Microplastics in the tissues of commercial semi-intensive shrimp pond-farmed Litopenaeus vannamei from the Gulf of California ecoregion

Quantitative assessment of microplastics in fish from the Gulf of Guinea, Ghana, using LDIR spectroscopy: Implications for marine food safety and health risk evaluation

In this study, microplastic (MP) contamination was investigated in 24 marine fish species from 3 environmental hotspots- Labadi, Teshie, and Jamestown, along Ghana's Gulf of Guinea coastline. Specific fish species studied included Pseudotolithus senegalensis, Sphyraena guachancho, Brachydeuterus auratus, Chloroscombrus chrysurus, and Ethmalosa frimbriata. Fifty-eight percent of the total MPs were detected in the gastrointestinal tracts, and 42% detected in gills of 177 individual fish tested in this study. Labadi showed the highest contamination levels [mean MP concentration: 22 ± 19 (items fish)-1]. Omnivorous fish species had the highest mean ingestion rate of MPs (19.4), surpassing both carnivorous (17.7) and herbivorous species (13.5), and indicating dietary habits as a significant factor in MP bioaccumulation. White-coloured MP films (60%) of sizes: 100-1000 µm were the dominant ingested shape. Other MP shapes included fragments (26.3%), fibres (10.5%), beads (1.05%), and foam (0.61%). Using advanced spectroscopic technique such as Laser Direct Infrared (LDIR) Imaging, 16 MP polymers were characterized with polyvinyl chloride (PVC) being the prevalent MP polymer type (80%). The study observed a strong positive correlation between carnivorous demersal and omnivorous pelagic-neritic fish for specific MP polymers, suggesting that factors other than polymer density influence MP consumption patterns for fish habitats within the water column. The annual MP exposure to Ghanaian adults via fish consumption [(194-29,239 MP items (person year)-1] significantly exceeded the European Safety guidelines [518-3078 (items year)-1], emphasizing dietary habits and environmental pollution as key factors. This study provides a critical baseline on MP pollution in Ghanaian marine ecosystems, highlighting the urgent need for interventions to mitigate plastic pollution, protect marine biodiversity, safeguard marine food, and public health in West Africa.

Occurrence and human exposure risk of microplastics in commercially important shrimp species from Northeastern Mediterranean Sea

Microplastics (MPs) are ubiquitous pollutants in marine environment and monitoring studies have been conducted to understand microplastic presence in aquatic biota. However, studies addressing the microplastic abundance in invertible species are scant. This study aims to investigate presence of ingested microplastics in three commercial shrimp species (Metapenaeus monoceros, Plesionika martia and Melicertus hathor). Mean microplastic abundance (with standard error) in the digestive organs was found as 0.76 ± 1.0 MPs/ind and 0.86 ± 1.5 MPs/g wet weight. No significant difference was detected between species. Fiber (87 %), black (53 %), <500 μm (62 %) microplastic particles was dominant. A negative correlation was found between shrimp weight and ingested microplastic amount (r:-0.46, p:0.005). FTIR analysis showed polyethylene (PE) and polypropylene (PP) as identified polymers. Results proved microplastic exposure in shrimp species from İskenderun Bay and average of 14 to 441 MPs per year could be transferred to human body upon consumption. Therefore, study results showed the microplastic exposure risk depending on consumption of crustacean species and underlined the need of protective measures.

Influence of anthropogenic pressures on the microplastic distribution in the riverine-estuarine environment: A source-apportioning approach

In this study, the influence of anthropogenic pressures, namely fishing practices and illicit and unregulated wastewater and solid waste discharge, on the microplastic distribution in India's Kallada River - Ashtamudi riverine-estuarine environment was investigated. To better characterize microplastic pollution in the Estuary, it was subdivided into cage farming, open fishing, solid waste dumping, and other zones that receive wastewater from residential areas. A source-apportioning approach was utilized to delineate the possible sources of pollution and conducted a risk assessment attributed to exposure to microplastic pollution. The results suggest that the solid waste dumping zone exhibited the highest microplastic abundance, followed by the cage farming zone. Fiber-shaped microplastic particles were abundant in cage farming and open fishing zones, while films dominated the solid waste dumping zone. FTIR analysis revealed that polyamide and polyester, widely used for regional fishing nets, were dominant in cage farming and open fishing zones, while polyamide, polystyrene, and polyethylene were dominant in solid waste dumping zones. Other zones impacted by the unregulated discharge of domestic wastewater exhibited an abundance of polyester and polyethylene microplastics. Source apportionment studies using a modified approach incorporating morphological and chemical characteristics of microplastics revealed that fishing nets/ropes contributed to 35.48 % of microplastic pollution, followed by single-use plastics and plastic bags/covers (19.35 % each), textile fabrics (16.13 %) and personal care products (9.68 %). A risk assessment analysis considering microplastic abundance and polymer hazard revealed that the solid waste dumping zone and the cage farming zone pose a medium risk to microplastic pollution. These findings highlight the role of fishing practices and solid waste dumping on the microplastic pollution in the riverine-estuarine environment.

