Potential Source Of Microplastics Research Articles

Microplastic Contamination of Non-Mulched Agricultural Soils in Bangladesh: Detection, Characterization, Source Apportionment and Probabilistic Health Risk Assessment.

Microplastic contamination in agricultural soil is an emerging problem worldwide as it contaminates the food chain. Therefore, this research investigated the distribution of microplastics (MPs) in agricultural soils without mulch at various depths (0-5, 5-10, and 10-15 cm) across different zones: rural, local market, industrial, coastal, and research areas. The detection of MP types and morphology was conducted using FTIR and fluorescence microscopy, respectively. Eight types of MPs were identified, including high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polyvinyl fluoride (PVF), polyvinyl alcohol (PVA), and polytetrafluoroethylene (PTFE), with concentrations ranging from 0.6 ± 0.21 to 3.71 ± 2.36 MPs/g of soil. The study found no significant trends in MP concentration, with ranges of 0-2.1 ± 0.38, 0-2.87 ± 0.55, and 0-2.0 ± 0.34 MPs/g of soil at depths of 0-5 cm, 5-10 cm, and 10-15 cm, respectively. The highest MP quantity was recorded at 8.67 in coastal area, while the lowest was 6.44 in the local market area. Various MP shapes, e.g., fiber, film, pellet, fragment, and irregular, were observed across all layers. PCA suggested irrigation and organic manure as potential sources of MPs. The estimated concentrations of MPs possessed low non-carcinogenic and carcinogenic risks to the farming community of Bangladesh.

Toy building bricks as a potential source of microplastics and nanoplastics

Microplastics and nanoplastics have become noteworthy contaminants, affecting not only outdoor ecosystems but also making a notable impact within indoor environments. The release of microplastics and nanoplastics from commonly used plastic items remains a concern, and the characterisation of these contaminants is still challenging. This study focused on evaluating the microplastics and nanoplastics produced from plastic building bricks. Using Raman spectroscopy and correlation analysis, the plastic material used to manufacture building blocks was determined to be either acrylonitrile butadiene styrene (correlation value of 0.77) or polycarbonate (correlation value of 0.96). A principal component analysis (PCA) algorithm was optimised for improved detection of the debris particles released. Some challenges in microplastic analysis, such as the interference from the colourants in the building block materials, was explored and discussed. Combining Raman results with scanning electron microscopy - energy-dispersive X-ray spectroscopy, we found the scratches on the building blocks to be a significant source of contamination, estimated several thousand microplastics and several hundred thousand nanoplastics were generated per mm2 following simulated play activities. The potential exposure to microplastics and nanoplastics during play poses risks associated with the ingestion and inhalation of these minute plastic particles.

Are native microalgae consortia able to remove microplastics from wastewater effluents?

Wastewater Treatment Plants (WWTPs) are potential sources of microplastics (MPs) in the aquatic environment. This study aimed to investigate the potential of wastewater-native microalgae consortia to remove MPs from the effluent of two different types of WWTPs as a dual-purpose solution for MPs mitigation and biomass production. For that purpose, the occurrence of MPs from two types of WWTP effluents was analysed over one year. MPs were characterized in terms of morphology (microbead, foam, granule, irregular, filament and film), colour and size. The wastewater characterisation was followed by the removal of MP loads, using native microalgae consortia, pre-adapted to the wastewater effluent. Microalgae consortia evolved naturally through four mitigation assays, adapted to seasonal conditions, such as temperature, photoperiod, and wastewater composition. MPs were present in all the effluent samples, ranging from 52 to 233 MP L−1. The characterisation of MPs indicated a predominance of white and transparent particles, with irregular and filament shapes, mainly under 500 μm in size. The μFTIR analysis revealed that 43% of the selected particles were plastic, with a prevalence of polypropylene (PP) (34%) and polyethylene terephthalate (PET) (30 %). In the mitigation experiments, substantial biomass production was achieved (maximum of 2.6 g L−1 (d.w.)), with successful removal of MPs, ranging from 31 ± 25% to 82 ± 13%. These results show that microalgae growth in wastewater effluents efficiently promotes the removal of MPs, reducing this source of contamination in the aquatic environment, while generating valuable biomass. Additionally, the strategy employed, requires minimal control of culture conditions, simplifying the integration of these systems in real-world WWTP facilities for improved wastewater management.

