Microplastic Ingestion Research Articles

Microplastics and gut microbiomes impact on Yunnan snub-nosed monkeys in the Three Parallel Rivers region in China.

Microplastics (MPs) has been rapidly increasing and interacting with wildlife. As the highest altitudes inhabited non-human primate, Yunnan snub-nosed monkey (Rhinopithecus bieti) have been proven to be an umbrella and flagship species to indicate ecosystem changes and help develop environmental management strategies. In this study, we aimed to investigate the behavioral and ecological reasons for the types, content and differences of MPs in the feces of R. bieti, and explored the effects of MPs on gut microbiome of R. bieti. We used the Agilent 8700 LDIR to identify the abundance and size distribution of MPs in fecal samples, and then analyzed the causes of differences in MPs content by combining data from different populations (wild group, provisioned wild group) and dominance hierarchy. At the same times, the relationships were investigated between gut microbiome diversity and MPs content. We first demonstrate MPs ingestion by R. bieti, which highlights the potential impacts of MPs pollution in such high-altitude, inaccessible protected areas. A total of 36 types of MPs were detected, with an average of 75.263 ± 58.141MPs/g. Food provisioning and tourism significantly increased the content of MPs in the feces of R. bieti, but tourism alone did not significantly increase the content of MPs as food provisioning. At the same time, the study found that there was no significant difference in the content of MPs between different sex groups, however, the feces MPs content of adult R. bieti was significantly lower than that of juvenile, and the social dominance hierarchies among OMUs was positively correlated with the exposure of MPs. The current level of MPs pollution did not cause gut microbiome dysbiosis of R. bieti. Our study proved from behavioral and ecological perspectives that the R. bieti exposure to MPs was related to provisioned food, and was closely related to dominance hierarchy and age. From the perspective of intestinal microbiology, it was proved that the current intake of MPs did not cause gut microbiome dysbiosis of R. bieti. Our study provided scientific basis for formulating effective protection measures and promoting the effective protection of rare and endangered animals.

Microplastics in honey from Türkiye: Occurrence, characteristic, human exposure, and risk assessment

In this study, honey samples produced in Türkiye in 2023 were analyzed to assess occurrence of microplastics. The microplastics were physically and chemically characterised by stereomicroscope and FT-IR, respectively. Microplastic exposure by honey consumption was also calculated and risk assessment was done. The mean microplastic concentration was 314±353 (0–1280) particles/kg in 32 honey samples analyzed. The microplastics with four different polymers (EVA, PE, PP, and Nylon–6), two different shapes (fiber and fragment), and six different colors (black, brown, green, red, yellow, and transparent) were detected. The daily microplastic intake by consumption of monofloral and multifloral honey was calculated as 1.20 and 0.85 particles/day, respectively. The mean polymer hazard index and microplastic load index levels for all honey samples analyzed were 16.7±16 and 6.70±1.0, respectively. Result of this study confirmed that honey in Türkiye was contaminated with variety of microplastics. Considering to potential health risks of microplastics and associated chemicals to human health, production process should be improved by producers and urgent strategies and controls should be developed and applied by decision makers to eliminate the intake of microplastics through food.

First Evidence of Microplastic Ingestion by Riverine Fish From the Freshwater of Northwest Peninsular Malaysia.

In a baseline study, we investigated microplastic contamination in fish from the Pinang and Kerian Rivers in Northwest Peninsular Malaysia. In recognition of the growing concern over microplastic pollution in aquatic environments, we aimed to assess the abundance and characteristics of microplastics ingested by various fish species. Fish samples were collected from local fishermen, followed by a digestion process using 10% potassium hydroxide (KOH). Microplastics were isolated and analyzed through visual examination and attenuated total reflectance Fourier transform infrared spectroscopy. The results revealed a high prevalence of microplastics, with Johnius borneensis and Oreochromis sp. exhibiting the highest abundance, averaging 48.6 and 42.8 microplastics/g, respectively. The predominant shapes were fibers (55.6%) and fragments (25.9%), with colors primarily transparent (48.19%) and black (30.12%). Our results indicate significant contamination levels in freshwater fish, emphasizing the need for further research and effective mitigation strategies. These findings provide crucial baseline data on microplastics in Malaysian freshwater ecosystems. Environ Toxicol Chem 2024;43:2189-2198. © 2024 SETAC.