Temporal variability of microplastics in shrimp (Litopenaeus vannamei), feed, water and sediments of coastal and inland culture ponds

Aquaculture, particularly shrimp farming, is crucial for global food security. However, the increasing presence of microplastics (MPs) in marine environments, shrimp feeds, and atmospheric particles has made MP contamination in shrimp tissues inevitable. This study systematically investigates the abundance, characteristics, and temporal trends (from 15th to the 120th day of culture) of MPs contamination in Litopenaeus vannamei, along with associated feed, water, and sediment across 12 shrimp ponds of two major shrimp-producing regions of India. MPs were detected in 93.7 % of shrimp samples and all environmental matrices, with the highest abundance recorded in coastal culture ponds. The overall average MPs abundance in shrimp was 4.07 items/individual (1.24 MPs items/g). MP sizes ranged from 8 μm to 4.22 mm, with MPs smaller than 100 μm being predominant in shrimp samples, though their prevalence decreased over the culture period. Fragments and fibers were the dominant morphotypes across all matrices, with a shift towards larger MPs and an increased proportion of fibers and films over time. Micro FTIR analyses revealed polyethylene (PE) and polypropylene (PP) were the most common polymers detected, indicating their widespread environmental distribution. Feed was identified as the primary source of MPs contamination in shrimp. The presence of MPs in shrimp raises significant concerns for consumer health, food safety, and trade, as shrimp are among the most widely consumed aquatic food products. This study underscores the dynamics of MP contamination in shrimp aquaculture and highlights the urgent need for targeted strategies to mitigate contamination, ensuring consumer safety and industry sustainability.

A critical review of microplastics in the shrimp farming environment: Incidence, characteristics, effects, and a first mass balance model

This review provides a critical overview of the sources, incidence, accumulation, effects, and interactions of microplastics (MPs) with other contaminants in the shrimp aquaculture environment, emphasizing this sector's challenges and future implications. A first and novel mass MPs balance model was developed to explore the fate and fluxes of MPs within shrimp farming systems. Two literature searches were conducted: one focused on MPs, crustaceans, and shrimp in aquaculture, and other on the effects of MPs in crustaceans, emphasizing shrimp. A total of 78 and 461 peer-reviewed papers were retrieved, respectively. This review details aspects of MPs in the shrimp farming environment, including water, sediments, food, zooplankton, and shrimp tissues. MPs can act as vectors for contaminants, including biological and chemical substances commonly used in shrimp aquaculture. A primary concern is the interaction between MPs and pathogens; thus MPs can facilitate the transport and retention of disease-causing agents. Key questions involve identifying which pathogen groups are most efficiently transported by MPs and how this may exacerbate disease outbreaks in aquaculture. This suggests that microorganisms can establish on MPs surfaces to disseminate an infection. Therefore, the possibility of disease outbreaks and epidemics is expected to rise as MP abundance increases. The mass balance shows that the primary source of MPs is associated with water during the filled (19.3 %) and water exchange (77.2 %) of shrimp ponds, indicating that MPs in the water input play a critical role in the MP dynamic in the shrimp farming environment. However, this initial mass balance model has several weaknesses, including liming, atmospheric deposition, and natural food, which must be addressed as other MPs suppliers. Macrofauna that incidentally enters shrimp ponds may also constitute a significant part of the MPs inventory. Future research should focus on the impact of polystyrene and polyethylene fibers commonly found in crustacean tissues.