Detection and characterisation of microplastics in tap water from Gauteng, South Africa

This study reports the presence, concentration, and characteristics of microplastics (MPs) in tap water in three suburbs in Gauteng Province in South Africa. Physical characterisation was conducted using stereomicroscopy and scanning electron microscopy following staining of MPs with the Rose Bengal dye. The concentrations of MPs in all samples ranged from 4.7 to 31 particles/L, with a mean of 14 ± 5.6 particles/L. Small-sized (<1 mm) and fibrous-shaped MPs were most abundant in all samples. Fibers accounted for 83.1% of MPs in samples from all the three areas, followed by fragments (12.4%), pellets/beads (3.1%), and films (1.5%), with a minor variation in the distribution of shapes and sizes in samples from each area. Raman microspectroscopy was used for chemical analysis, and five polymers were identified, namely: high-density polyethylene, polyurethane, polyethylene terephthalate, poly(hexamethylene terephtalamide), and poly(acrylamide-co-acrylic acid). C.I Pigment Red 1, C.I. Solvent Yellow 4, Potassium indigotetrasulphonate, and C.I Pigment Black 7 were the colourants detected. These colourants are carcinogenic and mutagenic and are potentially toxic to humans. The prevalence of MPs in tap water implies their inadequate removal during water treatment. For instance, the presence of poly(AM-co-AA) suggests that drinking water treatment plants may be a potential source of MPs in tap water. Other polymers, e.g., high-density polyethylene may be released from pipes during the transportation of drinking water. The estimated daily consumption of MPs from tap water was 1.2, 0.71, and 0.50 particles/kg.day for children, men, and women, respectively. The findings of this study provide evidence of the presence of MPs in drinking water in South Africa, thus giving some insights into the performance of treatment plants in removing these contaminants and a benchmark for the formulation of standard limits for the amount of MPs in drinking water.

Occurrence, distribution and sources of microplastics in typical marine recirculating aquaculture system (RAS) in China: The critical role of RAS operating time and microfilter

Industrial mariculture, a vital means of providing high quality protein to humans, is a potential source of microplastics (MPs) which have recently received increasing attention. This study investigated the occurrence and distribution of microplastics in feed, source water and recirculating aquaculture system (RAS) with long & short operating times as well as in fish from typical industrial mariculture farms in China. Results showed that microplastics occurred in all samples with the average concentration of 3.53 ± 1.39 particles/g, 0.70 ± 0.17 particles/L, 1.53 ± 0.21 particles/L and 2.21 ± 0.62 particles/individual for feed, source water, RAS and fish, respectively. Microplastics were mainly fiber in shape, blue in color and 20–500 μm in size. Compared with short operated RAS, long operating time led to higher microplastic concentration in RAS, especially that of microplastic in 20–500 μm, granular and blue. Regardless of short or long operating time, microplastics in RAS mainly gathered in culture tank, tank before microfilter and fixed-bed biological filter, and the microfilter removed efficiently the microplastic with the shape of film, granule, fragment as well as those with size > 1000 μm. As for the polymer types, polyamide (PA, 71.9 %) and polyethylene terephthalate (PET, 65.7 %) dominated in feed and source water, respectively, which may be the reason for the high proportion of PA (38.8 % and 26.4 %) and PET (31.8 % and 30.2 %) in RAS and fish. In addition, polypropylene (PP) was also detected in RAS (18.7 %) and fish (22.6 %), indicating that other plastic facilities such as PP brush carrier also made a contribution. Positive matrix factorization (PMF) model revealed three sources of MP in RAS, namely plastic facilities, industrial sewage and plastic packaging products. Our results provided a theoretical basis for the management of MP in RAS.