Increasing microplastic exposure had minimal effects on fatty acid composition in zooplankton and yellow perch in a large, in-lake mesocosm experiment

Using 10 m diameter mesocosms in a Canadian boreal lake, we investigated the effects of microplastic (MP) exposure on the body weight and diet of yellow perch ( Perca flavescens) and the fatty acid composition of yellow perch and zooplankton. We exposed the aquatic ecosystem within seven mesocosms for 10 weeks to a mixture of polyethylene, polystyrene, and polyethylene terephthalate fragments, ranging in nominal addition concentrations from 6 to 29 240 particles L−1 (although realized water column concentrations were lower), as well as two negative controls. Increasing MP exposure did not affect yellow perch body weight (growth) or diet, or the overall fatty acid composition of yellow perch muscle or zooplankton. Results were highly variable across mesocosms. Despite high levels of MP ingestion by yellow perch, we did not find evidence of MPs leading to food dilution or any other effect where we could anticipate impacts on food web structure.

Effect of alternative natural diet on microplastic ingestion, functional responses and trophic transfer in a tri-trophic coastal pelagic food web

The patchy distribution of microplastics (MP) and their size range similar to planktonic organisms, are likely to have major ecological consequences, through MP ingestion, food dilution, and transfer across trophic levels. Our study applied a community module using tritrophic food chain with zooplankton as prey, and a planktivorous seabass fry as predator. We conducted a series of feeding experiments and recorded the direct uptake of MP under six different concentrations ranging from 25 to 800 particles L−1. We also estimated the indirect transfer of MP via trophic link. The ingestion rates for Brachionus plicatilis, Mesocyclops isabellae, and Lates calcarifer, were 3.7 ± 0.3 MP ind−1 min−1, 1.69 ± 0.1 MP ind−1 min−1, and 3.51 ± 0.52 MP ind−1 h−1, respectively. In the presence of a natural diet, rotifers and copepods ingested significantly lower number, whereas, fish fry ingested a higher number of MP, suggesting further vulnerability to the consumers of MP-contaminated fish and potential biomagnification at higher trophic levels. Overall, the MP uptake rate increased with increasing concentration, and finally leveled off, indicating a type II functional response to MP concentration. The presence of natural diet led to a lower Km value. In the indirect transfer experiment, 74 % of B. plicatilis and 78 % of M. isabellae individuals were contaminated with MP, when offered as prey. Brachionid mastax and MP particles were observed in the gut of copepods. The fish fry gut content also recorded brachionid mastax, MP-contaminated copepods, and MP particles, showing direct evidence of trophic transfer pointing to a cascading effect on higher trophic levels including humans via piscivory.

Quantification and characterization of microplastics ingested by mangrove oysters across West Africa

Microplastic ingestion by marine organisms presents a challenge to both ecosystem functioning and human health. We characterized microplastic abundance, shape, size, and polymer types ingested by the West African mangrove oyster, Crassostrea tulipa (Lamarck, 1819) sampled from estuaries and lagoons from the Gambia, Sierra Leone, Ghana, Benin, and Nigeria using optical microscopy and Fourier transform infrared (FTIR) techniques. A total of 780 microplastics were isolated in the whole tissues of the 250 oysters (n = 50 oysters per country). The abundance and distribution of microplastics in the oysters followed the pattern: the Gambia > Ghana > Sierra Leone > Nigeria > Benin. The Tanbi wetlands in the Gambia recorded the highest average of 10.50 ± 6.69 per oyster while the Ouidah lagoon in Benin recorded the lowest average of 1.80 ± 1.90 per oyster. Overall, microplastic numbers varied significantly (p < 0.05) among the five countries. Microfibers, particularly those within 1001–5000 μm size, dominated the total microplastic count with a few fragments and films. No spherical microplastics were isolated in the oysters. In the Sierra Leone and Benin oysters, fragments and films were absent in the samples. Microplastic between the 1001 and 5000 μm size class dominated the counts, followed by 501–1000 μm, 101–500 μm, and 51–100 μm. Five polymer groups namely polyethylene, polyester, nylon, polypropylene, and polyamide were identified across the five countries, with polyethylene occurring in oysters from all five countries and polyester occurring in all but the oysters from Nigeria. This diversity of polymers suggests varied sources of microplastics ingested by the studied oysters. The absence of microspheres across the five supports findings from other studies that they are the least ingested and highly egested by the oysters.Graphical

