Microplastic Retention Research Articles

Microplastics occurrence and fate in full-scale treatment wetlands

Treatment wetlands (TWs) are an efficient technology for removing microplastics (MPs) from wastewater, according to previous studies. This study investigates the dynamics and fate of MPs in two wastewater treatment plants (WWTPs) using TWs, one with horizontal subsurface flow (HF) and another with a floating plant system (FS). Special attention is paid to the retention produced in the sludge and the role of macrophyte roots. The abundance of MPs in the influent to the WWTPs was on average 20.3 ± 0.85 MP/L and 8.4 ± 1.13 MP/L in HF and FS respectively, while the effluent had 0.58 ± 0.07 MP/L and 0.17 ± 0.06 MP/L, thus giving overall efficiencies of 97.42% and 98.13%, respectively. In the HF wetland, sludge samples near the inlet and the outlet were taken, distinguishing between sludge adhered to gravel and sludge attached to roots. In the floating macrophytes, sludge samples from secondary and tertiary treatments were taken. The results indicate that roots play a significant role in MPs retention. In the HF wetland, the complex formed by roots and gravel attached more MPs than gravel alone in the final zone of the wetland. In the FS, roots retained a significant quantity of MPs, both in the secondary and tertiary treatments, thus giving rise to a sludge less concentrated in MPs. This study aims to improve the knowledge of MPs behavior and fate in full-scale TWs, providing valuable information to enhance retention efficiency.

The effects of large roughness elements on the in-stream transport and retention of polystyrene microplastics

The mechanisms controlling transport and retention of microplastics (MPs) in riverine systems are not understood well. We investigated the impact of large roughness elements (LREs) on in-stream transport and retention of the ubiquitous polystyrene-microplastics (PS-MPs). Scaled experiments were conducted with and without LREs under various shear Reynolds numbers (Re*) in an ecohydraulics flume. Our results, for the first time, demonstrated a clear dependence of the MPs’ velocity on Re* in LREs-dominated channel. Two distinct regimes and thresholds were identified: lower Re* (≤ 15,000) regime corresponding to higher velocities of MPs ({U}_{MPs}^{*}> 0.45), and higher Re* (> 15,000) to lower {U}_{MPs}^{*} (< 0.45). The presence and higher density of LREs increased Re*, decreased {U}_{MPs}^{*}, and enhanced the PS-MPs capture. The LREs-generated turbulence kinetic energy (TKE) was found to be a good predictor of PS-MPs transport and retention rates, indicating the effectiveness of LREs in retaining PS-MPs in streams and rivers.

The Role of Estuarine Wetlands (Saltmarshes) in Sediment Microplastics Retention

Concerns regarding plastic pollution, especially microplastics, have increased, as they can be present in different environmental compartments, including estuarine areas and saltmarshes. Although saltmarshes are highly vulnerable to different human activities and pressures, they have the ability to trap/retain contaminants in their vegetated sediments. However, there is still little information regarding the role of saltmarshes in microplastic retention. Thus, the present study aims to investigate the capability of an estuarine saltmarsh to trap microplastics by comparing microplastic concentrations in vegetated (saltmarsh) and non-vegetated sediments. Microplastic content from sediment (vegetated and non-vegetated) samples collected at different sampling sites in Lima River estuary was estimated using previously optimised extraction protocols, and the observed particles were then characterised accordingly to their size, colour, shape, and polymer (by FTIR). Water samples were also collected and analysed for their microplastics content to complement MPs characterisation within the estuarine area. Microplastics were detected in all sediment samples, with fibres being the most common type of microplastic found, followed by fragments/particles. Overall, vegetated sediments, especially those of saltmarsh species Juncus maritimus, presented a higher number of plastic items. These results indicated that microplastics tend to be trapped in vegetated sediments, supporting the fact that saltmarshes have a significant influence on the transport, distribution, and accumulation of MPs in estuarine areas.

