Number Of Microplastics Research Articles

Delving into river health: unveiling microplastic intrusion and heavy metal contamination in freshwater

The persistent use of plastics in chemical and industrial procedures has resulted in the contamination of the environment and human health via microplastics (MPs). This study investigates heavy metals, MP, pH, conductivity, and turbidity levels in the Nida River in Poland. The Nida River exhibited the existence of diverse coloured MPs in several physical forms, including fibres, fragments, pellets, and foams. Differences in the number of MPs were noted at five selected locations, with values ranging from 215 to 280 MPs per litre. The mean number of MPs observed was 245 ± 21 per litre. The study of water samples using a scanning electron microscope indicates the existence of various MPs. The morphological study of these MPs revealed patterns of degradation. The energy-dispersive X-ray examination indicates the existence of several elements, such as carbon, nitrogen, oxygen, sodium, magnesium, aluminium, silicon, phosphorus, and others. The water exhibited fluctuations in its levels of heavy metal content. The average zinc concentration in all samples was 96.86 ± 40.25 μg/L, which was the highest. It was followed by Pb 37.6 ± 31.9 μg/L concentration. The turbidity measurement was recorded as 46.38 ± 22.54, the pH level was 7.078 ± 0.33, and the conductivity value was determined to be 1338.8 ± 39.64. The HQ and HI values for adults and children in all age groups were less than one. The carcinogenic excess lifetime cancer risk (ELCR) exceeds the threshold value in most water samples. This study aims to fill the existing gap in understanding the precise measurement of MPs and heavy metals in freshwater sources in Poland. Health risk evaluations are the first step in developing pollution management, control, and water quality standards.Graphical

Impact of heteroaggregation between microplastics and algae on particle vertical transport

Understanding the impacts of microplastics (MPs) on aqueous environments requires understanding their transport dynamics and how their presence affects other natural processes and cycles. In this context, one aspect to consider is how MPs interact with freshwater snow (FWS), a mixture of algae and natural particles. FWS is one of the primary drivers of the flux of organic matter from the water surface to the bottom sediment, where zooplankton, diurnal migration, fish faecal pellets settling and turbulent mixing can also play prominent roles. Understanding how MPs and FWS heteroaggregation affects their respective settling velocities is important to assess not only MPs fate and transport but also their ecological impacts by altering FWS deposition and thereby nutrient cycling. In this present study, we obtained a mechanistic understanding of the processes controlling MPs settling dynamics and heteroaggregation with FWS and the subsequent impacts on the settling rates of both MPs and ballasted FWS. Here we used a plexiglass column equipped with a stereoscopic camera system to track the settling velocities of (1) MPs of various compositions, densities and morphologies, (2) FWS flocs and (3) MP–FWS agglomerates. For each experimental set, thousands of particles were tracked over a series of image sequences. We found that agglomerates with high-density MPs settled at least twofold faster than FWS alone, implying a much smaller residence time in the water column, except for cases with MP fibres or low-density plastics. These findings will help to refine MP fate models and, while contingent on MPs number, may impact biogeochemical cycles by changing the flux of nutrients contained in FWS to the sediment.

Vertical transfer of microplastics in nearshore water by cultured filter-feeding oysters

Microplastics (MPs) are widely distributed in the sea, but the vertical transfer of MPs by marine organisms in coastal area is still poorly understood. In this study, we used laser direct infrared (LDIR) spectroscopy to determine the number and characteristics of MPs deposited by cultured oyster Crassostrea gigas and further compared the differences between MPs of natural deposit and biodeposit in field environments. The amounts of MPs found in the biodeposit of cultured oysters were 3.54 times greater than that in the natural deposition. The polymer types of biodeposit MPs also differed from those of natural deposition. It was estimated that a single oyster can deposit 15.88 MPs per day, which is a figure much higher than the initial results, and hotspots of MPs deposition may be formed within the oyster aquaculture area. We used generalized linear mixed model (GLMM) to further infer the sources of MPs in sediments and found that distance to shore, cultured zone and urban center were important predictors of MPs abundance in sediments of aquaculture area. The above results suggest that cultured bivalves have an important capacity for MPs biodeposition and will further change the vertical distribution pattern of MPs in coastal environments.