Microplastics in aquaculture environments: Current occurrence, adverse effects, ecological risk, and nature-based mitigation solutions

Microplastics pose detrimental effects on the environment, aquatic products, and human health. This comprehensive analysis highlights the repercussions of microplastic contamination within aquaculture. Microplastics in aquaculture are primarily from land-based plastic waste, tourism-related disposal, shipping activities, fisheries/aquaculture, and atmospheric deposition. In aquaculture environments, microplastics have the potential to discharge harmful additives, attract pollutants, degrade the aquaculture setting, and induce toxicological effects. These particles pose ecological risks and can impact human health. Assessing the destiny of microplastics in aquaculture ecosystems is crucial to determining the role of aquaculture in contributing to microplastic contamination within the watershed. It particularly emphasizes the ecological consequences for aquaculture species and the subsequent health threats for humans. The review strongly supports strict regulations to control and limit microplastic presence within aquaculture ecosystems. Clear regulations are essential for reducing microplastics in aquaculture, thereby ensuring food safety. A novel nature-based solution is proposed using methods like microplastic biofilters, biodegradation, and wetlands. These innovations can be conducted in aquatic ecosystems to serve as microplastic biofilters, effectively eliminating waterborne microplastics. In the future, however, it is crucial to develop additional emergency treatment measures to avoid the potential negative impacts of microplastics on both aquaculture and human health.

Potential use of gammarus (Pontogammarus maeoticus) and shrimp (Palaemon elegans) as biomonitors of microplastics pollution in coastal environments

Microplastics (MPs) pose a significant threat to marine ecosystems, necessitating robust biomonitoring to assess aquatic risks and inform effective policymaking. In this study we investigated MPs pollution in gammarus (Pontogammarus maeoticus), shrimp (Palaemon elegans), sediment and water samples of southern coast of the Caspian Sea to assess the potential use of these two crustaceans as biomonitors of MPs pollution, bioconcentration of MPs in organisms' tissue and the pollution risks of MPs in environmental matrices. Samples were collected from 6 stations during June to August 2023. MPs were found in all compartments with an average of 100 ± 45.34 items/kg dry weight, 0.45 ± 0.06 items/L, 0.38 ± 0.21 items/individual or 0.58 ± 0.34 items/g wet weight (ww) and 0.26 ± 0.15 items/individual or 8.69 ± 7.88 items/g ww, for sediments, seawaters, P. elegans and P. maeoticus, respectively. MPs were prevailed by class 300-1000 μm in size, polyamide in polymer, fiber in shape and black in color. P. maeoticus and P. elegans did not meet the selection criteria as MPs biomonitors. However, bioconcentration factor (BCF) illustrated that both crustaceans can absorb and accumulate MPs from their surrounding water (BCF >1). Based on contamination factors (CF) values, sampling stations were polluted with MPs (1 ≤ CF < 6). The overall pollution load index (PLI) for sediment and seawater stations were 2.47 and 1.88, respectively, indicating minor contamination with MPs in the risk level I. Current research provides useful information on MPs pollution in crustaceans species and the risk level of MPs in environmental matrices that can be suitable for bioaccumulation hazard assessment and future monitoring programs.

Effects of biodegradable microplastics on the crustacean isopod Idotea balthica basteri Audouin, 1826

Plastic pollution is a notable environmental issue, being plastic widespread and characterized by long lifetime. Serious environmental problems are caused by the improper management of plastic end-of-life. In fact, plastic litter is currently detected in any environment. Biodegradable Polymers (BPs) are promising materials if correctly applied and managed at their end of life, to minimize environmental problems. However, poor data on the fate and toxicity of BPs on marine organisms still limit their applicability. In this work we tested the effects of five biodegradable polymers (polybutylene succinate, PBS; polybutylene succinate-co-butylene adipate, PBSA; polycaprolactone, PCL; poly (3-hydroxybutyrates, PHB; polylactic acid, PLA) widely used for several purposes. Adult individuals of the isopod Idotea balthica basteri were fed on these polymers for twenty-seven days by adding biodegradable microplastic polymers (BMPs) to formulated feeds at two concentrations, viz. 0.84 and 8.4 g/kg feed. The plastic fragments affected the mortality rates of the isopods, as well as the expression levels of eighteen genes (tested by Real Time qPCR) involved in stress response and detoxification processes. Our findings confirmed that I. balthica basteri is a convenient model organism to study the response to environmental pollution and emerging contaminants in the aquatic environment, and highlighted the need for the correct use of BMPs.

The use of chitosan as an antioxidant in the feed of cultivated P. vannamei shrimp against oxidative stress induced by exposure to microplastics

Microplastics (MP) are omnipresent in aquaculture and can induce several toxic effects, mainly oxidative stress. Therefore, alternatives to minimize these effects are welcome. In this study, chitosan (1 and 3 g/kg) was supplemented through the feed of farmed shrimp P. vannamei for 30 days. After this period, the shrimp were exposed to MP (0.5 mg/L) for 7 days. The results showed the presence of MP in hepatopancreas, gills and muscle. Hepatopancreas morphological alterations, as well as lipid peroxidation, a decrease in GSH level, and an increase in SOD activity indicated an oxidative stress that was reversed by chitosan. The muscle was also affected by MP, showing decreased CAT activity and increased SOD activity, though no lipid peroxidation was observed. In muscle, chitosan reversed the SOD increase to basal activity. The results obtained showed that chitosan was more effective against oxidative stress than in preventing accumulation and histological damage.