Macroinvertebrate ecosystem engineering affects streambed retention of microplastics

Previous article No AccessMacroinvertebrate Ecosystem Engineering Affects Streambed Retention of MicroplasticsSamuel Frederick Fritz, Lindsey K. Albertson, John L. Hobgood, Elizabeth Mohr, Hayley Oakland, and Geoffrey C. PooleSamuel Frederick Fritz Search for more articles by this author , Lindsey K. Albertson Search for more articles by this author , John L. Hobgood Search for more articles by this author , Elizabeth Mohr Search for more articles by this author , Hayley Oakland Search for more articles by this author , and Geoffrey C. Poole Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by Freshwater Science Just Accepted Published on behalf of the Society for Freshwater Science Article DOIhttps://doi.org/10.1086/724584 Views: 39Total views on this site HistoryAccepted February 09, 2023 © 2023 Society for Freshwater Science. All Rights reserved.PDF download Crossref reports no articles citing this article.

Distribution and removal of microplastics in a horizontal sub-surface flow laboratory constructed wetland and their effects on the treatment efficiency

Constructed wetlands are commonly used to treat domestic wastewater, but the extent to which microplastics are retained in constructed wetlands and the impact this has on their efficiency are not known. In this context, we investigated retention of microplastics (microbeads and fibres) and their effects on the removal of carbonaceous (expressed as chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and dissolved organic carbon (DOC)), nitrogenous (N-NH4+, N-NO3-, and N-NO2-), and phosphorous (P-PO43-) matters in a horizontal sub-surface flow laboratory constructed wetland (LCW) under continuous flow. The LCW was in operation for 257 days, with the first 78 days without microplastics and microplastics added weekly during the next 179 days. The presence of microplastics had no significant effect on COD, BOD5, DOC, N-NH4+, and N-NO3- removal, while a statistically significant decrease in N-NO2- and an increase in P-PO43- concentrations in the effluent were observed after the addition of microplastics. Microplastics were efficiently retained in the LCW, and only 0.296% and 0.003% of the total microbeads and fibres, respectively, were detected in the effluent. Thus, it is evident that constructed wetlands are an effective barrier to the release of microplastics into the aquatic environment, but the high retention and thus continuous accumulation of microplastics may alter the nutrient cycling in constructed wetlands.

Microplastic surface retention and mobility on hiking trails

Hiking and trail running are a source of microplastic (MP) pollution on recreational trails in wilderness and conservation areas; however, the fate of MPs deposited on trails is poorly understood as MP mobility on such surfaces has not yet been examined. In this study, we simulated heavy rainfall (100 mm/h) on trail surfaces with existing MP pollution (in situ MPs) and spiked with 99 ± 2 rubber MPs (100–940 μm). Runoff was collected for 15 min and spiked and in situ MPs were quantified. Hydrological, erosional and microplastic responses were evaluated in relation to slope, bulk density, soil moisture and surface condition indicators, including amounts and types of surface cover and soil physical attributes. The MPs were largely immobile, with 85–100% of spiked MPs retained on trail surfaces. In situ MPs were detected in the trail runoff, with the majority being polyurethane, polypropylene and polyester. Microplastic movement was primarily influenced by hydrological effects, and analysis indicated the main explanatory variable was total runoff volume, followed by soil slaking. Trail sections with at least 15% herbaceous cover or a layer of loose alluvium had higher MP retention. Areas of resource accrual may be preferentially enriched, suggesting MPs from outdoor recreation may be concentrated on and adjacent to recreational trails. Microplastics deposited on trails may have long term implications for biodiversity and ecosystem functioning in wilderness and conservation areas, particularly around the trail corridor.

Microplastics in different water samples (seawater, freshwater, and wastewater): Removal efficiency of membrane treatment processes

The distribution and fate of microplastics in different water sources and their treatment plants (seawater, three municipal wastewaters, a pharmaceutical factory wastewater, and three drinking waters) in France were studied. Currently, research in this field is still under exploration since almost no relevant standards or policies have been introduced for the detection, the removal, or the discharge of microplastics. This study used an improved quantitative and qualitative analytical methodology for microplastic detection by μ-FTIR carried out with siMPle analytical software. By investigation, wastewater was determined to contain the most abundant microplastics in quantity (4,203–42,000 MP·L−1), then followed by surface water/groundwater (153–19,836 MP·L−1) and seawater (around 420 MP·L−1). Polyethylene was the dominant material in almost all water types followed by polypropylene, polystyrene, and polyethylene terephthalate. Almost all treatment technologies could remove microplastics whatever the feed water types and concentration of microplastics, though some treatment processes or transport pipes could cause additional contamination from microplastics. The four WWTPs, three DWTPs, and SWTP in France provided, respectively, 87.8–99.8%, 82.3–99.9%, 69.0–96.0% removal/retention of MPs in quantity, and provided 97.3–100%, 91.9–99.9%, 92.2–98.1% removal/retention of MPs in surface area. Moreover, ultrafiltration was confirmed to be an effective technology for microplastic retention and control of dimensions of microplastics in smaller ranges both in field-scale and lab-scale experiments. The 200 kDa ultrafiltration membrane could retain 70–100% and 80–100% of microplastics in quantity and in surface area, respectively.