The significant impacts of laundry wastewater on microplastics: a case study in a residential area

Microplastics (MPs) in urban drainage are a significant source of river pollution. Laundry waste, which can contain high levels of microfibers, is a potential source of MPs in urban drainage. This study investigated the abundance and characteristics of MPs in urban drainage channels in Ketawanggede Village, Malang City, Indonesia. The research involved stages such as inorganic and organic separation using Fe2SO4.7H2O and H2O2, density-based MPs separation, and analysis of abundance, size, color, and polymer through microscopy and FTIR. Statistical testing was performed using the Kruskal-Wallis Test in RStudio. The results showed that the abundance of MPs increased with distance from the river, with the highest abundance found at location 4 (267.44 particles/L). The MPs were dominated by small particles (<1 mm), fibers (58%), and transparent (74.3%) in color. The type of polymer was mostly polypropylene (PP) and nylon. The study also found that the abundance of microfibers was significantly higher at locations 2 and 3 (where laundries were located) compared to location 1. This suggests that laundry waste is a significant source of microfibers in urban drainage.

Occurrence characteristics and risk assessment of microplastics in agricultural soils in the loess hilly gully area of Yan' an, China

Large amounts of microplastics accumulated in the soil of agricultural fields with the rapid development of mulch agriculture. The enrichment of microplastics endangered the growth of crops and food security, and it also posed ecological risks. In this study, we investigated microplastics in a typical agriculture area of Yan' an City, in the loess hilly gully area of China. The characteristics of microplastics including their abundances, sizes, and types were measured through laser direct infrared spectrometer. The potential sources of microplastics were analyzed and the risk of soil microplastic pollution was evaluated. It was elaborated that the average abundances of microplastics in soil, water, and fertilizer were 4505 ± 435 n·kg−1, 91 ± 27 n·L−1, and 39,629 ± 10,114 n·kg−1, respectively. Microplastics with particle sizes < 100 μm accounted for >90 %. The smaller the particle size, the higher the content of microplastics. The top three polymers were polyethylene (PE, 37.4 %), polyethylene terephthalate (PET, 15.0 %), and ethylene vinyl acetate (EVA, 8.9 %), respectively. Agricultural mulch, plastic film, domestic waste, surface water irrigation, and organic compost were probably the potential sources of soil microplastics. The ecological risk evaluation showed that overall sampling sites had a minor ecological risk of microplastic pollution based on their abundance, while the polymer type showed a relatively high ecological risk for the investigated agricultural soils. Polyvinylchloride (PVC) and polymethylmethacrylate (PMMA) contribute considerably to the ecological risk, and their inputs to the farmland environment should be strictly limited. There was no significant carcinogenic risk to humans. This study would provide the basic reference for the current situation and risk assessment of farmland soil microplastics pollution in the loess hilly gully area of China.

Uptake and toxicity of micro-/nanoplastics derived from naturally weathered disposable face masks in developing zebrafish: Impact of COVID-19 pandemic on aquatic life

The unprecedented proliferation of disposable face masks during the COVID-19 pandemic, coupled with their improper disposal, threatens to exacerbate the already concerning issue of plastic pollution. This study evaluates the role of environmentally weathered masks as potential sources of microplastics (MPs) and nanoplastics (NPs) and assesses their adverse impact on the early life stages of zebrafish. Experimental findings revealed that a single disposable mask could release approximately 1.79 × 109 particles, with nearly 70% measuring less than 1 μm, following 60 days of sunlight exposure and subsequent sand-induced physical abrasion. Remarkably, the MPs/NPs (MNPs) emanating from face masks have the potential to permeate the outer layer (chorion) of zebrafish embryos. Furthermore, due to their minute size, these particles can be consumed by the larvae's digestive system and subsequently circulated to other tissues, including the brain. Exposure to mask-derived MNPs at concentrations of 1 and 10 μg/L led to significant cases of developmental toxicity, incited oxidative stress, and prompted cell apoptosis. A subsequent metabolomics analysis indicated that the accumulation of these plastic particles perturbed metabolic functions in zebrafish larvae, primarily disrupting amino acid and lipid metabolism. The outcomes of this research underscore the accelerating possibility of environmental aging processes and physical abrasion in the release of MNPs from disposable face masks. Most importantly, these results shed light on the possible ecotoxicological risk posed by improperly disposed of face masks.