Toxicokinetics of microplastics in Macrobrachium nipponense and their impact on the bioavailability of loaded pollutants

Microplastics (MPs) have unique toxicokinetic (TK) processes that differ from those of soluble pollutants. This study investigated the ingestion, migration, accumulation, and clearance of environmental aging MPs in the Japanese swamp shrimp (Macrobrachium nipponense). The concentrations of plastic additives and personal care products adsorbed onto MPs in natural river water were determined, and TK models for MPs and MPs-loaded pollutants were developed. Results showed that the formation of surface biofilms and alterations in the distribution of MPs in waters caused by environmental aging affect MPs bioavailability, which is mainly related to the feeding habits of shrimp. The decrease in MPs particle size caused by biological digestion and the increase in the number of oxygen-containing functional groups caused by environmental aging affect the TK process of MPs. The TK model of MPs-loaded pollutants revealed the cleaning effect of shrimp on pollutants adsorbed onto MPs during swallowing and spitting MPs. This cleaning effect significantly increases the bioavailability of MPs-associated pollutants in aquatic environments. This study provides a new perspective for understanding the interactions between environmental MPs and their associated pollutants in aquatic ecosystems.

Incidence of microplastics in Indian anchovy Stolephorus indicus from Tuticorin, Southeast coast of India

In the present study, the occurrence of microplastics (MPs) in the gut, gill, and muscle of edible fish Stolephorus indicus sampled from Tuticorin coastal regions of Tamilnadu, India was investigated. We recorded a total of 689 MPs which includes 510 and 179 MPs from males and females respectively. The total abundance of MPs was significantly (P < 0.05) higher in the gut followed by gills and muscle. The sex-wise distribution of average MPs showed high in the females' gut and compared to that in males. Further, the length wise distribution of MPs was higher in the muscle in both male and female fish, followed by other organs. The predominance of MPs in tissues were transparent and blue colour with fibers and fragments in both males and females. Besides, polyethylene terephthalate and nylon were evidenced by the Fourier-transform infrared spectroscopy spectrum in all organs of fishes.

Farmed stage (age)-dependent accumulation and size of microplastics in Litopenaeus vannamei shrimp reared in a super-intensive controlled system

The abundance of microplastics (MPs) in the gastrointestinal tract (GT), gills (GI), and exoskeleton (EX) of Litopenaeus vannamei shrimp cultured in a commercial indoor super-intensive controlled (ISCO) system was investigated. Shrimp of 25 days (postlarvae; PL25), and one, three, five, and seven culture months were analyzed. The postlarvae PL25 MP abundance per individual and gram of PL (wet weight) was 0.2 ± 0.0 MPs and 3.5 ± 0.5 MPs/g. For L. vannamei juveniles at one, three, five, and seven culture months, the MP abundance per juvenile shrimp was 10.0 ± 0.3, 27.2 ± 1.6, 32.3 ± 3.1, and 40.3 ± 3.6 MPs/individual, respectively (expressed in MPs/g of tissue were 1.6 ± 0.1, 2.0 ± 0.2, 2.0 ± 0.3 and 1.5 ± 0.2, respectively). Fibers were the most common MP type in all shrimp age classes (42.1-68.7 %), and the predominant color was transparent (46.1-65.0 %). The MP size in all shrimp stages ranged between 15 and 4686 μm. In general, the predominant polymers identified were PE (37.4 %), NY (21.1 %), and PET (18.5 %). The MP variability through the culture cycle showed that as the age of shrimp increased, and the culture advanced the MP abundance and size also augmented. Conversely, there is a higher MP abundance in L. vannamei cultured in ISCO systems compared to shrimp cultured in traditional semi-intensive and intensive ponds and those from wild environments. The latter is probably due to the extensive use of plasticized materials (geomembrane and greenhouse installations) and their degradation, which cause a greater MP exposure to shrimp. The estimated oral MP intake by ISCO shrimp consumption was 647 MPs/capita/year, which can be 178 % more than from wild shrimp.