Effects of food quantity on the ingestion and egestion of MPs with different colors by Daphnia magna

Aquatic organism uptake and accumulate microplastics (MPs) through various pathways, with ingestion alongside food being one of the primary routes. However, the impact of food concentration on the accumulation of different types of MPs, particularly across various colors, remains largely unexplored. To address this gap, we selected Daphnia magna as a model organism to study the ingestion/egestion kinetics and the preference for different MP colors under varying concentrations of Chlorella vulgaris. Our findings revealed that as the concentration of Chlorella increased, the ingestion of MPs by D. magna initially increased and then showed a decline. During the egestion phase within clean medium without further food supply, an increase in food concentration during the ingestion phase led to a slower rate of MP discharge; while when food was present during the egestion phase, the discharge rate accelerated for all treatments, indicating the importance of food ingestion/digestion process on the MPs bioaccumulation. Furthermore, in the presence of phytoplankton, D. magna demonstrated a preference for ingesting green-colored MPs, especially at low and medium level Chlorella supply, possibly due to the enhanced food searching activities. Beyond gut passage, we also examined the attachment of MPs to the organism's body surface, finding that the number of adhered MPs increased with increasing food concentration, likely due to the intensified filtering current during food ingestion. In summary, this study demonstrated that under aquatic environment with increasing phytoplankton concentrations, the ingestion and egestion rates, color preferences, as well as surface adherence of MPs to filter feeding zooplanktons will be significantly influenced, which may further pose ecological risks. Our results offer novel insights into the unintentional accumulation of MPs by zooplankton, highlighting the complex interactions between food availability and MPs accumulation dynamics.

Abundances and characteristics of microplastics in core sediments of the Persian Gulf coast, Iran

The presence of microplastics in tidal sediments is a growing ecotoxicological concern for sea and benthic health. This investigation was designed to record and characterize the vertical prevalence of microplastics (MPs) in intertidal sediments of the Persian Gulf (around Bushehr city, Iran). Sediments of three depths (0-10 cm, 10-20 cm, and 20-30 cm) were sampled during low tide in six sites along the coastal zone of Bushehr, Iran. MP particles were found in all evaluated areas and sediment depths. The average abundance of MPs in all of the sediment samples was 117.96 ± 97.75 particles kg−1 dry sediment. No differences were found in the MPs number among the sites. The most dominant microplastics in surface sediments were 2-5 mm in size. In all areas, fibers and fragments were more abundant. Particles in higher depths (0-10 cm) were often colorless (white, and transparent). Raman spectroscopy indicated the presence of polystyrene, polyethylene, polyvinyl chloride, polyethylene terephthalate, and polypropylene in the samples. Further research is required to evaluate the possible interaction between MPs and layers of sediments. Waste management and proper wastewater disposal are critical to control MPs pollution in intertidal ecosystems around coastal cities.

Trophic transfer, bioaccumulation and translocation of microplastics in an international listed wetland on the Montreux record

Microplastics (MPs) are concerning emerging pollutants. Here, MPs in four edible aquatic species of different trophic levels (between ∼2 and 4), including fish species Esox lucius (Esocidae: Esocinae); Cyprinus carpio (Cyprinidae: Cyprininae); and Luciobarbus caspius (Cyprinidae: Barbinae); and the swan mussel Anodonta cygnea (Unionidae), were assessed in the Anzali freshwater ecosystem. It is a listed wetland in the Montreux record. MPs were extracted from gastrointestinal tracts (GI), gills, muscles, and skin. All the studied fish and mussels (n = 33) had MPs. MP fibres, fragments and sheets were detected in every GI examined, however, fibres were the only type of MPs in skins, muscles and gills and were the most abundant MP. The MPs found in the fish and mussels were mainly made of nylon (35% of the total MPs), polypropylene-low density polyethylene (30%), and polycarbonate (25%). The average numbers of MPs found in every fish specimen, expressed per wet body mass, had a moderate negative correlation with the condition factor (K) (MP/g - K: Pearson correlation r = −0.413, p = 0.049), and there was no significant relation with the growth factor (b) (r = −0.376; p = 0.068). Importantly, Luciobarbus caspius (with trophic level 2.7–2.8) bioaccumulated MPs and presented a strong correlation between their MP contamination and age (r = 0.916 p < 0.05). Greater gill mass (or related factors) played an important role in the accumulation of MPs, and there was a strong correlation between these factors for Esox lucius and Cyprinus carpio (r = 0.876; r = 0.846; p < 0.05 respectively). The highest MP/g gills (1.91 ± 2.65) were in the filter feeder Anodonta cygnea inhabiting the benthic zone. Esox lucius (piscivorous, trophic level 4.1) was the most contaminated species overall (a total of 83 MPs in 8 individuals, with 0.92 MP/g fish), and their gills where MPs mainly accumulated. Cyprinus carpio was the most contaminated specimen (MPs in specimens), while the number of MPs per mass unit increased with the trophic level. Their feeding and ecological behavior in the aquatic habitat affected the level of accumulation. This work includes evidence of translocation of MPs within the aquatic organisms.