Analysis of microplastics in the reuse of compost in three agricultural sites (Cádiz, Spain) as a circular economy strategy: detection of micropollutants and incidence of plastic ingestion levels by annelids

The system of fertilizing agricultural soils with sludge or compost from wastewater treatment processes, as one of the principles of the circular economy, can lead to microplastic (MP) contamination. The existing technical standards for fertilization are very recent and do not consider this problem, although there is scientific evidence of their existence. Therefore, this study, on the one hand, evaluates the presence of MPs in agricultural soils, previously treated with sludge or compost from wastewater treatment plants for fertilization, and on the second hand, it studies the effect of these MPs on earthworms in three different locations in the south of Spain. For the study, selected composts deriving from the different stages of the composting process and three fertilized soils with increasing MP doses were followed. Samples were taken from different sections in depth (0–5, 5–10, and 10–20 cm) to study the shape, size, type, and abundance of MPs using infrared spectroscopy (FTIR). The results showed that the most abundant shape was fiber, followed by fragment and finally bulk, for both composts and soils. Regarding size distribution, 100 µm was the predominant size in composts (64.3% ± 9.8), while in the case of soils, the predominant range was from 100 to 500 µm. The prevalent polymers in both, composts and soils, were PTFE, TPE, PP, and PET, with four times higher amounts in composts than in soils. Ingestion of common MPs were also verified in two earthworm species, which ingested concentrations higher than 2.1% w/w. PP was the most ingested MP and Eisenia fetida was more voracious compared with Lumbricus terrestris. Therefore, it can be considered a suitable bioindicator for monitoring microplastic contamination in agricultural soil.Graphical

Short-term microplastic effects on marine meiofauna abundance, diversity and community composition.

Due to the copious disposal of plastics, marine ecosystems receive a large part of this waste. Microplastics (MPs) are solid particles smaller than 5 millimeters in size. Among the plastic polymers, polystyrene (PS) is one of the most commonly used and discarded. Due to its density being greater than that of water, it accumulates in marine sediments, potentially affecting benthic communities. This study investigated the ingestion of MP and their effect on the meiofauna community of a sandy beach. Meiofauna are an important trophic link between the basal and higher trophic levels of sedimentary food webs and may therefore be substantially involved in trophic transfer of MP and their associated compounds. We incubated microcosms without addition of MP (controls) and treatments contaminated with PS MP (1-µm) in marine sediments at three nominal concentrations (103, 105, 107particles/mL), for nine days, and sampled for meiofauna with collections every three days. At each sampling time, meiofauna were collected, quantified and identified to higher-taxon level, and ingestion of MP was quantified under an epifluorescence microscope. Except for Tardigrada, all meiofauna taxa (Nematoda, turbellarians, Copepoda, Nauplii, Acari and Gastrotricha) ingested MP. Absorption was strongly dose dependent, being highest at 107 particles/mL, very low at 105 particles/mL and non-demonstrable at 103 particles/mL. Nematodes accumulated MP mainly in the intestine; MP abundance in the intestine increased with increasing incubation time. The total meiofauna density and species richness were significantly lower at the lowest MP concentration, while at the highest concentration these parameters were very similar to the control. In contrast, Shannon-Wiener diversity and evenness were greater in treatments with low MP concentration. However, these results should be interpreted with caution because of the low meiofauna abundances at the lower two MP concentrations. At the highest MP concentration, abundance, taxonomic diversity and community structure of a beach meiofauna community were not significantly affected, suggesting that MP effects on meiofauna are at most subtle. However, lower MP concentrations did cause substantial declines in abundance and diversity, in line with previous studies at the population and community level. While we can only speculate on the underlying mechanism(s) of this counterintuitive response, results suggest that further research is needed to better understand MP effects on marine benthic communities.