Regulatory Science Perspective on the Analysis of Microplastics and Nanoplastics in Human Food

Microplastics are increasingly reported, not only in the environment but also in a wide range of food commodities. While studies on microplastics in food abound, the current state of science is limited in its application to regulatory risk assessment by a continued lack of standardized definitions, reference materials, sample collection and preparation procedures, fit-for purpose analytical methods for real-world and environmentally relevant plastic mixtures, and appropriate quality controls. This is particularly the case for nanoplastics. These methodological challenges hinder robust, quantitative exposure assessments of microplastic and nanoplastic mixtures from food consumption. Furthermore, limited toxicological studies on whether microplastics and nanoplastics adversely impact human health are also impeded by methodology challenges. Food safety regulatory agencies must consider both the exposure and the risk of contaminants of emerging concern to ascertain potential harm. Foundational to this effort is access to and application of analytical methods with the capability to quantify and characterize micro- and nanoscale sized polymers in complex food matrices. However, the early stages of method development and application of early stage methods to study the distribution and potential health effects of microplastics and nanoplastics in food have largely been done without consideration of the stringent requirements of methods to inform regulatory activities. We provide regulatory science perspectives on the state of knowledge regarding the occurrence of microplastics and nanoplastics in food and present our general approach for developing, validating, and implementing analytical methods for regulatory purposes.

Microplastics in the stomach content of the commercial fish species Scomber colias in the Gulf of Cadiz, SW Europe

Concerning microplastics (MPs) contamination is increasing due their negative impacts on marine food webs and their potential toxicity to wildlife and humans. In this study, we analyze the presence of MPs in the stomachs of the commercial fish species Scomber colias (Atlantic chub mackerel) in the Gulf of Cadiz (GoC). Out of the 104 analyzed stomachs, 90.4 % contained some type of MPs, with an average of 5.4 MPs per individual. Of the 1152 MPs analyzed, 91.1 % were fibers, and 8.9 % fragments type. Fourier Transformation Infrared Spectrometry analysis was performed on 152 items, revealing that 73.6 % were MPs. The most common synthetic polymers found were polyamide (64 %), polypropylene (15 %), polystyrene (12 %), polyvinyl chloride (5 %), and polyethylene (4 %). The consistent ingestion of synthetic polymers by the individuals of Atlantic chub mackerel across different zones might suggest an even distribution of MP contamination throughout the GoC.

Environmental and ecological risk of microplastics in the surface waters and gastrointestinal tract of skipjack tuna (Katsuwonus pelamis) around the Lakshadweep Islands, India

The presence of microplastics (MPs) in marine ecosystems is widespread and extensive. They have even reached the deepest parts of the ocean and polar regions. The number of articles on plastic pollution has increased in recent years, but few have investigated the MPs from oceanic islands which are biodiversity hotspots. We investigated the possible microplastic contamination their source and characteristics in surface waters off Kavaratti Island and in the gastrointestinal tract (GT) of skipjack tuna, Katsuwonus pelamis collected from Kavaratti Island of the Lakshadweep archipelago. A total of 424 MP particles were isolated from the surface water samples collected from off Kavaratti Island with an average abundance of 5 ± 1nos./L. A total of 117 MPs were recovered from the GT of skipjack tuna from 30 individual fishes. This points to a potential threat of MP contamination in seafood around the world since this species has a high value in local and international markets. Fiber and blue color were the most common microplastic morphotypes and colors encountered, respectively, both from surface water and GT of fish. Smaller MPs (0.01-1 mm) made up a greater portion of the recovered materials, and most of them were secondary MPs. Polyethylene and polypropylene were the most abundant polymers found in this study. The Pollution Load Index (1.3 ± 0.21) of the surface water and skipjack tuna (1 ± 0.7) indicates a minor ecological risk for the coral islands, while the Polymer Hazard Index highlights the ecological risk of polymers, even at low MP concentrations. This pioneer study sheds preliminary light on the abundance, properties, and environmental risks of MPs to this highly biodiverse ecosystem.

The occurrence of pollutants in organisms and water of inland mariculture systems: Shrimp aquaculture is a procession of Microplastics accumulation

Microplastics (MPs) pollution in the ocean was widely concerned, but the current study on MPs pollution in the mariculture system is relatively lacking. This study researched the MPs pollution characteristics in water and shrimp at different stages of the pond and industrial aquaculture. The study shows that in the same aquaculture stage, MPs abundance in shrimp and water in pond aquaculture mode is higher than that in industrial aquaculture mode. The MPs pollution characteristics in shrimp and water show significant consistency. The hazard index of MPs in pond water and industrial models are 122 (Level Ⅲ) and 540 (Level Ⅲ), respectively, indicating that industrial aquaculture models may suffer from more severe MPs stress. The aquaculture period and mode significantly affected the MPs abundance of water and shrimp, but there was no interaction between the aquaculture period and mode. MPs abundance in shrimp show a significant relationship with the length of crustacean and weight. This study further enhanced the understanding of MPs pollution of water and organisms in different aquaculture modes at different stages, and warned MPs is widely spread in mariculture systems.

