microplastics in marine mammals. This work on marine ecosystem health indicator species will provide valuable and comparable information in the future.

Review of current trends, advances and analytical challenges for microplastics contamination in Latin America

Microplastics accumulation is an emerging environmental issue and a threat to marine life and human health. There is a growing number of investigations on the abundance and distribution of microplastics in different water bodies and biota worldwide, with relatively few studies conducted in Latin America, however, the current knowledge of microplastics sources, occurrence, transport, fate and potential impacts remains largely unexplored. This review presents the current trends and advances of microplastics on a lesser known region of the world by compiling the research performed to date in different environmental compartments. The sampling techniques and methods for microplastics extraction in the existing literature data are also summarized. Among 78 published studies reviewed, 34% of studies were from Brazil and 46% of studies have mainly focused on biota. The main findings showed that microplastics are not negligible across Latin America significantly varying in their distribution, with the prevalence of fibers comprising 62% of the total. Polyethylene, polypropylene, polyethylene terephthalate and polystyrene have been identified as the most common polymer types, accounting for 80% of the total. Limited studies and lack of standardized methodologies render difficulties to establish fundamental information on microplastics abundance and types in most countries of this region. Therefore, this review will primarily serve as a baseline when evaluating the environmental relevance of microplastics in Latin America and would stimulate discussions focusing on this topic, calling for more research in future.

No evidence of microplastics in Antarctic fur seal scats from a hotspot of human activity in Western Antarctica

Microplastics are present in almost all seas and oceans, including the Southern Ocean. To the south of the Antarctic Polar Front, microplastics are present mainly west to the Antarctic Peninsula, but information is scarce about their impact on the pelagic food web. Here, we analysed 42 scats of male Antarctic fur seals (Arctocephalus gazella) collected in late summer at Deception Island (South Shetland Islands), which allowed us to assess the presence of microplastics in the pelagic food web of the Bransfield Strait (Western Antarctica). Furthermore, we analysed the hard remains of prey in the scats to characterize the diet of fur seals. Hard remains recovered from the scats revealed that male Antarctic fur seals foraged on krill and myctophid fishes during late summer. Fourier-transform infrared spectroscopy (FT-IR) revealed that none of the seven fragments and three fibres recovered from their scats were microplastics, but rather were silicate minerals and chitin. These results suggest that the levels of microplastic pollution in the pelagic food web of the Bransfield Strait are extremely low.

Microplastics in Sea Turtles, Marine Mammals and Humans: A One Environmental Health Perspective

Microplastics are ubiquitous pollutants in the marine environment and a health concern. They are generated directly for commercial purposes or indirectly from the breakdown of larger plastics. Examining a toxicological profile for microplastics is a challenge due to their large variety of physico-chemical properties and toxicological behavior. In addition to their concentration, other parameters such as polymer type, size, shape and color are important to consider in their potential toxicity. Microplastics can adsorb pollutants such as polycyclic aromatic hydrocarbons (PAHs) or metals on their surface and are likely to contain plastic additives that add to their toxicity. The observations of microplastics in seafood increased concern for potential human exposure. Since literature considering microplastics in humans is scarce, using a One Environmental Health approach can help better inform about potential human exposures. Marine mammals and sea turtles are long-lived sentinel species regularly used for biomonitoring the health status of the ocean and share trophic chain and habitat with humans. This review considers the available research regarding microplastic and plastic fiber exposures in humans, marine mammals and turtles. Overall, across the literature, the concentration of microplastics, size, color, shape and polymer types found in GI tract and feces from sea turtles, marine mammals and humans are similar, showing that they might be exposed to the same microplastics profile. Additionally, even if ingestion is a major route of exposure due to contaminated food and water, dermal and inhalation studies in humans have provided data showing that these exposures are also health concerns and more effort on these routes of exposures is needed. In vitro studies looked at a variety of endpoints showing that microplastics can induce immune response, oxidative stress, cytotoxicity, alter membrane integrity and cause differential expression of genes. However, these studies only considered three polymer types and short-term exposures, whereas, due to physiological relevance, prolonged exposures might be more informative.