Presence Of Microplastics Research Articles

Natural substrates and amphipods epibionts contaminated by microplastic

Amphipods inhabit microhabitats that protect them against predation, provide nutrition and an area for reproduction and development. However, the compounds of the ecosystem are impacted by the presence of microplastics (MPs), which are a threat to marine communities. Since the organisms interact with and ingest/filter the different quantities of MPs, and may make it available to the associated epibionts, three natural substrates (algae, sponges, and ascidians) were sampled to compare the number of MPs in them and in their associated amphipods. This study was conducted on rocky shores from Rio de Janeiro (Brazil), differently from other studies that have been focused on experimental tests. The samples were submitted to density separation to extract the microplastics and acid degradation to access MP in amphipods. Algae retained a greater concentration of MPs as a sink of particles, as well as its associated amphipods. Sponges and ascidians have different mechanisms to filter water, which influences the MPs accumulation in amphipods. Those associated with sponges and ascidians had fewer microplastic particles. This is the first study comparing the retention of MP in different natural substrates and their amphipod epibionts, which gives information about microplastic contamination in these microhabitats and their associated organisms.

Microplastic ingestion by an aquatic ciliate: Functional response, modulation, and reduced population growth.

Microplastic particles are ubiquitous in aquatic environments and are considered a major threat to the large range of heterotrophic organisms that involuntarily consume them. However, there is current uncertainty around the mechanisms underpinning microplastic uptake by aquatic consumers and the consequences for both the fate of the microplastics and the growth potential of consumer populations. We performed a feeding experiment, exposing a model freshwater ciliate, Tetrahymena pyriformis, to six different microplastic concentrations and measured microplastic uptake and population growth over the course of several generations. Microplastic uptake increased in a saturating fashion with concentration, consistent with a Type II functional response, with a maximum feeding rate of 22 microplastic particles individual-1h-1. Interestingly, microplastic uptake decreased through time and we observed that, after egestion, microplastic particles aggregated, rendering them too large for re-consumption. We built and tested a simulation model which matched rates of microplastic uptake when incorporating functional response parameters and assuming 50% immobilisation of microplastics after egestion. Nevertheless, ciliate population growth was compromised by the presence of microplastics, decreasing by 43% over the full microplastic concentration range. Taken together, our results demonstrate the potential for aquatic ciliates to play an important role in the uptake, transfer, and modification of microplastics in freshwater environments with associated negative impacts on population fitness.

Microplastic in Australian processed organics: Abundance, characteristics and potential transport to soil ecosystem.

The extensive use and application of recycled organics, including biosolids and compost, has been considered as an effective waste management approach to reduce waste to landfills. However, concerns have been raised about the presence of microplastics (MPs) in these recycled organics and their subsequent transfer to soils. Although the presence of MPs in biosolids has been widely documented, our knowledge about the occurrence and characteristics of MPs in processed organic waste such as compost is still limited. The present study aimed to investigate the abundance, characteristics and potential sources of MPs (>25μm) in processed organic waste samples collected across eleven sites with different processing systems in Australia. This includes compost, digestate from anaerobic digestion and rapidly dehydrated food waste. MPs, mainly polyethylene, polypropylene and polyester, were found across all samples with concentrations ranging from 1500 to 16,000MP/kg dry weight. The majority of these MPs fell within the smaller size range of 25-500μm. Using the concentration and characteristics (size range, morphology, density) of detected MPs, the mass abundance of MPs was estimated to be between 7 and 760mg/kg dry weight. We also estimated that between 5.2×1010 to 6.2×1012MP/year could be transferred to the land via application of processed organic waste in Australia. The findings of this study also showed compostable bags as a potential source of MPs in some samples. This study provides the first evidence of MPs in processed organic waste in Australia and emphasises the need to more comprehensively understand the fate of MPs during the composting processes, their contribution to soil MP contamination, and their impacts on soil biota.

Limited effects of microplastics on size-fractionated phytoplankton booming in estuarine system.