Microplastics and heavy metals in shrimp Litopenaeus vannamei from the SAMARE lagoon, Gulf of California: Is it a case of combined MPs-Zn pollution in gills?

Microplastic (MPs) pollution studies in the coastal environment are increasing, as observed in the growing number of documents published yearly. However, studies regarding the combined effect of MPs and heavy metal (HMs) pollution are scarce, particularly in marine biota. Microplastics and HMs were investigated in the exoskeleton (EX), gills (GI), gastrointestinal tract (GT), and muscle (MU) of the shrimp Litopenaeus vannamei from the Santa María-La Reforma (SAMARE) lagoon, Mexico. Results showed that shrimp ingest mainly MPs of the fiber type (74.7%) and fragments (22.7%). The most frequent MP colors in the four tissues were transparent (61.4%-72.2%) and blue (3.2-36.4%) fibers. Microplastic abundance in the four tissues was 5.5 ± 0.5 MPs per individual. The predominant polymers found in most tissues were cotton and synthetic polyethylene-terephthalate (PET). Heavy metals exhibited wide variability depending on the tissue and metal; the highest Cu concentration in the GI was 138 ± 16 μg/g, while the highest Cd value was 0.40 ± 0.11 μg/g, Ni was 17.0 ± 8.3 μg/g, and Zn was 120 ± 18 μg/g in the GT. The relationship between MPs and HMs was significant and positive (p < 0.05) between MPs and Zn in the GI. This reveals a possible MPs-Zn interaction due to cotton and PET reactivity or is related to polymer manufacture. This study implies that an essential part of the world fisheries is a potential route for MPs and HMs. The problem is exacerbated due to the consumption of whole shrimp tissues consumed by humans. Considering Mexican shrimp consumption, and MPs in this study, the estimated intake was 594 MPs/capita/year. Future research requires MP monitoring in coastal lagoons that support wildlife and important fisheries and assess their effects combined with HMs.

Occurrence and Characteristics of Microplastics in Wild and Farmed Shrimps Collected from Cau Hai Lagoon, Central Vietnam

This study investigated the occurrence of microplastics (MPs) in the gastrointestinal tracts (GT) and tissues of four common shrimps (including two wild-caught shrimps and two farmed shrimps) collected from a high-diversity lagoon in central Vietnam. The numbers of MP items in greasy-back shrimp (Metapenaeus ensis), green tiger shrimp (Penaeus semisulcatus), white-leg shrimp (Litopenaeus vannamei), and giant tiger shrimp (Penaeus monodon), determined per weight and individual, were 0.7 ± 0.3, 0.6 ± 0.2, 1.1 ± 0.4, and 0.5 ± 0.3 (items/g-ww), and 2.5 ± 0.5, 2.3 ± 0.7, 8.6 ± 3.5, 7.7 ± 3.5 (items/individual), respectively. The concentration of microplastics in the GT samples was significantly higher than that in the tissue samples (p < 0.05). The number of microplastics in the farmed shrimp (white-leg shrimp and black tiger shrimp) was statistically significantly higher than the number of microplastics in the wild-caught shrimp (greasy-back and green tiger shrimps) (p <0.05). Fibers and fragments were the dominant shapes of the MPs, followed by pellets, and these accounted for 42-69%, 22-57%, and 0-27% of the total microplastics, respectively. The chemical compositions determined using FTIR confirmed six polymers, in which rayon was the most abundant polymer, accounting for 61.9% of the MPs found, followed by polyamide (10.5%), PET (6.7%), polyethylene (5.7%), polyacrylic (5.8%), and polystyrene (3.8%). As the first investigation on the MPs in shrimps from Cau Hai Lagoon, central Vietnam, this study provides useful information on the occurrences and characteristics of the microplastics in the gastrointestinal tracts and tissues of four shrimp species that live in different living conditions.