Microplastic Release from Single-Use Plastic Beverage Cups.

Microplastics (MPs) have attracted considerable attention as one of the most remarkable food and drink pollutants in recent years. Disposable cups, which are widely used as single-use containers, have been suspected as the primary sources of MPs found in cold and hot beverages. In this study, the effect of different exposure times (0, 5, 10 and 20 min) and temperatures (4 °C, 50 °C and 80 °C) on MP release from the single-use cups made of four different materials [polypropylene (PP), polystyrene (PS), polyethylene (PE) coated paper cups and expanded polystyrene (EPS)] into the water was investigated. The number of MPs ranged from 126 p/L to 1420 p/L, while the highest and lowest counts were observed in the PP (50 °C for 20 min) and PE-coated paper cups (4 °C 0 min), respectively. Washing the cups with ultrapure water prior to use reduced the MP release by 52-65%. SEM images demonstrated the abrasion on the surface of the disposable cups as a result of hot water exposure. Intensities of FTIR absorbance levels at some wavelengths were decreased by the water treatment, which could be evidence of surface abrasion. The annual MP exposure of consumers was calculated as 18,720-73,840 by the consumption of hot and cold beverages in disposable cups. In conclusion, as the level and potential toxicity of MP exposure in humans are not yet fully known, this study sheds light on the number of MPs transferred to cold and hot beverages from single-use disposable cups.

Determination of Microplastics in Omega-3 Oil Supplements.

Microplastics (MPs) are ubiquitous in the environment, posing a threat to ecosystems and causing increasing concerns regarding their impacts on the human body through exposure. However, there has been limited research on the presence of MPs in functional foods, despite them being consumed for health improvement. This study aimed to investigate MP occurrence in various omega-3 oils and oil products in the Korean market and its relation to the source of raw material or manufacture. MPs were investigated in omega-3 capsules and raw oil, sourced from both plant-based (PB) and animal-based (AB) sources. We developed a method of direct filtration with acetone washing for collecting and characterizing MPs larger than 5 μm using micro-Raman spectroscopy. The average number of MPs by mass was found to be 1.2 ± 1.7 MPs/g for PB raw oil, 2.2 ± 1.7 MPs/g for AB raw oil, 3.5 ± 3.9 MPs/g for PB capsule oil, and 10.6 ± 8.9 MPs/g for AB capsule oil. Polypropylene and polyethylene terephthalate were the major MP species (83-95%) found in omega-3 oil. The proportions based on size range remained consistent across all groups, with a trend of being detected at higher rates as the size decreased. The results reveal that the main reason for the MP contamination of omega-3 oil is not the source of raw material but the manufacturing and packaging process.