Stormwater outlets: A source of microplastics in coastal zones of Cape Town, South Africa

The runoff from stormwater outlets are potential sources of microplastics (MPs) in coastal zones. The characteristics and concentrations of MPs in coastal water, sediment and biota (mussels, whelks and sea urchins) were measured in summer (2020/2021) (dry season) and winter (2021) (wet season) from three sites (Camps Bay, Mouille Point and Three Anchor Bay) in Cape Town. MPs were characterised visually using a stereo microscope and chemically using spectroscopy. MP concentrations were higher in water and sediment during winter, and higher in biota in summer. Compared to control sites, MPs were higher at all impact sites sampled. MPs extracted were mainly black polyester (PEST) fibres, 1000 to 2000 μm in length averaging 0.15 MPs/L in water, 52.11 MPs/kg dry weight in sediment and 1.35 MPs/g soft tissue wet weight in biota. The results indicate that coastal stormwater systems are potential sources of MPs in the coastal environment of Cape Town.

Microplastics in groundwater: An overview of source, distribution, mobility constraints and potential health impacts during the anthropocene

Microplastics (MPs) have already been detected in various environmental matrices like soil, sediment, and surface water, and recently in groundwater also. The occurrence of MPs in groundwater depends up on the transportation through recharge and may controlled by source and local hydrogeology, and partly on the process of surface water-groundwater interaction (SW-GW). Based on the available studies, we intended to establish a hypothetical overview on the source and process-dependent occurrence of MPs in groundwater across terrestrial and coastal aquifers. Groundwater recharge from agricultural stagnant water, losing streams near dumping sites and agricultural fields, effluents from wastewater treatment plants, septic system failure etc. are the potential sources of MPs in groundwater. The factors like sea level rise and tidal pumping are among the major factors which may control the migration of MPs in coastal aquifer along with the physical and chemical properties of the aquifer media. These MPs have another ecological concern as they can adsorb persistent organic pollutants as well as heavy metals and transfer them to animal tissues through food chain. Studies are being conducted mainly focusing the MP contamination in surface water, marine environment and soil, and very limited studies are available to address the source of MPs in groundwater. However, no such study has been done on the existence, profusion, or environmental factors that contribute to MP pollution in the groundwater in relation to the present climate change scenario. Understanding the extent of MP contamination in groundwater systems is necessary for developing effective management strategies and minimizing their impact on the environment and human health. This study focusses on the source along with the controlling factors of the migration of MPs towards groundwater including the effect of climate change.

Microplastics in environment: a comprehension on sources, analytical detection, health concerns, and remediation.

Contamination of ecosystems by microplastics (MPs) has been reported intensively worldwide in the recent decade. A trend of reports indicated their presence in the atmosphere; food items and soil ecosystems are rising continuously. Literature evidenced that MPs are abundant in seawater, beach sand, drinking water, agricultural soils, wastewater treatment plant (WWTP) effluent, and the atmosphere. The greater abundance of MPs in the environment has led to their invasion of seafood, human-consumed food items such as table salts, beverages, takeout food containers, and disposable cups, marine biological lives, and creating serious health hazards in humans. Moreover, the absence of guidelines and specifications for controlling MPs in the environment makes the situation alarming, and the human toxicity data of MPs is scarce. Thereby, the toxicity assessment of MPs in humans is of greater concern. This review compiles the updated information on the potential sources of MPs in different components of the environment (viz.soil, water, and air), their analysis methods, effects on human health, and remediation methods.