Tissue accumulation of polystyrene microplastics causes oxidative stress, hepatopancreatic injury and metabolome alterations in Litopenaeus vannamei

Microplastics (MPs) pose one of the major environmental threats to marine organisms and ecosystems on a global scale. Although many marine crustaceans are highly susceptible to MPs pollution, the toxicological effects and mechanisms of MPs on crustaceans are poorly understood. The current study focused on the impacts of MPs accumulation in shrimp Litopenaeus vannamei at the behavioral, histological and biochemical levels. The results demonstrated the accumulation of polystyrene MPs in various organs of L. vannamei, with highest MPs abundance in the hepatopancreas. The MPs accumulated in shrimp caused growth inhibition, abnormal swimming behavior and reduced swimming performance of L. vannamei. Following MPs exposure, oxidative stress and lipid peroxidation were also observed, which were strongly linked to attenuated swimming activity of L. vannamei. The above MPs-induced disruption in balance of antioxidant system triggered the hepatopancreatic damage in L. vannamei, which was exacerbated with increasing MPs concentrations (from 0.02 to 1 mg L^-1). Furthermore, metabolomics revealed that MPs exposure resulted in alterations of metabolic profiles and disturbed glycolysis, lipolysis and amino acid metabolism pathways in hepatopancreas of L. vannamei. This work confirms and expands the knowledge on the sublethal impacts and toxic modes of action of MPs in L. vannamei.

Detection methods of micro and nanoplastics

Plastics and related contaminants (including microplastics; MPs and nanoplastics; NPs) have become a serious global safety issue due to their overuse in many products and applications and their inadequate management, leading to possible leakage into the environment and eventually to the food chain and humans. There is a growing literature reporting on the occurrence of plastics, (MPs and NPs) in both marine and terrestrial organisms, with many indications about the harmful impact of these contaminants on plants and animals, as well as potential human health risks. The presence of MPs and NPs in many foods and beverages including seafood (especially finfish, crustaceans, bivalves, and cephalopods), fruits, vegetables, milk, wine and beer, meat, and table salts, has become popular research areas in recent years. Detection, identification, and quantification of MPs and NPs have been widely investigated using a wide range of traditional methods, such as visual and optical methods, scanning electron microscopy, and gas chromatography-mass spectrometry, but these methods are burdened with a number of limitations. In contrast, spectroscopic techniques, especially Fourier-transform infrared spectroscopy and Raman spectroscopy, and other emerging techniques, such as hyperspectral imaging are increasingly being applied due to their potential to enable rapid, non-destructive, and high-throughput analysis. Despite huge research efforts, there is still an overarching need to develop reliable analytical techniques with low cost and high efficiency. Mitigation of plastic pollution requires establishing standard and harmonized methods, adopting holistic approaches, and raising awareness and engaging the public and policymakers. Therefore, this chapter focuses mainly on identification and quantification techniques of MPs and NPs in different food matrices (mostly seafood).

Occurrence of nano/microplastics from wild and farmed edible species. Potential effects of exposure on human health

The occurrence of nano/microplastics (N/MPs) has become a global concern due to their risk on the aquatic environment, food webs and ecosystems, thus, potentially affecting human health. This chapter focuses on the most recent evidence about the occurrence of N/MPs in the most consumed wild and farmed edible species, the occurrence of N/MPs in humans, the potential impact of N/MPs on human health as well as future research recommendations for assessing N/MPs in wild and farmed edible species. Additionally, the N/MP particles in human biological samples, which include the standardization of methods for collection, characterization, and analysis of N/MPs that might allow evaluating the potential risk of the intake of N/MPs in human health, are discussed. Thus, the chapter consequently includes relevant information about the content of N/MPs of more than 60 edible species such as algae, sea cucumber, mussels, squids, crayfish, crabs, clams, and fishes.

A review of microplastic pollution in aquaculture: Sources, effects, removal strategies and prospects

As microplastic pollution has become an emerging environmental issue of global concern, microplastics in aquaculture have become a research hotspot. For environmental safety, economic efficiency and food safety considerations, a comprehensive understanding of microplastic pollution in aquaculture is necessary. This review outlines an overview of sources and effects of microplastics in aquaculture. External environmental inputs and aquaculture processes are sources of microplastics in aquaculture. Microplastics may release harmful additives and adsorb pollutants in aquaculture environment, cause deterioration of aquaculture environment, as well as cause toxicological effects, affect the behavior, growth and reproduction of aquaculture products, ultimately reducing the economic benefits of aquaculture. Microplastics entering the human body through aquaculture products also pose potential health risks at multiple levels. Microplastic pollution removal strategies used in aquaculture in various countries are also reviewed. Ecological interception and purification are considered to be effective methods. In addition, strengthening aquaculture management and improving fishing gear and packaging are also currently feasible solutions. As proactive measures, new portable microplastic monitoring system and remote sensing technology are considered to have broad application prospects. And it was encouraged to comprehensively strengthen the supervision of microplastic pollution in aquaculture through talent exchange and strengthening the construction of laws and regulations.