Rose or Red, but Still under Threat: Comparing Microplastics Ingestion between Two Sympatric Marine Crustacean Species (Aristaeomorpha foliacea and Parapenaeus longirostris).

Increasing plastic contamination poses a serious threat to marine organisms. Microplastics (MPs) ingestion can represent a risk for the organism itself and for the ultimate consumer. Through the analysis of the gastrointestinal tract, coupled with stable isotope analysis on the muscle tissue, this study provides insights into the relationship between MPs pollution and ecology in two commercial marine species caught in the Central Tyrrhenian Sea: Aristaeomorpha foliacea and Parapenaeus longirostris. Stable isotope analysis was conducted to determine the trophic position and the trophic niche width. The gastrointestinal tracts were processed, and the resultant MPs were analysed under FT-IR spectroscopy to estimate the occurrence, abundance, and typology of the ingested MPs. The trophic level of the species was similar (P. longirostris TP = 3 ± 0.10 and A. foliacea TP = 3.1 ± 0.08), with an important trophic niche overlap, where 38% and 52% of P. longirostris and A. foliacea has ingested MPs, respectively. Though species-level differences may not be evident regarding MP's abundance per individual, a high degree of dissimilarity was noted in the typologies of ingested particles. This research provides valuable insights into how MPs enter marine trophic webs, stressing that isotopic niche analysis should be combined with other methods to explain in detail the differences in MPs ingestion.

Effect of parasitic infection on microplastic ingestion in a native leuciscid hybrid species (Alburnus derjugini x Squalius orientalis) from Kürtün Dam Lake, Türkiye

Microplastic (MP) pollution is currently one of the most serious environmental issues. MPs were investigated in the Kürtün Dam Lake in healthy individuals of the native leuciscid hybrid (Alburnus derjugini x Squalius orientalis) species and individuals infected with the Ligula intestinalis parasite. Although MP abundance appeared to be higher in non-infected fish (NIF) than in L. intestinalis (L) and infected fish (IF), the MP abundance in IF was higher, because the parasite theoretically belongs to IF. In addition to the observation of MPs in the gastrointestinal tract (GIT) of fish, the diffusion of MPs by parasites settled in the body cavity indicates that MPs are not only present in the GIT. Therefore, predation on existing fish by birds causes MP dispersion. In the present study, the most common MP shape was fiber (100% for NIF and IF, 85.7% for L), the MP color was black (57.1% for IF and L) and orange (50% for NIF), and the polymer type was polyamide (57.1% for IF, 50% for NIF) and polyethylene terephthalate (28.5% for L). These MP compositions led us to believe that textile effluents and aquaculture operations in dam lakes could be sources of pollution. Therefore, this study provides insights for future research to elucidate the connection between MP consumption and parasite infection.

Microplastic characterization in the stomachs of swordfish (Xiphias gladius) from the western Mediterranean Sea

In this study, we aimed to quantify the presence of microplastics (MPs) in the stomachs of large pelagic fish (swordfish, Xiphias gladius, Linnaeus, 1758) sampled in the western Mediterranean Sea, and assess temporal trends (2011–2012 vs. 2017–2019) in MP ingestion. MPs were extracted from stomachs and characterized by μ-Fourier transform infrared spectroscopy. Results highlighted the ingestion of MP in 39 out of 49 stomachs analysed. Ingested MPs consisted mostly of small (<1 mm) fibers (88.6 %, mean ± standard deviation = 2.5 ± 6.1 particles per stomach), with a greater frequency of occurrence (FO) in the second period (FO = 90 %, 3.3 ± 8.0 particles per stomach). The predominant colours were purple, black and blue, and polyethylene terephthalate was the most frequently detected polymer. These results are crucial for the development of management actions aimed at the conservation of swordfish in the Mediterranean Sea and the prevention of health risks to humans.