Despite the extensive presence and long-term exposure risks of marine microplastics (MPs), their impact on phytoplankton at the community level is still not very clear, especially considering the various size classes of phytoplankton. To address this issue, we investigated the spatial load of MPs in Linhong Estuary and conducted in-situ experiments of algal culture with added MPs. Our investigation showed that the abundance of MPs varied from 8 n/L to 50 n/L, with an average of 21.76±12.31 n/L. A high loading of MPs was spatially identified outside Linhong Estuary, and clear decreasing trend from land to sea was not observed. Further microscopic examination revealed fiber-shaped MPs dominated in all collections, reaching a proportion of 93%. The chlorophyll a concentrations were 2.69-25.50μg/L (9.14±6.59μg/L), 0.68-3.13μg/L (1.48±0.67μg/L) and 0.14-0.65μg/L (0.27±0.14μg/L) for microphytoplankton (20-200μm), nanophytoplankton (2-20μm) and picophytoplankton (0.2-2μm), respectively. The correlation analysis between MP abundance and chlorophyll a of phytoplankton and the in-situ experiment at an environmentally realistic level both indicated a negative relationship between MP abundance and microphytoplankton with respect to chlorophyll a content, but no adverse effects of MPs were found for nanophytoplankton and picophytoplankton with smaller sizes. Our findings indicate that exposure to realistic levels of MPs only cause a limited impact on size-specific phytoplankton communities studied, but long-term interactions between MPs and these species merit further field-based assessment in real-world scenarios beyond lab-based incubation.

Microplastic pollution in salt marsh and urban tributary sediment cores of the River Thames estuary, UK: Spatial and temporal accumulation trends

Microplastics in sediment cores from urban tidal tributaries, Barking and Bow Creek-London and salt marshes Swanscombe, Kent, and Rainham, Essex, Thames estuary (UK), were quantified by density separation and ATR-FTIR spectroscopy. All eight tributary cores were dominated by low-density microplastics, polypropylene, polyethylene, and polystyrene with the greatest abundance (mean 360.0 ± 12.0 particles 100 g−1 dwt (0–10 cm depth) observed furthest from the confluence with the Thames due to storm tank combined-sewer-overflow input. Salt marsh core microplastics were highest at Swanscombe (mean 267.1 ± 10.2 particles 100 g−1 dwt at 0–10 cm depth) in the high-marsh vegetation zone. Marsh sediment radionuclide dating (Pb210, Cs137) suggested a presence of microplastics in the sediment since at least the late 1950s, with increasing abundance towards surface sediments. Tidal tributaries and salt marshes of the Thames act as natural filters, with salt marshes accumulating microplastics over time and tributaries acting as both stores and sources depending on individual site conditions and hydrodynamic variability.

The influence of road vehicle tyre wear on microplastics in a high-traffic university for sustainable transportation.

Road-associated microplastics, originating from tire wear and fragmented litter, are significant contributors to microplastic pollution. This study examines the characteristics of these particles within a university, focusing on their size, shape, color, and polymer composition. Suspended microplastics were collected using portable active samplers for PM10 and results have shown that PM10 concentrations peaked on Thursdays and declined, reaching their lowest levels on Sundays, with overall weekend measurements indicating reduced concentrations compared to weekdays. Importantly, the presence of microplastics correlated with increased PM10 levels. These findings highlighted a dominance of irregularly fragmented black microplastics, primarily composed of polyethylene, polypropylene, and polybutadiene, influenced mainly by vehicular movement. Additionally, metal contaminants such as aluminum, iron, and zinc were identified through SEM-EDX analysis of selected microplastics, particularly concentrated at the university's main entrance, the area with the highest traffic. This research enhances understanding of atmospheric microplastic pollution in university environments with heavy vehicle traffic and supports efforts to promote sustainable transportation and climate-friendly initiatives.

Study on Rapid Quantitative Detection of Soil MPs Based on Terahertz Time-Domain Spectroscopy.

The presence of microplastics (MPs) in agricultural soils substantially affects the growth, reproduction, feeding, survival, and immunity levels of soil biota. Therefore, it is crucial to investigate fast, effective, and accurate techniques for the detection of soil MPs. This work explores the integration of terahertz time-domain spectroscopy (THz-TDS) techniques with machine learning algorithms to develop a method for the classification and detection of MPs. First, THz spectral image data were preprocessed using moving average (MA). Subsequently, three classification models were developed, including random forest (RF), linear discriminant analysis, and support vector machine (SVM). Notably, the SVM model had an F1 score of 0.9817, demonstrating its ability to rapidly classify MPs in soil samples. Three regression models, namely, principal component regression (PCR), RF, and least squares support vector machine (LSSVM), were developed for the detection of three MPs polymers in agricultural soils. Six feature extraction methods were used to extract the relevant parts of the data containing key information. The results of the study showed that the regression accuracies of PCR, RF, and LSSVM were greater than 83%. Among them, the RF had the highest overall regression accuracy. Notably, PE-UVE-RF had the best performance with Rc2, Rp2, root mean square error of calibration, and root mean square error of prediction values of 0.9974, 0.9916, 0.1595, and 0.2680, respectively. Furthermore, this model gets a better performance by hypothesis testing and predicting real samples.