Identification of microplastic pathways within a typical European urban wastewater system

AbstractIn recent years, thermoextraction/desorption‐gas chromatography/mass spectrometry (TED‐GC/MS) has been developed as a rapid detection method for the determination of microplastics (MP) mass contents in numerous environmentally relevant matrices and, in particular, for the measurement of polymers in water samples without time‐consuming sample preparation. The TED‐GC/MS method was applied to investigate a typical European municipal wastewater system for possible MP masses. Such investigations are important in view of the recent revision of the Urban Wastewater Treatment Directive. Four different representative sampling sites were selected: greywater (domestic wastewater without toilet), combined sewer, and influent and effluent of a wastewater treatment plant (WWTP). All samples were collected by fractional filtration. Filtration was carried out over mesh sizes of 500, 100, 50, and in some cases, 5 µm. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) were detected in all samples, with the PE fraction dominating in all cases. Styrene‐butadiene rubber which serves as an indication of tire abrasion, was only found in the influent of the WWTP. The highest MP mass contents were found in the combined sewer, so MP can become a source of pollution during heavy rain events when the capacity limits of the effluent are reached, and the polluted effluent is released uncontrolled into the environment. Based on the studies, MP retention from the WWTP could be estimated to be approximately 96%. Few trends in polymer type or mass contents were detected within the different fractions of the samples or when comparing samples to each other.

Challenges of using leaves as a biomonitoring system to assess airborne microplastic deposition on urban tree canopies

Monitoring microplastic concentrations in the atmosphere is critical for assessing their inhalation risk in urban areas and other ecological impacts on the natural environment. To assess these risks, leaves in tree canopies could be used as a biomonitoring system, but this requires knowledge of the potential variability of microplastic concentrations based on leaf properties and position in the tree. This study aims to quantify this potential variability by analyzing the concentration of airborne microplastics on leaves in Los Angeles as a function of leaf height, leaf surface hydrophobicity, and land use. Microplastic concentrations on leaves varied between 0.14 and 25 particles(n) cm−2, but the concentration peaked within 0.6–1.2 m height above ground, indicating the position of the leaf above the ground could matter. Microplastic concentrations varied significantly between leaf types indicating leaf surface properties could influence the retention of microplastics. Contact angle measurements revealed that the hydrophilicity of leaves had a weak correlation with microplastic concentrations on leaves, indicating other factors such as surface roughness or leaf features could be important for microplastic retention. Land-use type did not affect microplastic concentration. The results confirmed a high uncertainty in predicting microplastic concentration on leaves in the urban canopy, which limits their ability to be used as biomonitoring systems for microplastic pollution in urban areas.

New Perspective on the Mobilization of Microplastics through Capillary Fringe Fluctuation in a Tidal Aquifer Environment

The presence of plastic fragments in the environment is a growing global concern. In this study, we explored the effects of dynamic fluctuations of capillary fringe on the transport of microplastics (MPs) in the substrate combining various environmental and MP properties. Both experimental and Hydrus-2D modeling results confirmed that increasing cycles of water table fluctuation led to the rise of capillary fringe. An increase in the cycles of water table fluctuations did not significantly change the overall MP retention percentages in 0.5 mm substrate but altered the MP distribution along the column. In 1 and 2 mm substrate, the increase in cycle numbers enhanced the MP transport from substrate to the water below. In terms of the size of the MPs, more 20-25 μm polyethylene (PE2) were retained in the substrate compared to 4-6 μm polyethylene (PE1) under the same number of fluctuation cycles. High-density polytetrafluoroethylene (PTFE, 5-6 μm) exhibited higher retention percentages compared to PE1 particles. Ultraviolet aging for 60 days enhanced PE1 transport along the column, while 60 days of seawater aging did not affect PE1 transport greatly. For PTFE, ultraviolet and seawater aging enhanced its retention in the substrate. The retention percentages of both PE1 and PTFE in the column increased with the elevated ionic strength and the decrease of fluctuation velocity. This work highlights that capillary fringe fluctuation can serve as a pathway to relocate MPs to the tidal aquifer.