First identification of microplastics in human uterine fibroids and myometrium

Microplastics (MPs) pollution has received widespread attention in recent years as the use of plastics continues to increase. However, currently no studies have reported the finding of MPs in human uterine fibroids (UFs) and myometrium tissues. In this study, UFs tissues (n = 48) and myometrium tissues (n = 40) from 48 patients and myometrium tissues (n = 8) from healthy population were collected. Following digestion of the samples by 10% KOH and 30% H2O2, MPs were analyzed qualitatively and quantitatively using Raman spectroscopy. The 16 UFs and myometrium tissue samples contained an average of 1.5 ± 1.17 MP particles per gram of tissue. Notably, the abundance of MPs in the UFs tissues (2.13 ± 1.17 particles per gram) was higher than in the myometrium tissues (0.88 ± 0.78 particles per gram). In the same cohort of individuals with UFs, the quantities of MPs detected in the affected UFs tissue (2.63 ± 1.77 particles per gram) exceeded those detected in healthy tissue (1.08 ± 0.93 particles per gram), particularly in elderly patients. A correlation was observed between elevated MP levels and frequent consumption of takeout meals and bottled water among patients, indicating that MP ingestion through food sources might have contributed to the increased abundance and variety of MPs within UFs. Furthermore, UFs increased in size with higher concentrations of MPs, which may have been related to elevated levels of MPs-induced hormones. This study provides new insights into the assessment of the relationship between exposure to MPs and human disease risk.

Screening of optimal cleaning methods to reduce microplastic residues on strawberry surfaces: Characterization of microplastics in strawberry wash water

Microplastics are widespread in facility strawberry greenhouses and can be deposited on the surface of strawberries through air currents. Investigating effective cleaning methods represents a viable strategy to reduce human ingestion of MPs. Therefore, different cleaning methods were compared: ultrasonic cleaning for 30 min, deionized water rinsing once, deionized water immersion for 30 min, and fruit immersion in washing salt for 30 min. The MPs in strawberry washing water were analyzed and compared using laser direct infrared imaging to investigate their characteristics and the optimal reduction of MPs on the surface of strawberries. The quality of the cleaning results was in the following order: water immersion > washing salt immersion > water rinsing > ultrasound. Water immersion was 1.3–2 times more effective in removing microplastics than other treatments. Furthermore, 21 polymer types were detected in the samples. Most MPs were less than 50 µm in size. The main polymers in this size range were polyamide, chlorinated polyethylene, and polyethylene terephthalate, and they mainly existed as fragments, fibers, and beads. This study provides a valuable reference for reducing human intake of microplastics through fresh fruits and vegetables.

Occurrence of microplastics in commercial fish species from the Ethiopian rift valley's Lake Hawassa, Ethiopia.

Microplastics (MPs) have recently been detected as emergent pollutants in the Ethiopian rift valley lakes located close to rapidly expanding towns. We provide the first study of MPs ingestion of commercial fish species from Lake Hawassa, Ethiopia: Catfish (Clarias gariepinus) and Nile Tilapia (Oreochromis niloticus). A total of 60 individual fish species was collected from three sampling sites of lake Hawassa in October 2020. Across all sampling sites, there was a significant difference in ingested MPs between benthic omnivore catfish and pelagic phytoplanktivorous Tilapia (χ2 = 15.864, p < 0.001). The most common size of ingested MPs (84.6%) was 0.5-1mm, with fragments (59.5%) dominating, followed by fibers (25.4%). On average, 4.03 ± 1.33 MPs with sizes ranging between 60μm and 10.53mm were detected per individual. White and yellow MPs were particularly numerous, accounting for 36.8% and 26.4% of the total, respectively. Because Lake Hawassa's fishery is so significant, the potential impact of MP pollution on the lake biota in general, and economically valuable fish species in particular, deserves attention, additional research, and, if possible, early mitigation.