Microplastic pollution in aquatic ecosystems: impacts on diatom communities.

In recent years, heightened concern has emerged regarding the pervasive presence of microplastics in the environment, particularly in aquatic ecosystems. This concern has prompted extensive scientific inquiry into microplastics' ecological and physiological implications, including threats to biodiversity. The robust adsorption capacity of microplastic surfaces facilitates their widespread distribution throughout aquatic ecosystems, acting also as carriers of organic pollutants. However, to comprehensively understand the broader implications of this pollution, a thorough examination of the origins, composition, and widespread distribution of microplastics within aquatic biotopes is imperative. Diatoms, unicellular photosynthetic organisms, play a pivotal role in aquatic ecosystems as primary producers, forming the base of the aquatic food web. Investigating the relationship between microplastics and diatoms, leveraging methodological advancements, holds promise in unraveling the intricate action mechanisms underlying their interactions. Such inquiry sheds light on the physiological responses elicited and provides crucial insights into the ecological dynamics within aquatic environments. This study explores the understanding of microplastic-diatom interactions, focusing on how microplastic types, sizes, and concentrations influence diatoms. Ultimately, the current study strongly advocates for transdisciplinary collaborations, such as partnerships between ecologists, materials scientists, and policymakers, as the complexity of microplastic pollution demands collective efforts to address this critical and alarming environmental issue.

Analysis of the presence of microplastics in different brands of bottled water in Regional 6 - Ecuador

Attributable to the immoderate insertion of plastics into the food chain humans, this investigation was conducted with the aim of assessing the presence of microplastics in bottled water in Regional 6 of Ecuador. Accordingly, 72 samples from four different brands of bottled water were analyzed, revealing various plastic particles (fibers and fragments) which were subsequently confirmed through FTIR (Fourier Transform Infrared) Spectroscopy. Furthermore, a complete range of fragment sizes ranging from 4,4 µm to 248,29 µm and a complete range of fiber sizes from 102,64 µm to 840,20 µm were acquired., recognizing them as secondary microplastics. Nevertheless, upon comparing means regarding the fibers and fragments discovered in each brand, it was established that brand B had a greater quantity of microplastics, with an average of 233,1. Finally, polyethylene was identified as the most probable type of particle detected by FTIR.

Microplastic presence in dried and fresh fish from seafood markets in Sri Lanka

Context Microplastics have been found in aquatic ecosystems globally, including in many marine organisms. Despite this, understanding the occurrence of microplastics in seafood products prepared for human consumption has received less attention. Aims This study aims to determine the abundance and type of microplastic in dried and fresh fish purchased from seafood markets. Methods Four locally harvested species of anchovies and sardines were sampled from seafood markets across Sri Lanka. These pelagic species are popular seafood items and are commonly consumed whole. We analysed fresh (gastrointestinal tracts and whole body) and dried fish (whole body) under the microscope for microplastic presence (>38 μm, <5 mm), followed by polymer validation. Key results Across all fish sampled (N = 215), 82.3% had microplastic (3.64 ± 0.26 microplastics per individual), with fibre-shaped pieces making up more than 95% of all microplastic particles. Overall, contamination was higher in fresh fish than in whole dried fish. And, acrylic resin was the most common polymer. Conclusions Microplastics were found in nearly all fresh fish and almost half the dry fish from Sri Lanka, confirming the pervasive nature of microplastic contamination. Implications Differences in contamination levels in popular seafood products demonstrate how preparation and consumption habits can influence microplastic intake.