Asian clam Corbicula fluminea as potential biomonitor of microplastics and metal(oid)s in a Patagonian River

This study summarizes the concentration in dry weight (dw) of several metal(oid)s (As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn), as well as the abundance and characteristics of microplastics (MP) in wet weight (ww) of the soft tissues of clam Corbicula fluminea from Chubut River (Patagonia, Argentina). The contents of essential elements were in the following decreasing order: Zn > Mn > Cu > Ni; meanwhile, non-essential elements Cd, Cr and Pb were below the detection limit (<0.5 μg/g dw). A high mean concentration of As (6.1 ± 0.3 μg/g dw) was found, surpassing the maximum allowable limit established by the Argentine Food Code for bivalve molluscs. The number of MP ranged from 0.07 to 1.27 items/ind. and from 0.2 to 2.9 items/g ww. Fibers were the most common shape, mainly transparent. The size of MP ranged from 42 to 1917 μm, accounting for 62 % of MP between 50 and 450 μm. The dominant polymer was PET based on the results of Raman spectroscopy. Based on the widespread distribution of MP in the environment and the wide range of effects on organisms, it is necessary to develop long-term monitoring programs for MP contamination in different environmental matrices. Understanding the bioaccumulation of MP in bivalves is crucial to assess the potential risk to human health through consumption and to the ecosystem. We propose that the widespread Asian clam could serve as a useful biomonitor for MP and As pollution in freshwater and estuarine environments such as the Chubut River.

The distribution of sediment microplastics assemblages is driven by location and hydrodynamics, not sediment characteristics, in the Gulf of Maine, USA

Microplastics (MP) are found in marine sediments across the globe, but we are just beginning to understand their spatial distribution and assemblages. In this study, we quantified MP in Gulf of Maine, USA sediments. MP were extracted from 20 sediment samples, followed by polymer identification using Raman spectroscopy. We detected 27 polymer types and 1929 MP kg−1 wet sediment, on average. Statistical analyses showed that habitat, hydrodynamics, and station proximity were more important drivers of MP assemblages than land use or sediment characteristics. Stations closer to one another were more similar in their MP assemblages, tidal rivers had higher numbers of unique plastic polymers than open water or embayment stations, and stations closer to shore had higher numbers of MP. There was little evidence of relationships between MP assemblages and land use, sediment texture, total organic carbon, or contaminants.

Evaluation of microplastic pollution using bee colonies: An exploration of various sampling methodologies

Recent research has highlighted the potential of honeybees and bee products as biological samplers for monitoring xenobiotic pollutants. However, the effectiveness of these biological samplers in tracking microplastics (MPs) has not yet been explored. This study evaluates several methods of sampling MPs, using honeybees, pollen, and a novel in-hive passive sampler named the APITrap. The collected samples were characterized using a stereomicroscopy to count and categorise MPs by morphology, colour, and type. To chemical identification, a micro-Fourier transform-infrared (FTIR) spectroscopy was employed to determine the polymer types. The study was conducted across four consecutive surveillance programmes, in five different apiaries in Denmark. Our findings indicated that APITrap demonstrated better reproducibility, with a lower variation in results of 39%, compared to 111% for honeybee samples and 97% for pollen samples. Furthermore, the use of APITrap has no negative impact on bees and can be easily applied in successive samplings. The average number of MPs detected in the four monitoring studies ranged from 39 to 67 in the APITrap, 6 to 9 in honeybee samples, and 6 to 11 in pollen samples. Fibres were the most frequently found, accounting for an average of 91% of the total MPs detected in the APITrap, and similar values for fragments (5%) and films (4%). The MPs were predominantly coloured black, blue, green and red. Spectroscopy analysis confirmed the presence of up to five different synthetic polymers. Polyethylene terephthalate (PET) was the most common in case of fibres and similarly to polypropylene (PP), polyethylene (PE), polyacrylonitrile (PAN) and polyamide (PA) in non fibrous MPs. This study, based on citizen science and supported by beekeepers, highlights the potential of MPs to accumulate in beehives. It also shows that the APITrap provides a highly reliable and comprehensive approach for sampling in large-scale monitoring studies.