First occurrence and risk assessment of microplastics in enteral nutrition formulas

Occurrence and characteristics of microplastics were evaluated in enteral nutrition formulas, for the first time. A total of 30 samples belonging to 9 brands were analysed. Physical and chemical characteristics of microplastics were identified by stereomicroscopy and micro-raman spectroscopy, respectively. The mean number of microplastics was 45 ± 63 MP/L. Two different shapes of microplastics were detected with fibres (62%) being the most common microplastics followed by fragments (38%). The most common color of microplastics was black (37%) followed by blue (26%), orange (15%), green (7%), red (7%), grey (4%) and multicolor (4%). The length of microplastics ranged from 10 to 2086 μm with an average of 548 ± 526 μm. Estimated mean daily microplastic intake for four different scenarios varied between 24 to 61 and 30 to 76 MPs/day for women and men, respectively. The mean polymer hazard index and microplastic load index levels were calculated as 380 and 1.30, respectively. The results of this study showed that microplastics are prevalent in enteral nutrition products. The presence of polymers with high hazard risk scores in enteral nutrition formulas may pose a risk to the health of patients with special nutritional needs.

Diet characteristics of tidal creek-associated fishes of the northeastern Arabian Sea with special reference to microplastic ingestion

The present study assessed the diet characteristics, trophic guild structure, and microplastics (MPs) ingestion by a group of fish sourced from the tidal creeks of the Mumbai coast along the Eastern Arabian Sea. The diet patterns were characterized using gastro-somatic index (GaSI), relative length of gut (RGL), diet overlap (α), diet breadth (Bi), and relative abundance of food items (%IOP), with a special emphasis on MPs contamination. The findings revealed that teleost and shrimps are the most preferred food items for these species. Whereas MPs contribute 5.50% of the total diet composition of the selected fishes. Additionally, we tried to find out the influence of fish size and dietary attributes on MP ingestion, identifying trophic level as a significant factor influencing contamination levels. Using the Polymer Hazard Index (PHI), the potential risks posed by MPs in fish samples were assessed, revealing notable discrepancies among polymers. For instance, polyvinyl chloride showed the highest PHI score of 198.75 and a hazard score reaching the highest risk category (IV), indicating substantial environmental risk. In summary, our findings highlight the impact of fish diet characteristics on MPs contamination and the varying levels of MP risks along the Mumbai coast, categorized according to polymer type from low to high risk.

Micro‐ and nano‐plastic loads in fish and macroinvertebrates in a tropical river

Abstract This study examines microplastic contamination in river macroinvertebrates and fish within a rapidly urbanising tropical catchment, and provides data on the quantity of microplastics ingested by various taxonomic and functional feeding groups. We employed both a widely used low‐resolution visual inspection method, capable of identifying microplastics ranging from 0.1 to 5 mm, and a novel automated method specifically designed to identify smaller plastics in the nano size range, from 0.004 to 0.1 mm. Analysis using the low‐resolution method indicated that a significant portion of fish (95%) and macroinvertebrates (44%) contained larger microplastics. The composition of microplastic within the animals differed from that in river water and on the river bed: microplastics in the water and on the bed were predominantly fibres (98% and 92% respectively), whereas the animals exhibited a more even mix of fibres (c. 35%), fragments (c. 43%), and film (c. 22%). Microplastic loads in aquatic organisms correlated with feeding group and body size, although patterns were not always consistent. Larger individuals generally contained more microplastic, especially among macroinvertebrates, but this trend was not observed uniformly among fish species. Additionally, differences in body loads among macroinvertebrate taxa and feeding groups varied depending on whether loads were expressed per individual or per unit weight. Use of the high‐resolution enumeration method revealed a substantially higher microplastic count compared to the low‐resolution method, highlighting the potential underestimation of contamination levels by the latter. The study underscores the non‐random uptake of microplastics by aquatic biota, influenced by feeding mode, and stresses the necessity of high‐resolution sample processing for accurate quantification of contamination levels and risk assessment for smaller organisms.

Microplastics Biofragmentation and Degradation Kinetics in the Plastivore Insect Tenebrio molitor.

