Microplastic Abundance in Rainbow Trout Life Cycle: Step by Step

Fish and Fisheries, 2021

Microplastics (MPs) are small, plastic particles of various shapes, sizes and polymers. Although well studied in marine systems, their roles and importance in freshwater environments remain uncertain. Nevertheless, the restricted ranges and variable traits of freshwater fishes result in their communities being important receptors and strong bioindicators of MP pollution. Here, the current knowledge on MPs in freshwater fishes is synthesized, along with the development of recommendations for future research and sample processing. MPs are commonly ingested and passively taken up by numerous freshwater fishes, with ingestion patterns often related to individual traits (e.g. body size, trophic level) and environmental factors (e.g. local urbanization, habitat features). Controlled MP exposure studies highlight various effects on fish physiology, biochemistry and behaviour that are often complex, unpredictable, species-specific and nonlinear in respect of dose-response relationships. Egestion is typically rapid and effective, although particles of a particular shape and/ or size may remain, or translocate across the intestinal wall to other organs via the blood. Regarding future studies, there is a need to understand the interactions of MP pollution with other anthropogenic stressors (e.g. warming, eutrophication), with a concomitant requirement to increase the complexity of studies to enable impact assessment at population, community and ecosystem levels, and to determine whether there are consequences for processes, such as parasite transmission, where MPs could vector parasites or increase infection susceptibility. This knowledge will determine the extent to which MP pollution can be considered a major anthropogenic stressor of freshwaters in this era of global environmental change.

Limnology and Oceanography Letters, 2020

Microplastics in the environment can impact feeding and physiological functions of organisms. Most studies have focused on marine systems, and studies of lacustrine organisms are less common. We examined microplastic concentration in 72 gizzard shad and 24 largemouth bass from two agricultural reservoirs in the midwestern U.S.A. with differing shoreline development. Microplastics were found in 100% of the fish, with 1–49 No. Fish−1, independent of shoreline development. Bass had higher concentrations overall than shad. For bass, microplastics were more concentrated in the guts rather than gills, but the opposite was the case for shad, suggesting that feeding guild may influence where microplastics accumulate in fishes. The prevalence and concentrations reported here are greater than reported in marine systems and higher than reported in riverine studies. Our results underscore the ubiquitous distribution of microplastics and suggest that lake ecosystems in agricultural landscapes ma...

Microplastics in fisheries and aquaculture: status of knowledge on their occurrence and implications for aquatic organisms and food safety FAO This report looks into the issue of microplastics from the fisheries and aquaculture perspective. Based on existing scientific literature, a group of experts assessed the potential impact of microplastics and related contaminants on fish consumers' health and the ecological implications for aquatic organisms. A workshop was organized with invited experts (Rome, 5-8 December 2016) who complemented the published information and carried out a risk profiling of microplastics in aquaculture and fishery products. Despite the large amount of scientific data available, there are still significant knowledge gaps, in particular regarding impacts at fish population and community level, detailed data for a proper risk assessment and implications of nanoplastics presence in the marine environment. Nonetheless, measures should be taken at international, governmental and consumer levels to undertake cost-effective ecological and seafood safety risk assessments on micro-and nanoplastics and associated polymers, to reduce plastic use and encourage the use of alternative materials, recycling and the adoption of sustainable practices in using plastics and managing plastic pollution.

Journal of Marine Science and Engineering

Microplastics have been found to accumulate in freshwater, marine ecosystems, and biological organisms. The frequency of studies on microplastic contamination in organs has increased recently, although there have been relatively fewer investigations on fish eggs in Thailand. To extract microplastics from catfish samples for laboratory analysis (Osteogeneiosus militaris), we used 10% potassium hydroxide in the digestion process. A needle penetrated the fish eggs to investigate microplastic contamination. We examined microplastics under a stereomicroscope and used Fourier transform infrared spectroscopy to determine the type of polymer. We found microplastic contamination in organs, most commonly in the stomach (0.91 ± 0.13 items/g), followed by tissue (0.53 ± 0.09 items/g), and gills (0.30 ± 0.03 items/g) at the level of significance p < 0.01. We found a total of 349 fish eggs with 27 items of microplastic. The dominant microplastic we found in the stomach, tissue, and gills of th...

International Journal of Science and Research , 2024

Microplastics (MPs) have become a global concern due to their pervasive presence in the environment, originating largely from discarded plastic fragments. These particles, smaller than 5 mm, may come from various sources including cosmetics, clothing fibers, and tire particles, posing a significant threat to aquatic life and human health. This study focused on the potential presence and ingestion of MPs by Nile tilapia (Oreochromis niloticus) cultured in the Magat Dam Reservoir in Ramon, Isabela, Philippines. The research aimed to determine the presence, type, shape, and color of MPs in Nile tilapia, considering the ecological and health implications of microplastic pollution in aquatic ecosystems and food sources. Sampling was conducted in three distinct zones of the reservoir-upper, middle, and lower. MPs were extracted from their gastrointestinal tracts of the sample fishes using the Wet Peroxide Oxidation technique. The MPs were characterized in terms of type, shape, and color using established criteria. Statistical analysis, employing One-Way Analysis of Variance (ANOVA), was conducted to discern differences in MP distribution across sampling areas. Results indicate a significant prevalence of fiber in the guts of Nile tilapia, suggesting its potential as a significant pollutant in the reservoir. MPs exhibited various shapes including elongated, angular, cylindrical, and degraded, with elongated fibers dominating the gastrointestinal tracts. The color spectrum of MPs ranged from white to black, with transparent MPs being the most abundant. This study underscores the urgent need for mitigation strategies to address microplastic pollution in aquatic environments, emphasizing the importance of sustainable practices to preserve both marine ecosystems and human health. Additionally, it contributes to the fulfillment of Sustainable Development Goals 6 and 14, advocating for clean water, sanitation, and the protection of life below water.