Leaf morphology affects microplastic entrapment efficiency in freshwater macrophytes

Context In contrast to marine environments, microplastic pollution in freshwater systems is understudied. Previous research suggests that freshwater macrophytes function as microplastic sinks, which, because they are at the base of food webs, has implications for higher trophic levels. Aim This study compares the ability of freshwater plants with different leaf morphologies to trap downwelling microplastics. Method Microplastics (800–1000 μm polyamide grains) were deposited onto three macrophyte species, namely, Cabomba caroliniana, Egeria densa, and Hygrophila polysperma. Microplastic mass retained was calculated as the percentage of microplastic mass captured by the plant and standardised microplastic retention was calculated as the absolute microplastic mass retained (g) divided by plant dry mass (g). Results The amount of trapped microplastics differed significantly among species, with the highest amount trapped by C. caroliniana (39.3%; 7.91 g g−1), followed by E. densa (28.8%; 5.30 g g−1) and H. polysperma (17.6%; 4.47 g g−1). Conclusion Significant differences in microplastic retention among species may be attributed to variation in leaf morphology. Implications These findings have potential applications in bioremediation and biomonitoring, where freshwater macrophytes could help with the tracking and mitigation of microplastics in the environment.

Effects of waves, burial depth and material density on microplastic retention in coastal sediments

Coastal sediments, recognized as a major sink for microplastics (MPs), are subject to frequent physical disturbances, such as wave disturbance and associated sediment dynamics. Yet it remains poorly understood how wave disturbance regulates MPs accumulation in such a dynamic environment. Here, we examined the effects of waves and their interactions with material density and burial depth on the retention of MPs in coastal sediments, through manipulative experiments in a mangrove habitat along the coast of South China. The results clearly revealed that stronger waves removed more buried MPs from the sediments. Moreover, storms can have disproportional effects on MPs retention by inducing large waves and strong sediment erosion. We also demonstrated that MPs retention generally increased linearly with growing material density and non-linearly with raised burial depth in the sediment. Overall, our findings highlight the importance of both external and internal factors in shaping MPs retention in coastal ecosystems like mangroves, which is essential to assess and predict MPs accumulation patterns as well as its impacts on ecosystem functioning of such blue carbon habitats.

Characteristics of Microplastic in Commercial Aquatic Organisms

This study aims to review the occurrence of microplastics in some commercial aquatic organisms. Microplastics are small plastic particles with a diameter of less than 5 mm. Effluent, stormwater, agricultural, and surface runoff introduce microplastic to freshwater basins. Hydrodynamics and hydrology encompass microplastics. River flow speed can cause turbulence and riverbed instability, increasing microplastic concentrations. Fish, shellfish, and crustaceans ingest microplastics in proportion to their quantity in freshwater and marine environments. Human activities cause variations in the form, color, and size of microplastics in the biota. Animals absorb microplastics through trophic transfer. Increased microplastic residence time before ingestion promotes trophic transmission. Lower food concentration and aggregation enhance microplastic retention in zooplankton guts, increasing transmission to higher-trophic-level species. Most studies show that microplastics in biota are discovered in fish and crustacean intestines and bivalve tissues. Microplastic buildup can disrupt live organisms' growth and reproduction, induce oxidative stress, obstruct the digestive system, and damage the intestine. Microplastics may harm people's health if they eat contaminated seafood that contains them, but more research is needed.