The insect Tenebrio molitor possesses an exceptional capacity for ultrafast plastic biodegradation within 1 day of gut retention, but the kinetics remains unknown. Herein, we investigated the biofragmentation and degradation kinetics of different microplastics (MPs), i.e., polyethylene (PE), poly(vinyl chloride) (PVC), and poly(lactic acid) (PLA), in T. molitor larvae. The intestinal reactions contributing to the in vivo MPs biodegradation were concurrently examined by utilizing aggregated-induced emission (AIE) probes. Our findings revealed that the intestinal biofragmentation rates essentially followed the order of PLA > PE > PVC. Notably, all MPs displayed retention effects in the intestine, with PVC requiring the longest duration for complete removal/digestion. The dynamic rate constant of degradable MPs (0.2108 h-1 for PLA) was significantly higher than that of persistent MPs (0.0675 and 0.0501 h-1 for PE and PVC, respectively) during the digestive gut retention. Surprisingly,T. molitor larvae instinctively modulated their internal digestive environment in response to in vivo biodegradation of various MP polymers. Esterase activity and intestinal acidification both significantly increased following MPs ingestion. The highest esterase and acidification levels were observed in the PLA-fed and PVC-fed larvae, respectively. High digestive esterase activity and relatively low acidification levels inT. molitor larvae may, to some extent, contribute to more efficient MPs removal within the plastic-degrading insect. This work provided important understanding of MPs biofragmentation and intestinal responses to in vivo MPs biodegradation in plastic-degrading insects.

Tracing microplastic pollution in Mahi River estuary, Gulf of Khambhat, Gujarat, and their influence on functional traits of macrobenthos.

Most maritime habitats contain microplastic (MPs) contamination. The quality of the benthic ecosystem's habitat is declining as MPs accumulate in marine system. The contamination of MPs must therefore be investigated. We studied MPs pollution in the Mahi River, estuary, and macrobenthos. In the present study, the abundance of MPs fragments gradually decreased from the high tide zone to the low tide zone and muddy sediment has high MPsconcentrations due to sediment characteristics and particle size. The majority of sediment and biota MPs were fibrous and black. MPs in both silt and biota have identical chemical compositions (modified cellulose), shapes, and colors. A significant source of pollutants and MPs fluxing into the ocean is well within the river system. Perinereis aibuhitensis ingested the most MPs out of 11 species, whereas Amphipods did not show any presence of MPs. Our findings showed that functional characteristics are essential for macrobenthos MPs intake. MPs in macrobenthos are high due to biological functions such as feeding, ecological groups, feeding mechanisms, body size, and bioturbation. MPs in marine sediment and organisms aretracked down to the Mahi River exceeding 50km. The present work has investigated the idea that the macrobenthos that live in the sediment are ingesting the MPs that are building up there and this ingestion relies on the macrobenthos' functional characteristics.

Ecological assessment of microplastic contamination in surface water and commercially important edible fishes off Kadalundi estuary, Southwest coast of India.

This study focuses on the Kadalundi estuary, Kerala's first community reserve, investigating the prevalence and impacts of microplastics on both the estuarine environment and selected fish species. This study presents the initial evidence indicating the consumption of microplastic particles by 12 commercially important edible fish species inhabiting the Kadalundi estuary. Analysis revealed significant accumulations of microplastic fibers within the surface water. In examining 12 fish species from demersal and pelagic habitats, microplastics were found in both the gastrointestinal tracts and gills. In the digestive tracts, microplastic fragments constituted the highest proportion (46%), while in the gills, microplastic fibers were dominant (52.4%). This study observed a prevalence of blue microplastics over other colors in both water and fish samples. Notably, demersal species showed a higher incidence of ingested microplastics. Polymer analysis identified Polypropylene (PP), Nylon, Low-Density Polyethylene (LDPE), Polyethylene (PE), Polypropylene isotactic (iPP), PE 1 Octene copolymer, and Rayon in water samples, while fish samples predominantly contained LDPE, PP, PE, and Nylon. Risk assessment utilizing the Polymer Hazard Index (PHI) categorized certain polymers as posing minor to moderate risks. Pollution Load Index (PLI) computations indicated moderate to high levels of microplastic contamination across various sampling sites in the estuary. Principal Component Analysis (PCA) revealed a lack of correlation between fish size and microplastic ingestion, underscoring environmental factors' influence on microplastic intake. The study emphasizes the implications of microplastic pollution on the fragile ecosystem of the Kadalundi estuary, posing potential risks to biodiversity and human health.