Microplastics and Nano-plastics Contamination in Foods: Current Understanding of the Health Impact on Human and Potential Solutions

Plastics released into the environment can be degraded by physical erosion, biodegradation, photocatalytic activity, and oxidation, resulting in smaller plastics particles. Microplastics (MPs) are plastic particles relatively smaller than 5 mm in size. Furthermore, microplastics with particle sizes less than 1000 or 100 nm are known as nano-plastics (NPs). The presence and effect of MPs and NPs in human body has not been adequately studies, thus we aim to explain the origins of MPs and NPs adept, carefully explore the pathways by which MPs and NPs enter the body system and highlight the impact of MPs and NPs on human health. Major examples include Polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyamide (PA), polystyrene (PS), polyethylene terephthalate (PET), Acrylonitrile-Butadiene-Styrene (ABS), and polymethyl methacrylate (PMMA). MPs and NPs were found to have two sources (primary and secondary). The primary sources are materials purposely produced to suit household and industrial uses, such as exfoliants for skin care products, construction, and packaging materials. Secondary sources originated from the decomposition/degradation of large plastic products over time. Plastics were found in plants (fruits and vegetables), animals (fish, crab, shrimp, oysters, and mussels), water (taps, sachet, and bottled water), salt, sugar, and honey. Plastics' impact on the human ecosystem is getting increasingly severe, and it is imperative that proper attention be paid to this issue. The vast number of MPs and NPs available can influence the lives of the populace in each geographic area. In this review article, we identified three routes through which MPs and NPs gain entrance into the human body: oral ingestion, cutaneous (skin contact), and inhalation. Furthermore, we investigated and summarized the impacts of MPs and NPs on human health. The most impacted organs in the body included the lungs, blood, kidney, brain, ovary, testes, and intestines. In this review, we offered a viable solution that includes the use of biodegradable polymers, increased usage of eco-friendly biotechnology and engineering solutions, and the implementation of regulatory measures. In future, we intend to investigate the bioaccumulation and effect of MPs/NPs on human health.

Pollution and health risk assessment of co-existing microplastics and heavy metals in urban dust of Riyadh city, Saudi Arabia

Microplastics (MPs) and heavy metals have recently attracted much attention due to their widespread distribution in the environment. Co-occurrence of MPs and heavy metals in dust poses potential health risks for humans. The objectives of this study were to investigate pollution and health risk factors associated with co-occurring MPs and heavy metals in urban dust. Here, 20 dust samples (both indoor and outdoor environments) were collected from different places in Riyadh, Saudi Arabia using sweeping method. The MPs were separated from dust samples via density separation using ZnCl2 Microscopic techniques were used to investigate MPs while inductively coupled plasma optical emission spectrometry was used heavy metals analyses in the collected samples. The results of the study showed that all the collected dust samples were contaminated with MPs of different shapes, sizes, and colors. Fragment-shaped MPs were the most dominant, followed by granules, fibers, and lines, while the majority of the MP particles were red and black. Furthermore, the size distribution analyses demonstrated that particles above 1,000 µm were abundant. Also, the number of MPs was in the range of 20 particles g-1 to 1,052 particles g-1. Human exposure estimations showed that toddlers could inhale more MPs (0.86 MPs particles kg-1 day-1 and 312.93 particles kg-1 year-1) than children, teenagers, and adults. In addition, the concentrations of heavy metals varied from one site to another, however, the average concentrations were lower than their corresponding values in the guidelines (except for Zn). The integrated potential ecological risk in dust samples was characterized as a low-risk criterion. The enrichment factor for Zn in dust samples at all sites was more than 2, indicating a major contamination concern and anthropogenic sources responsible for the existence of Zn. The estimated hazard quotient indicates that children and adults are saved from the adverse effects of dust inhalation in the studied area. These findings could serve as a preliminary step for efficient pollution management and environmental quality maintenance in Riyadh.

Presence of Microplastic in Erzurum Urban Wastewater Treatment Plant

The rapid increase in the number of microplastics (MPs) in aquatic environments reveals the risk of increasing their harmful effects on living life. MPs, especially those with smaller particle sizes, are very difficult to detect and measure when they reach the aquatic environment. This study investigated the presence of microplastics at the entrance and exit points of the Erzurum Urban Wastewater Treatment Plant. The results showed that the average number of MPs in the influent and effluent was 36400 MP/m3 and 2875 MP/m3, respectively. Primary and secondary treatment processes cannot provide high removal efficiencies in removing MPs from wastewater. However, in WWTPs where tertiary treatment is carried out, as in the WWTP examined, the removal efficiency exceeds 90%.