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.

Size-dependent toxicological effects of polystyrene microplastics in the shrimp Litopenaeus vannamei using a histomorphology, microbiome, and metabolic approach

Due to the wide application of plastic products in human life, microplastic pollution in water has recently attracted more attention. Many studies have revealed the size-dependent toxicity of microplastics. Here, we investigated the toxicological effects of polystyrene microplastics (PS-MPs) on the white leg shrimp, Litopenaeus vannamei, a profitable aquaculture species, using a comprehensive histomorphological, microbiome, and metabolomic approach to verify whether smaller particles are more toxic than larger particles. L. vannamei were experimentally exposed to water containing PS-MPs of four sizes (0.1, 1.0, 5.0, and 20.0 μm) for 24 h at 10 mg/L (acute experiment) and 12 d at 1 mg/L (subchronic experiment). After 24 h of acute exposure, PS-MP accumulation in shrimp indicated that the ingestion and egestion of PS-MPs had a size-dependent effect, and smaller particles were more bioavailable. The tissue morphological results of subchronic experiments showed that, for the guts and gills, the smaller sizes of the PS-MPs exhibited greater damage. In addition, 16 S rRNA gene amplicon sequencing showed that the alpha diversity was higher under larger PS-MP exposure. Correlated with changes in intestinal bacteria, we found a greater enrichment of metabolic pathways in hemolymph proteins and metabolites in larger PS-MP groups, such as "arginine and proline metabolism", "protein digestion and absorption", "lysine degradation". Interestingly, the activity or content of biomarkers of oxidative stress showed a peak at 1 μm and 5 μm. Under specific sizes of PS-MPs, the abundance of the pathogen Vibrio and probiotic bacteria Rhodobacter (5-μm) and Bacillus and Halomonas (1-μm) were simultaneously enriched. Our results indicated that PS-MP exposure can cause size-dependent damage to shrimp, yet specific particle size can be influential differently in regard to some research indicators. Therefore, it can enhance our comprehensive understanding of the impacts of microplastics on shrimp health and suggests that specific particle size should be considered when assessing the size-dependent toxicity of microplastics.

Polystyrene microplastics induced male reproductive toxicity and transgenerational effects in freshwater prawn

Microplastics have become pervasive environmental pollutants, especially in freshwater rivers and lakes. However, how freshwater prawns' reproductive system is affected by polystyrene microplastics (PS-MPs) remains incompletely understood. Thus, the present study aimed to determine the effect of PS-MPs on the male reproductive system and offspring larval immunity in oriental river prawn. Acute exposure to PS-MPs decreased the survival rate and heart rate of prawn larvae. After chronic exposure to PS-MPs (2 and 20 mg/L) for four weeks, the oxidative stress generation in testis tissue indicated a negative impact on male prawn testicular function. PS-MPs disrupted testicular germ cell quality and caused sex hormone imbalance, leading to reduced hatching success and survival of F1 larvae, despite not being exposed to PS-MPs. Steroidogenic gene expression was altered and apoptosis-related genes had higher expression in the gonads after parental exposure to PS-MPs. Decreased immunity-related enzyme activities were observed in F1 larvae with/without continued PS-MPs exposure, compared with those in untreated prawns. A concentration-dependent increase in bioaccumulation of PS-MPs in different tissues of larval offspring was observed. Thus, PS-MPs had multiple effects on male reproductive dysfunction and transgenerational toxicity in prawns. Our findings provide a novel insight into the reproductive toxicity mechanism of microplastics in freshwater crustaceans.

Microplastic contamination in wild shrimp Litopenaeus vannamei from the Huizache-Caimanero Coastal lagoon, SE Gulf of California

We identified and characterized microplastics (MPs) in the gastrointestinal tract (GT), gills (GI), and exoskeleton (EX) of Litopenaeus vannamei in a coastal lagoon from the SE Gulf of California. The most common MPs were fibers and fragments with an average size of 403 ± 296 μm, in which the transparent and blue colors predominated. The abundance (items/g as wet weight (ww)) in the GT, GI, and EX was 114.7 ± 33.2, 13.7 ± 5.3 and 3.0 ± 0.5, respectively. The abundance of MPs per shrimp was 13.3 ± 1.1, while the abundance per individual (ww) was 0.9 ± 0.2 MPs/g. Considering the consumption of shrimp in Mexico, MP abundance, and shrimp consumption (discarding GI and EX), we estimated MP ingestion as 280 items/person/year. The results from this study can be used as background information for future MP biomonitoring in shrimp species of ecological and commercial importance.