Biochar-microplastics interaction modulates soil nitrous oxide emissions and microbial communities

Biochar has been proposed as a soil amendment in vegetable fields, where the widespread use of plastic film leads to significant retention of microplastics (MPs) in the soil. However, the interactive effect of biochar and MPs on plant growth and soil functions remains poorly understood. Here, we conducted a pot experiment to examine the effects of biochar application in the presence of conventional and biodegradable microplastics (0.05% w/w) on the growth of coriander, soil nitrogen (N) cycling processes, and microbial communities. The results showed that biochar application increased aboveground biomass by increasing plant available N of NH4+, regardless of the presence of MPs. Biochar also significantly reduced soil nitrous oxide (N2O) emissions by an average of 16% without MPs. However, when MPs were present, the effect of biochar on N2O emissions was lessened depending on the MP type. Polylactic acid consistently reduced soil N2O emissions and the abundance of N2O production genes, irrespective of biochar application. Conversely, polyethylene without biochar reduced N2O emissions primarily by inhibiting N-related functional genes responsible for nitrification and denitrification. This inhibitory effect was reversed when biochar was applied, leading to a 26% increase in N2O emissions due to increased nifH and nirK gene abundance. Although biochar and MPs did not significantly alter microbial α-diversity, they altered the composition and structure of bacterial and fungal communities, linked to changes in soil N turnover. Our study underscores the critical role of MP type in assessing the effects of biochar on soil N cycling and N2O emissions. Consequently, plastic pollution may complicate the ability of biochar to improve plant growth and soil functions, depending on the characteristics of the MPs.Graphical

Identification of Characteristics, Abundance, Color, and Size of Microplastics in Shellfish in the Coastal Waters of Galesong Beach

The increasing presence of microplastics in the waters has been known to have the potential to enter various types of marine biota including shellfish. the type of research conducted was descriptive observational research) The research location was the coastal area of North Galesong Beach, Takalar Regency. The results showed that the average abundance of microplastics in mussels in Galesong Waters was 4,258 items/individual. The average (mean) intake rate of respondents was 185.86 gr/day, the median value was 167 gr/day. The minimum intake rate was 115 gr/day and the maximum intake rate was 300 gr/day. The mean exposure frequency of respondents was 126 days, the median was 104 days. The minimum exposure frequency was 54 days and the maximum exposure frequency was 255 gr/day. the types of microplastics found were all in the form of lines, fragments with red, blue and black colors. The size found was between 0.505-10.488 mm. The most common type of microplastics found in both sediments and mussels is the fragment form, followed by lines with a variety of colors, namely red, blue and black, there are differences in microplastics abundance between the two types of mussels, but differences in abundance can be seen between research stations as mussel habitat.

Presence of Microplastics and Additives Detected in Digestive Systems of Freshwater and Saltwater Fish Consumed by Humans in Puebla, Mexico

Presence of Microplastics and Additives Detected in Digestive Systems of Freshwater and Saltwater Fish Consumed by Humans in Puebla, Mexico

The combined effect of temperature and microplastics on Daphnia pulex Leydig, 1860 (Cladocera)

Microplastic contamination of freshwaters is on the rise due to anthropogenic activities. As a result, adverse effects on aquatic organisms, including cladocerans, have been observed. Cladocerans are widely used and recommended as bioassay organisms in ecotoxicological tests or as bioindicators of water pollution. Their generalist feeding habits make them capable of consuming microplastics. Here we exposed Daphnia pulex to two stressors, 30 µm microplastic beads and temperature (20 and 25 °C) and observed effects in terms of acute and sub-acute tests (LC50, filtration rates, and cardiac rhythm) and chronic tests (population growth and life table) for two generations. We hypothesized that the stressors would have a more pronounced negative effect in the F1 compared to the F0 generation. The adverse effects of microplastics were more evident in the acute toxicity tests than chronic toxicity tests and at 25 °C rather than 20 °C. Adult cladocerans consumed (in 20 min.) between 50 and 200 beads ind.-1, juveniles between 20 and 150 beads ind.-1, and neonates between 0 and 75 beads ind.-1. There was more than a 50% decrease in the ingestion rate and cardiac rhythm of the cladocerans in the presence of microplastics. Population growth rates were higher in the presence of microplastics due to greater and earlier investment in offspring production. We did not observe adverse effects of the 30 µm plastic beads on the survivorship-related variables of D. pulex. Further studies are needed to test the impact of this stressor over several generations to determine the effects of microplastics in food webs in contaminated aquatic ecosystems.