Review: Impact of microfluidic cell and particle separation techniques on microplastic removal strategies

This review highlights the growing concern regarding the proliferation of microplastics (MPs) in aquatic ecosystems and their potential impact on both the environment and human health. Despite current efforts, a considerable number of MPs remain untreated due to their small size. Conventional identification and treatment methods are summarized pointing to the current limitations. Emerging technologies in microfluidics and nanotechnology are presented as potential solutions for the removal of MPs from aquatic environments. These novel technologies, which are currently being used for the development of novel point of care (PoC) diagnostic devices, can take advantage of the size and density similarities between MPs and commonly separated particles in microfluidics applications such as cells, making them promising candidates for MPs separation and recovery in wastewater treatment plants.This review evaluates the limitations of current MPs separation and recovery technologies in water treatment plants and laboratories and compares them with the promising capabilities of microfluidics and nanotechnology, providing valuable insights into future strategies for combating MPs pollution.

Microplastics in the Danube River and Its Main Tributaries—Ingestion by Freshwater Macroinvertebrates

This study was carried out at the Danube River and its tributaries during the Joint Danube Survey 4 (JDS4) expedition. Three freshwater benthic species were used to estimate the quantity of microplastics (MPs): Corbicula spp., Limnodrilus hoffmeisteri (Claparede, 1862), and Polypedilum nubeculosum (Meigen, 1804). Following the kick and sweep technique, individuals were sampled using a hand net or dredge. In order to estimate the number of MP particles/individual particles/g wet body mass, the body mass and total length of all specimens were measured. Alkaline (Corbicula spp. and L. hoffmaisteri) and enzymatic (P. nubeculosum) protocols were performed for tissue degradation. All samples were filtered through glass microfiber filters (mesh size 0.5 µm). The particles were photographed, measured, and counted. A total of 1904, 169, and 204 MPs were isolated from Corbicula spp., L. hoffmaisteri, and P. nubeculosum, respectively. To confirm the chemical composition of isolated MPs, a subsample of 46 particles of the fragmented particles from 14 sampling sites was analysed via µ-ATR-FTIR spectroscopy analysis. The particles were characterised as polycarbonate (PC), polyethylene terephthalate (PET), polypropylene–polyethylene copolymer (PP-PE), nylon (polyamide-PA) and cellophane, with the domination of PET.

Characterization of the intestinal transport mechanism of polystyrene microplastics (MPs) and the potential inhibitory effect of green tea extracts on MPs intestinal absorption

The aims of the current study included characterizing the intestinal transport mechanism of polystyrene microplastics (MPs) with different charges and sizes in the intestinal epithelial cell model and determining the inhibitory effect of green tea extracts (GTEs) on the intestinal absorption of MPs in Caco-2 cells. The smaller sizes, which included diameters of 0.2 μm, of amine-modified MPs compared to either larger size (1 μm diameter, or carboxylate-MPs (0.2 and 1 μm diameter) significantly lowered the cell viability of caco-2 cells that were measured by MTT assay (p < 0.05). The transported amount (particles/mL of the cell media) of amine-modified MPs by the Caco-2 cell, was not dependent according to the concentrations, energy, or temperature, but it was higher than the carboxylate-modified MPs. The co-treatment of GTEs with the amine-modified MPs inhibited Caco-2 cell cytotoxicity as well as reduced the production of intracellular reactive oxygen species (ROS) in HepG2 generated by the exposure of amine-modified MPs. The GTEs co-treatment also increased trans-epithelial electrical resistances (TEER) and reduced the transportation of Lucifer Yellow via the Caco-2 monolayer compared to only the amine-modified MPs exposure. The GTEs treatment led to a decrease in the number of amine-modified MPs transported to the basal side of the Caco-2 monolayer. The results from our study suggest that the consumption of GTEs could enhance the intestinal barrier function by recovering intestinal epithelial cell damage induced by MPs, which resulted in a decrease of the intestinal absorption of MPs.