Microplastics in Kuwait’s Wastewater Streams

The wastewater stream is the most significant contributor of microplastics (MPs) to the environment. There are five wastewater treatment plants (WWTPs) in Kuwait. This baseline study provides an overview of MP removal in three major WWTPs in Kuwait that treat some 81.31% of the wastewater produced. The Sulabiya WWTP was the most efficient in MP removal, followed by the Kabd and Umm Al-Haiman WWTPs. The MP removal efficiency of plants in Kuwait is very high for Sulabiya WWTP and Kabd WWTP with an average of 2.5 MP L−1 in treated effluent comparable to the WWTPs in Australia, the United States, and Europe. The standard methodology of sample collection, preparation, and identification using microscopic examination and micro-Raman spectrometry was followed. Over 94.5 billion MPs enter the three WWTPs daily; 92.3 billion MPs are retained in sludge, while 2.2 billion are passed into the environment due to the use of treated effluent. The influent, effluent, and sludge MP inventories ranged between 119 and 230 MP L−1, 1 and 12 MP L−1, and 72 and 103 MP 10 g−1 respectively. The fiber was the dominant shape, and white, transparent, and black were prevalent colors. Currently, sludge is not used in Kuwait for any terrestrial or agricultural application; however, sludge is routinely used in many countries as a soil additive in agricultural farms. Using effluent water in irrigation leads to MP dissemination in the terrestrial environment. It is necessary to assess how far these MPs move in the soil profile and if they can contaminate the shallow aquifers. The observation of MP retention in sludge and effluent is empirical, and the use of these matrixes in agriculture is likely to raise an issue of food safety.

A pore-scale investigation of microplastics migration and deposition during unsaturated flow in porous media

Microplastics are ubiquitous in the natural environment and have the potential to endanger the natural environment, ecology and even human health. A series of microfluidic experiments by using soft lithography technology were carried out to investigate the effect of flow rate, particle volume fraction, particle size and pore/throat ratio on microplastics migration and deposition at the pore scale. We discovered a range of deposition patterns of the spherical microplastics from no particle deposition, to discontinuous particle layer, and to continuous particle layers in the retained liquid in the pores, depending on the particle size and volume fraction. Several metrics, including air saturation, probability of particle detainment, expansion ratio and thickness of residual liquid, were quantified to examine the role of various parameters on particle migration and retention of microplastics. At low flow rate (Q = 0.05 μL/min), microplastics migration and deposition were sensitive to changes in particle volume fraction, particle size and pore/throat ratio. In contrast, at high flow rates (Q > 5 μL/min), the migration and retention of particles were mainly controlled by strongly channelized air invasion pattern, while the particle volume fraction, particle size and pore/throat size ratio have only secondary influence. At intermediate range of flow rates, microplastics migration and deposition were dramatically impacted by flow rate, particle volume fraction, particle size and pore/throat ratio. This work improves the understanding of the mechanisms of particle migration and retention in porous media and can provide a reference for more accurate assessment of the exposure levels and times of microplastics in soil and groundwater systems.

Removal of Microplastic Pollution through Waste Water Treatment: A Review

The presence of plastic materials in a water stream is a serious environmental concern because of their poor degradability characteristics. The enormous rise in the production of plastics causes a significant amount of plastic waste on the land to enter water bodies. If the particle size is small at the micro level (less than 5 mm in diameter), it has significant potential for blocking the fine pores of filtration and membrane systems. Their encroachment also poses a threat to human health in the food chain. Wastewater treatment plants (WWTPs) play an important role in removing a significant amount of microplastics; otherwise, they end up in the process of bioaccumulation. This study provides an idea about the characteristics of microplastics, removal efficiency, and the correlation between wastewater quality and microplastic concentrations from three different WWTPs that differ in the biological and advanced wastewater treatment techniques, which are believed to play an important role in microplastic removal. It also focuses on how waste treatment facilities affect the retention of microplastics and discusses issues with using sewage sludge laden with microplastic.

Deciphering the role of polyethylene microplastics on antibiotic resistance genes and mobile genetic elements fate in sludge thermophilic anaerobic digestion process

The retention of microplastics in sewage sludge, a reservoir of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs), has attracted increasing attention. However, the impact of polyethylene microplastics (PE-MP) on the fate of ARGs and MGEs is far from fully understood in sewage sludge's thermophilic anaerobic digestion process (AD). The present study demonstrated that PE-MP with the size of 40–48 µm at concentrations of 50, 100, and 200 particles/g-TS could enlarge total ARGs abundance. Meanwhile, a significant positive (r = 0.96, p < 0.05) correlation was observed between PE-MP concentration and total MGEs content. Microbial analysis revealed the enrichment of some functional genus under the stress of PE-MP, which might be the potential host of ARGs and MGEs. The relative abundance of acetogens Thermoanaerobacter increased from 27.60 % to 32.80 % and hydrolytic bacteria Caldicoprobacter enriched by 28.03 % when PE-MP content increased from zero to 200 particles/g-TS. The potential hosts were subsequently identified through co-occurrence networks, some of which were identified as pathogens. Strong positive correlations between PE-MP, ARGs, and MGEs were observed using redundancy analysis and correlation analysis. Additionally, the structural equation model indicated the direct and indirect influence of PE-MP on the abundance of ARGs and MGEs. MGEs could enhance the acquisition and dissemination of ARGs directly. Taking together, our findings deciphered the contribution of PE-MP to the spread of ARGs and MGEs in the sludge AD process, which might pose risks to human health and should be considered during sewage sludge disposal.