Plastic rain—Atmospheric microplastics deposition in urban and peri-urban areas of Patna City, Bihar, India: Distribution, characteristics, transport, and source analysis

Evidence of atmospheric microplastics (MPs) deposition in India is scarce though reports of MPs pollution in other environmental media exist. Henceforth, this study for the first time examines and compares the abundance, characteristics, transport, and source analysis of atmospheric MPs in the urban and peri-urban areas of Patna city, Bihar, India. Wet atmospheric fallout samples were collected and analyzed for MPs deposition rate. The results showed that the mean MPs concentrations at each site were 1959.6 ± 205 (urban) and 1320.4 ± 126 (peri-urban) MPs/m2/day. The deposited MPs were mainly transparent fibers and fragments with a mean size of 347.9 ± 189.2 µm. Polyethylene terephthalate and polypropylene were the most abundant polymer found at both sites. Morphological characteristics revealed surface degradation and deposition of metal contaminants on the identified MPs. Meteorological parameters (wind direction and rainfall intensity) were significantly associated with the distribution of atmospheric MPs in the study area. The cluster mean backward trajectory suggested vehicular emissions, construction activities, and waste mismanagement as the potential sources of MPs. Findings of the present work necessitates future studies in gaining a deeper understanding of the fate, movement, and potential health hazards associated with atmospheric MPs.

Identification of microplastic fibres released from COVID-19 test swabs with Raman imaging

BackgroundCOVID-19 pandemic is not yet over, and it has been generating lots of plastic wastes that become a big concern. To catch the virus, for example, no matter via antigen or PCR test, swab is generally used for sampling. Unfortunately, the swab tip is commonly made of plastics, and thus it can be a potential source of microplastics. This study aims to propose and optimise several Raman imaging to identify the microplastic fibres released from different COVID-19 test swabs.ResultsThe results show that Raman imaging can effectively identify and visualise the microplastic fibres released from the swabs. In the meantime, on the surface of the fibres, additives such as titanium oxide particles are also captured for some brands of swabs. To increase the result certainty, scanning electron microscope (SEM) is first employed to get the morphology of the released microplastic fibres, along with Energy-dispersive X-ray spectroscopy (EDS) to confirm the presence of titanium element. Then, Raman imaging is advanced to identify and visualise the microplastics and titanium oxide particles, from different characteristic peaks in the scanning spectrum matrix. To further increase the imaging certainty, these images can be merged and cross-checked using algorithms, or the raw data from the scanning spectrum matrix can be analysed and decoded via chemometrics, such as principal component analysis (PCA). Beyond the advantages, the disadvantages of the confocal Raman imaging (affected by focal height) and algorithms (non-supervised calculation) are also discussed and intentionally corrected. In brief, the imaging analysis (particularly the combined SEM with Raman) is recommended to avoid the possible result bias that might be generated from the single spectrum analysis at a selective but random position.ConclusionsOverall, the results indicate that Raman imaging can be a useful tool to detect microplastics. The results also send us a strong warning that, if we worry about the potential microplastics contamination, we should be cautious to select the suitable COVID-19 testing kits.

Cryosphere as a temporal sink and source of microplastics in the Arctic region

Microplastics (MPs) pollution has become a serious environmental issue of growing global concern due to the increasing plastic production and usage. Under climate warming, the cryosphere, defined as the part of Earth’s layer characterized by the low temperatures and the presence of frozen water, has been experiencing significant changes. The Arctic cryosphere (e.g., sea ice, snow cover, Greenland ice sheet, permafrost) can store and release pollutants into environments, making Arctic an important temporal sink and source of MPs. Here, we summarized the distributions of MPs in Arctic snow, sea ice, seawater, rivers, and sediments, to illustrate their potential sources, transport pathways, storage and release, and possible effects in this sentinel region. Items concentrations of MPs in snow and ice varied about 1–6 orders of magnitude in different regions, which were mostly attributed to the different sampling and measurement methods, and potential sources of MPs. MPs concentrations from Arctic seawater, river/lake water, and sediments also fluctuated largely, ranging from several items of per unit to >40,000 items m−3, 100 items m−3, and 10,000 items kg−1 dw, respectively. Arctic land snow cover can be a temporal storage of MPs, with MPs deposition flux of about (4.9–14.26) × 108 items km−2 yr−1. MPs transported by rivers to Arctic ocean was estimated to be approximately 8–48 ton/yr, with discharge flux of MPs at about (1.65–9.35) × 108 items/s. Average storage of MPs in sea ice was estimated to be about 6.1×1018 items, with annual release of about 5.1×1018 items. Atmospheric transport of MPs from long-distance terrestrial sources contributed significantly to MPs deposition in Arctic land snow cover, sea ice and oceanic surface waters. Arctic Great Rivers can flow MPs into the Arctic Ocean. Sea ice can temporally store, transport and then release MPs in the surrounded environment. Ocean currents from the Atlantic brought high concentrations of MPs into the Arctic. However, there existed large uncertainties of estimation on the storage and release of MPs in Arctic cryosphere owing to the hypothesis of average MPs concentrations. Meanwhile, representatives of MPs data across the large Arctic region should be mutually verified with in situ observations and modeling. Therefore, we suggested that systematic monitoring MPs in the Arctic cryosphere, potential threats on Arctic ecosystems, and the carbon cycle under increasing Arctic warming, are urgently needed to be studied in future.