Uncovering microplastics contamination in canned seafood

There is limited research on the occurrence of microplastics (MPs) in canned seafood. All types of canned seafood investigated in the present study were contaminated. After sample digestion in 30 % hydrogen peroxide, a total of 40 MPs were recovered. Fibers were the most common type, blue was the dominant colour, and Fourier Transform Infrared Spectroscopy (FTIR) identified polyester as the most common polymer. Considering all samples, an average of 3.5 ± 5.2 MPs/can was obtained, with octopus in tomato sauce and tuna in olive oil presenting the highest contamination (5.2 ± 7.5 MPs/can and 5.2 ± 5.1 MPs/can, respectively). Also, significant differences between the number of MPs in the seafood tissues and immersion liquids were verified. The present study demonstrates MPs occurrence in canned seafood, a potential contamination pathway for humans. More research on the different stages of the canning processing is vital for understanding MPs contamination in cans.

Occurrence of microplastics in fish gastrointestinal tracts belongs to different feeding habits from the Bangladesh coast of the Bay of Bengal.

The Bay of Bengal (BoB) is home to a range of commercially important species with different food habits and feeding features. Microplastic (MP) contamination in the fish of BoB, like in many other marine environments, is a significant environmental concern. The study aimed to investigate the presence of microplastics (MPs) in the gastrointestinal tracts (GITs) of selected commercial marine fishes from the Bangladesh coast of the BoB. Six fish species (Escualosa thoracata, Tenualosa ilisha, Johnius belangerii, Trichiurus lepturus, Planiliza parsia, and Mystus gulio) were investigated (n = 120) following hydrogen peroxide digestion, and floatation (saline solution) protocols. After analyses, a total number of 696 MPs (dimension 0.3 to 5 mm) were identified. Moreover, the highest occurrence of MPs in fish GITs was found in planktivorous fish (average of 7.7 items/individual), followed by omnivorous (average of 5.2 items/individual), and carnivorous fish (average of 4.6 items/individual) (p < 0.001). However, planktivorous E. thoracata showed the highest number of MPs per g of GIT (average of 30.99 items/g GIT), whereas T. ilisha showed the lowest count (average of 0.77 items/g GIT). Different types of MPs (fibers (19 to 76%), fragments (6 to 61%), films (8 to 35%), microbeads (0 to 5%), and foams (0 to 2%)) were also observed. In terms of the color of MPs, the transparent, black, green, and blue types were the most common. Polymers were found as polyethylene (35 to 43%), polyethylene terephthalate (28 to 35%), polyamide (20 to 31%), and polystyrene (0 to 7%). The study provides a significant incidence of MPs in fish from the Bangladesh part of the BoB, which is very concerning. Therefore, long-term research is indispensable to ascertain the variables affecting the presence of MPs in fish, their origins, and their potential effects on the BoB fisheries. Stringent policies on plastic use and disposal should be strongly urged in this coastal region.

A Review of Microplastic Identification and Characterization Methods in Aquatic Environments

Plastic waste has become a major global issue, with over 390.7 million tons of plastic produced in 2021. Because of its durability, low recycling rates, poor waste management, and maritime use, a considerable portion of plastic waste ends up in aquatic environments. Photo-oxidation and other mechanisms degrade plastics into microplastics (MPs), which are particles smaller than 5 mm. MPs can spread through the aerial, terrestrial, and aquatic areas, and running waterways serve as conduits for MP transport across various ecosystems. MPs have been found at various levels of the food web, and animals can ingest, inhale, or absorb them through their skin. MPs pose a significant health risk to flora and fauna, including marine creatures and humans, due to their small size, diverse colors, high abundance, and ability to adsorb antibiotic-resistant pathogens, causing cytotoxicity, acute reactions, undesirable immunological responses, neurotoxicity, and DNA alteration. MPs have a negative economic impact on industries such as agriculture, fishing, tourism, etc. Detecting and quantifying the presence of MPs is therefore critical. The purpose of this paper is to provide an overview of the various techniques and equipment used to detect and characterize MPs in aqueous environments. Identifying and educating the public about the primary sources of plastic pollution can help reduce the number of MPs in the environment.