Facilitated transport of microplastics and nonylphenol in porous media with variations in physicochemical heterogeneity

Nonylphenol (Noph) has garnered worldwide concern as a typical endocrine disruptor due to its toxicity, estrogenic properties, and widespread contamination. To better elucidate the interaction of Noph with ubiquitously existing microplastics (MPs) and the potential interdependence of their transport behaviors, batch adsorption and column experiments were conducted, paired with mathematical modeling. Compared with sand, MPs and soil colloids show stronger adsorption affinity for Noph due to the formation of hydrogen bonding and the larger numbers of interaction sites that are available on solid surfaces. Limited amount of soil-colloid coating on sand grains significantly influenced transport behaviors and the sensitivity to solution chemistry. These coatings led to a monotonic increase in Noph retention and a nonmonotonic MPs retention in single systems because of the altered physicochemical properties. The mobility of both MPs and Noph was enhanced when they coexisted, resulting from their association, increased electrostatic repulsion, and competition on retention sites. Limited release of MPs and Noph (under reduced ionic strength (IS) and increased pH) indicated strong interactions in irreversible retention. The retention and release of Noph were independent of IS and solution pH. A one-site model with a blocking term and a two-site kinetic model well described the transport of MPs and Noph, respectively. Our findings highlight the essential roles of coexisting MPs and Noph on their transport behaviors, depending on their concentrations, IS, and physicochemical properties of the porous media. The new knowledge from this study refreshes our understanding of the co-transport of MPs and organic contaminants such as Noph in the subsurface.

Distribution and retention of microplastics in plantation mangrove forest sediments

Microplastics (MPs) in ocean tides can be effectively intercepted by mangroves, especially sediments, which are considered to be effective sinks. However, the retention of plantation mangrove forests on MPs is still unclear. In this study, the spatial distribution and its implication factors of MPs in surface sediments of plantation mangrove forests were investigated for the first time. In plantation forests, MPs were detected with abundances ranging from 67 ± 21 to 203 ± 25 items/kg, and plantation forests were significantly lower than natural forests at the CJ sampling site (p < 0.05). Plantation forests had fewer fibrous MPs than natural forests (p < 0.05). Furthermore, the MPs abundance showed strong linear relationships with the sand content (p = 0.002, R2 = 0.86) and Aegiceras corniculata biomass (p = 0.001, R2 = 0.84). Partial least squares path modeling analysis (PLS-PM) indicated that these two factors influenced MPs abundance by retaining MPs with fibrous, fragmented, denser and larger-sized characteristics. Our results revealed the differences in MPs abundance and characteristics between plantation and natural mangrove forests, and it is necessary to monitor MPs pollution to provide significant guidance for the restoration of constructed wetlands.

Microplastics in seawater and marine organisms: Site-specific variations over two-year study in Giglio Island (North Tyrrhenian Sea)

Geographical and temporal differences of microplastic occurrence were documented in water and fish collected in 2017 and 2019 from the Giglio Island (North Tyrrhenian Sea) close to the area where the Costa Concordia sank in January 2012. Results on water samples showed a site-dependent difference, suggesting the role of surface current dynamics in the microplastic local distribution, while tested Neuston nets (200 μm and 330 μm mesh size) did not influence microplastic retention efficiency. Fish exhibited in 2019 a higher frequency of specimens positive to microplastic ingestion with respect to 2017, with an occurrence higher than those typically observed in other Mediterranean areas. Both in water and fish, fragments were the dominating shape, polypropylene and polyethylene were the prevalent polymers, without particular difference between sites and years. This study highlights the importance of applying microplastic investigation in biotic and abiotic matrices for an effective monitoring of this pollution in the marine environment.