Quantifying microplastics concentration of invertebrates from three Antarctic fjords.

Microplastics, small pieces of plastic measuring less than five millimeters, have spread to all ecosystems, even those in the Southern Ocean around Antarctica. In particular, microplastics have been found contaminating water in emerging fjords, or inlets created by deglaciation, along the Antarctic Peninsula. Microplastics contamination puts fjord communities, which are unique and dominated by benthic species, at high risk for microplastic exposure leading to issues with feeding, endocrine disruption, and exposure to adsorbed toxins, all of which lower fecundity and survivability. The objective of this study was to quantify microplastics in invertebrates grouped according to feeding type. Invertebrates were collected from the Western Antarctic Peninsula fjords during 2017 and 2020 from three fjords via a mini-Agassiz trawl to quantify microplastic concentrations and identify polymer composition using Micro-ATR-FTIR. In 2017, 2.39 microplastics individual-1 were identified, while 5.01 microplastics individual-1 were identified in 2020. Out of the 24 polymers and polymer associates identified, the most common polymers were polypropylene, polycarbonate, polyamide, and polystyrene. Overall, the most common microplastic color category was black/brown/gblay, and fragments were the most common shape identified. Microplastics presence was significantly higher in the invertebrate organisms compared to procedural blanks (p<0.001), but feeding mechanism was not found to be a predictor of microplastic bioaccumulation. Microplastics concentrations in invertebrates differed between fjords in 2017 (p=0.010) but not in 2020. Complementing previous research on microplastics in Southern Ocean fjordic water, this study reveals new evidence of microplastics in Antarctic fjordic inhabitants.

Factors affecting microplastic pollution of sandboxes in urban residential areas: Simple methodology for quality control in the context of potential exposure assessment for children.

Occurrence of microplastics in the environment is well studied, but our knowledge of their distribution in specific locations, such as the sandboxes, which are integral parts of popular playgrounds for children, is limited. Pioneering research on the factors affecting the microplastic pollution of sandboxes in urban residential areas was conducted within three estates in Kielce, Poland. Sand samples (Σ27) were collected from nine sandboxes and examined for the presence of microplastics, using a simple quality control methodology proposed by the authors. Microplastics were found in each sample and their contents ranged from 60 to 5,540 items/kg of sand. Fragments and fibers were the most prevalent types of microplastics in the samples. They contributed to approximately 95% of all microplastics found. Transparent fibers were the most abundant among fibers (63%) and red particles (57%) among fragments. A strong, positive, and significant correlation (rSpearman = 0.90) was found between the number of microplastic items and the location of sandboxes (above sea level). There was no correlation between the population density of the estates (rSpearman = 0.03), the distance of the estates from the center (rSpearman = 0.02), and the distance of the estates from main roads (rSpearman = 0.43). Considering that sandboxes can be a potential source of microplastics for children, and assuming that sand ingestion by children is similar to the estimated daily soil ingestion rate, our results indicate that the number of microplastics ingested could be 1,106. Inhalation, dermal transport, and ingestion of microplastic particles from sandboxes pose a potential threat to children's health. However, more research is needed to better understand the health risks associated with this source of microplastics.

Rhamnolipid: nature-based solution for the removal of microplastics from the aquatic environment

Abstract Over the past two decades, research into the accumulation of small plastic particles and fibers in organisms and environmental settings has yielded over 7,000 studies, highlighting the widespread presence of microplastics in ecosystems, wildlife, and human bodies. In recent years, these contaminants have posed a significant threat to human, animal, and environmental health, with most efforts concentrated on removing them from aquatic systems. Given this urgency, the purpose of this study was to investigate the potential of rhamnolipid, a biosurfactant, for the removal of microplastics from water. Specifically, this study evaluates the effects of water matrix, initial pH of the solution (7.0, 7.5, 8.0, 8.5, 9.0, 9.5, and 10.0), concentrations of alum (5, 10, 20, 30, 40, and 50 mg/L), and concentrations of rhamnolipid (1, 5, 10, 20, 40, 80, and 100 mg/L). Optimum removal was achieved at alum and rhamnolipid concentrations of 5.0 mg/L and 1.0 mg/L, respectively, with a solution pH of 8.0. In both types of water tested, a removal efficiency of about 74% was determined, indicating the potential of rhamnolipid as a nature-based solution to control microplastic pollution in surface waters.