Release of microplastics from disposable face mask in tropical climate

Outbreak of COVID 19 has caused an abrupt surge in the consumption of disposable face masks around the world. WHO has stated that wearing a face mask in public reduces the chances of being exposed to COVID 19 virus. With unchecked disposal of these used masks, a new kind of pollutant has emerged in the environment. Since these masks are generally made of polypropylene and polyurethane material, they can be considered as a potential source of microplastics (MPs) in the environment. In this study, we have evaluated the release of MPs particles from these face masks (namely from N95 and surgical masks) in deionized (DI) water and tap water over the span of 1 to 180 days. More specifically, a systematic study has been carried out to see the effect of temperature on release of MPs in water. MPs particles released in tap water (837 ± 113 particles/piece in 30 days) were significantly higher than that in DI water (564 ± 37 particles/piece in 30 days). When these masks were kept at a constant temperature of 45 °C for 30 Days, highest amount of MPs release (N95 899 ± 65 particles, Surgical 1038 ± 65 particles/piece) was observed as compared to other conditions. Most of the MPs particles released were polypropylene which were transparent and white in case of N95 while for surgical mask they were found to be of blue and white colour. With the aging of masks in water, quantity of MPs release was increased with simultaneous reduction in their size. Our study indicates that these disposable face masks are emerging to be a prominent source of MPs release in the environment and more hazardous for the tropical climate.

Microplastic Hazards and Possible Mitigation

Overuse of plastic that live on in nature has created a global crisis on our ecosystem and environment. Small particles of plastic of diameter upto 5mm called microplastics are found everywhere clogging the arteries of our mother nature. Microplastics absorb organic contaminants and act as vectors of potentially hazardous chemicals in living system. To save the flora and fauna of the earth from hazards of microplastics, the potential sources of microplastics should be identified and use of plastics be controlled and if possible terminated, Plastic litters should be recycled and reprocessed. To decrease our dependency on plastics, alternatives should be found. Research on plastic recycling and finding plastic alternatives should be scaled up. Most importantly common people should be made aware of the hazards of use of plastic. Public opinion in favour of termination of plastic use would be the most powerful weapon in saving the earth from this crisis

Identification of Microplastics and Non-Microplastics Released from Masks under Environmental Conditions

Single-use plastic masks had been widely used in the background of COVID-19, which became the potential source of microplastics. This study focused on the release and characterization of microplastics and non-plastic microparticles from single-use surgical masks (SMs) under simulated environmental conditions. In this work, we found that most microplastics were released from SMs under UV exposure (120.00 ± 17.44 items/mask). Mechanical abrasion (76.00 ± 22.63 items/mask) and high temperature exposure (68.00 ± 0.00 items/mask) could also significantly promote the release of microplastics contrasted to the control groups (37.33 ± 8.33 items/mask). The main polymer types of microplastics were PP and PET. In addition, the total particles were released from masks as the order of mechanical abrasion (17.42 ± 2.25 × 103 items/mask) &gt; UV exposure (5.12 ± 1.62 × 103 items/mask) &gt; high temperature exposure (4.57 ± 3.47 × 103 items/mask) &gt; control groups (2.83 ± 1.46 × 103 items/mask). Among them, there were varied and complex non-microplastics particles (22 kinds total) detected in the experiments. This study provides help to better understand the potential risk of microplastics and different component types of non-plastic microparticles released from masks under simulated environmental conditions.