Marine pollution bulletin, 2018

Microplastic ingestion has been reported for several marine species, but the level of contamination in transitional systems and associated biota is less known. The aim of this study was to assess the occurrence of microplastic ingestion in three commercial fish species: the sea bass (Dicentrarchus labrax), the seabream (Diplodus vulgaris) and the flounder (Platichthys flesus) from the Mondego estuary (Portugal). Microplastics were extracted from the gastrointestinal tract of 120 individuals by visual inspection and digestion solution. A total of 157 particles were extracted from 38% of total fish (96% fibers), with 1.67 ± 0.27 (SD) microplastics per fish. Significantly higher amount of ingested microplastics was recorded for D. vulgaris (73%). The dominant polymers identified by μ-FTIR were polyester, polypropylene and rayon (semi-synthetic fiber). It is reported for the first time the presence of this pollutant in fish populations from the Mondego estuary raising concerns on their ...

Pollution, 2025

Microplastics in water has now become a significant problem in many water bodies which in turn impacts the different organisms that live in these water bodies. The study focuses on the ingestion of microplastics by Labeo rohita, which is a widely distributed and economically important freshwater fish species. The study focused on the detection and quantification of microplastics in the stomach of Labeo rohita collected from different sites exposing different degrees of pollution. Samples were obtained from three distinct freshwater environments: The first one represents a heavily polluted pond while the other is a moderately polluted pristine reservoir, and the third one, a river. The captured fish were examined and dissected using the light microscopy and Fourier-transform infrared (FTIR) spectroscopy for detection and enumeration of microplastics. Results showed that fish collected from the highly polluted pond contained the highest levels of microplastic with fibers and fragments being the most abundant. The fish collected from the moderately polluted pristine reservoir contained less microplastic particles, and those found in the river contained negligible amounts of contamination. Subsequent characterization of the findings indicated that microplastics are present in different organs such as the stomach and the intestines, which could point to the existence of bioaccumulation and possible physiological impacts. This paper also established the presence of microplastic pollution in Labeo rohita and calls for specific pollution control measures since existing measures have insufficient effects in controlling environmental pollutants.

Plastic production is escalating tremendously throughout the globe and the reason behind this is its durability and multipurpose utility. But there is a severe scarcity of its management. Tonnes of plastics are dumped into water bodies across the world. These plastics breakdown because of different reasons and results in the plastic debris of size <5mm termed as microplastics (MPs) which are hazardous to aquatic life. They are a potential source of toxins as they offer a large surface area to various chemicals present in the water body when these MPs are ingested by fishes it causes serious health issues leading to mortality of the fishes. Therefore, we comprehensively reviewed the sources of MPs in freshwater systems and its various types and how they get accumulated inside the body of fishes. We found that fishes ingest these particles by mistaken for food or accumulated these particles by consuming from lower trophic organisms. Some of the commonly studied MPs are PE, PS, and PVC, examined from the body of fishes. MPs can cause various ecotoxicological effects on fishes like behavioural change, cytotoxicity, neurotoxicity effects, and liver stress etc. Our review study finds that there is a paucity of information on the accumulation of MPs by freshwater fishes and there are very few studies on its effects also there is a debate whether this accumulation is subjected to the bio-magnification process which ultimately affects human life.

Marine Pollution Bulletin, 2018

Among aquatic organisms, fish are particularly susceptible to ingesting microplastic particles due to their attractive coloration, buoyancy, and resemblance to food. However, in previous experimental setups, fish were usually exposed to unrealistically high concentrations of microplastics, or the microplastics were deliberately contaminated with persistent organic chemicals; also, in many experiments, the fish were exposed only during the larval stages. The present study investigated the effects of virgin microplastics in gilt-head seabream (Sparus aurata) after 45 days' exposure at 0.1 g kg-1 bodyweight day-1 to 6 common types of microplastics. The overall growth, biochemical analyses of the blood, histopathology, and the potential of the microplastics to accumulate in gastrointestinal organs or translocate to the liver and muscles were monitored and recorded. The results revealed that ingestion of virgin microplastics does not cause imminent harm to the adult gilt-head seabream during 45 days of exposure and an additional 30 days of depuration. The retention of virgin microplastics in the gastrointestinal tract was fairly low, indicating effective elimination of microplastics from the body of the fish and no significant accumulation after successive meals. Therefore, both the short-and the long-term retention potential of microplastics in the gastrointestinal tract of fish is close to zero. However, some large particles remained trapped in the liver, and 5.3 % of all the livers analyzed contained at least one microplastic particle. In conclusion, the dietary exposure of S. aurata to 6 common types of virgin microplastics did not induce stress, alter the growth rate, cause pathology, or cause the microplastics to accumulate in the gastrointestinal tract of the fish.

Limnology and Oceanography Letters, 2019

Commercial fisheries yield essential foods, sustain cultural practices, and provide widespread employment around the globe. Commercially harvested species face a myriad of anthropogenic threats including degraded habitats, changing climate, overharvest, and pollution. Microplastics are pollutants of increasing concern, which are pervasive in the environment and can harbor or adsorb pollutants from surrounding waters. Aquatic organisms, including commercial species, encounter and ingest microplastics, but there is a paucity of data about those caught and cultured in North America. Additional research is needed to determine prevalence, physiological effects, and population‐level implications of microplastics in commercial species from Canada, the United States, and Mexico. Investigations into possible human health effects of microplastic exposure from seafood are also greatly needed. This synthesis summarizes current knowledge, identifies data gaps, and provides future research direct...