Examining the hidden dangers: Understanding how microplastics affect pregnancy.

Microplastics, a fast-growing environmental concern, play a crucial role in developing the major pollution crisis that affects nearly the entire surface of the planet. Microplastics are tiny particles, measuring less than 5mm which are ubiquitous, in occurrence, and found in a wide array of products including plastic packaging, synthetic textiles, seafood, fruits, vegetables, salt, sugar, bottled water, and even personal care products. The presence of microplastics in our environment and the potential adverse health effects they may cause have made them a significant perturbation in recent years. Pregnancy is a potentially life-changing experience that entails several apprehensions and new responsibilities for women. For expectant mothers, it is imperative to be aware of the implications of microplastics during pregnancy. One threatened concern is the potential transfer of microplastics across the placenta, which could expose the developing fetus to these particles. Although research on the impact of microplastics on pregnancy is still in its early stages, preliminary findings indicate potential risks that expectant mothers should be aware of. The timing of exposure during pregnancy may play a significant role in the potential risks associated with these tiny particles. In this review, we will delve into the topic, exploring how microplastics enter the body and the potential mechanism by which they pose risks to pregnancy outcomes.

Aged polylactic acid microplastics with ultraviolet irradiation stunted pakchoi (Brassica chinensis L.) germination and growth with cadmium in hydroponics.

The presence of biodegradable microplastics (BMPs) alongside toxic metals in soil significantly threatens plant health. Current research mainly focuses on the effects of original BMPs. In contrast, the specific impacts of ultraviolet (UV)-aged BMPs and their interaction with Cadmium (Cd) on seed germination and growth are unclear. Therefore, this study incubated aged polylactic acid (PLA) MPs through a UV irradiation aging process and used an indoor hydroponic experiment to systematically investigate the single and combined effects of Cd and BMPs (virgin and aged) on pakchoi (Brassica chinensis L.) germination, photosynthesis, antioxidant systems, and Cd accumulation. The results showed that after 21 days of UV irradiation (UPLA MPs), PLA MPs formed a fractured surface, demonstrating more detrimental effects on pakchoi than virgin ones. UPLA MPs and Cd alone inhibited pakchoi germination, growth, and photosynthesis, while PLA MPs alone promoted these processes. Combined treatment with Cd and UPLA MPs significantly increased oxidative damage and reduced pakchoi root length, chlorophyll, Mg, Mn, and Zn content. Under the combination of Cd and BMPs, PLA MPs could effectively alleviate the toxic effect of Cd on pakchoi. The results unraveled here emphasized that UPLA MPs, especially aged BMPs, could trigger adverse effects on agro-systems with heavy metals. Therefore, the results of this study can provide a new perspective and reference for the ecological risk evaluation of Cd and BMPs pollution in agricultural soils.

Association between microplastics in human amniotic fluid and pregnancy outcomes: Detection and characterization using Raman spectroscopy and pyrolysis GC/MS.

Microplastic contamination has emerged as a global environmental concern, while the limitation of single-technique identification methods in complex biological matrices calls for multi-analytical approaches for accurate microplastic detection. This study pioneers a dual-method approach, combining Raman spectroscopy and pyrolysis gas chromatography-mass spectrometry (Py-GC/MS), to investigate microplastics in human amniotic fluid. In total, samples from 48 pregnant women were collected and analyzed under stringent quality control measures, then Raman spectroscopy and Py-GC/MS were employed for comprehensive polymer identification and verification. Our analysis revealed 6 distinct microplastic polymer types in 39 subjects, with an average particle size of 3.05±1.05µm, polytetrafluoroethylene (PTFE, 31.25%), polystyrene (PS, 20.83%), and acrylonitrile-butadiene-styrene (ABS, 14.58%) being the most prevalent. Py-GC/MS analysis corroborated the Raman spectroscopy findings, identifying pyrolytic markers such as fluoroethylene for PTFE and styrene for PS. However, no significant associations were found between microplastic exposure and immediate adverse pregnancy outcomes. This study, for the first time, utilizes a dual-method approach combining Raman spectroscopy and Py-GC/MS to conclusively demonstrate the presence of diverse microplastics in human amniotic fluid, which underscores the need for larger-scale, longitudinal investigations to elucidate the potential long-term health implications of microplastic exposure.