Effects of Urban Surface Roughness on Potential Sources of Microplastics in the Atmospheric Boundary Layer

Effects of Urban Surface Roughness on Potential Sources of Microplastics in the Atmospheric Boundary Layer

Microsynthetics in waters of the South American Pantanal

Microplastics are an emerging global threat to freshwater ecosystems. There is a growing number of microplastic studies in wetlands and floodplains such as the Pantanal. Microplastics in the Pantanal’s water courses, lakes, and floodplains were sampled with a plankton net in 16 locations in the Pantanal lowlands at varying distances from their potential urban sources over 2 years. Microplastics from the water samples were separated from sediments and organic matter and examined under a stereomicroscope to be identified and counted. Visual determination was then confirmed by RAMAN spectrometry. We found 730 microplastics. The average ± std microplastic concentration was 38 ± 16 x/m3, ranging between 10 and 100 x/m3. Fibres, fragments, and films represented 68%, 28%, and 4%, respectively, of the total microplastics. Surprisingly, a synthetic blue fibre of non-identified composition accounted for 51.0% of the microplastics. Other identified polymers included PP (18.2%), PET (16.9%), PVC (5.1%), PVA (4.4%) and LDPE (4.4%). The blue fibres, PP, and PET were found at all sampling locations. Microplastic concentrations varied from 27 ± 12 x/m3 to 48 ± 21 x/m3 across the sampling sites. Microplastics’ average size was 0.51 ± 0.21 mm, ranging from 0.06 to 0.97 mm. In the study area, the average seasonal concentrations varied from 34 ± 11 to 43 ± 18 x/m3 during the 2 years study period (2018–2019). In lentic environments, the median concentrations (30 x/m3) were significantly lower than in the lotic ones (40 x/m3). Urban human activities are a potential source of microplastics as the concentration of these increased significantly with the population of the nearest human agglomeration. These results indicate widespread contamination of the Pantanal waters by microplastics. Furthermore, a microsynthetic of indeterminate composition is found everywhere in the Pantanal, and more research is urgently needed to determine its composition and sources. The contamination by micropolymers and other microsynthetics will likely impact the Pantanal biota and, eventually, humans living in these floodplains.

Errors and recommended practices that should be identified to reduce suspected concentrations of microplastics in soil and groundwater: A review

Over the last decade, many studies on microplastics (MPs) have only focused on the marine environment, and scientist have recently begun to document soil and groundwater MP contamination. However, many of these studies have included errors that should be addressed. Therefore, the aim of this study is to identify multiple errors in internationally reported soil and groundwater MPs studies and to provide recommendations. Over 185 original research papers on soil and groundwater MPs published between 2017 and 2022 from seven database categories in the Web of Science were sorted. These papers were manually sorted to identify errors in (i) sample quantity, (ii) quality assurance and equipment used, (iii) microplastic identification, and (iv) microplastic classification. The majority of studies were found not to use blank samples, classified MPs incorrectly by mixing MP shapes and forms, used filters with either larger pore sizes, or materials that could be potential sources of MP. In some of these studies, the statistical package or law used for statistical analysis was not specified, with some other studies using problematic MP analysis procedures. As a remediation method to address these errors, MP studies should consider using blank soil samples and metallic filters. Statistical software packages should be used, and the statistical prerequisite laws should be verified prior to analysis. Stereo microscopes should be used simultaneously with Raman or Fourier transform infrared (FTIR) spectroscopy to identify MPs in soils and groundwater. • It is essential plastic kits are not used for storing soil and groundwater after sampling. • Accurate microplastic analysis requires at least one trip and a device blank sample each time. • Film and fragment should be classified as the same microplastics shape, not separate shapes. • A glass filter is preferable to a cellulose filter for accurate microplastics analysis. • It is critical to collect soil weight in the range of 200–1000 g for accurate microplastic analysis.