Microplastic Fragments Research Articles

Effect of different types and shapes of microplastics on the growth of lettuce

The presence of microplastics in agricultural soils has emerged as a significant environmental concern due to their persistent nature. Microplastics of different properties (i.e., types, shapes, size, concentration) are present in the environment, but the studies on the effect of microplastics having different properties are limited. Thus, this study investigated the effects of different microplastics (low-density polyethylene (LDPE) fragments, polyvinyl chloride (PVC) fragments, and LDPE fiber) in soil on the growth of lettuce (Lactuca sativa L.). Pot tests were carried out to study the effect of a range of microplastic concentrations and different shapes and types of microplastics in soil on the lettuce growth. The different growth parameters such as lettuce weight, lengths, and chlorophyll contents were measured and compared. The results showed that the adverse effects of the microplastics on the lettuce growth increased with increasing microplastic concentration. The effects of LDPE fragments and fibers on the root weights and the chlorophyll contents were microplastic shape-dependent. Also, the effects of LDPE fragments and PVC fragments on the shoot and root weights and the chlorophyll contents were microplastic type-dependent. Among the three microplastics studied, LDPE fragments tend to have greater effects on the lettuce growth than the other microplastics. Overall, the results show that the effects of microplastics on different growth parameters of lettuce can be shape- and/or type-dependent. The presence of microplastics having different properties make the understanding the effects of microplastics on plants difficult, and this necessitates further studies.

High salinity promotes the photoaging of polystyrene microplastics with humic acid in seawater

The photoaging of microplastics (MPs) accumulated in the sea can be influenced by humic acid (HA). However, the role of salinity cannot be ignored, as it may potentially disrupt the interaction between MPs and HA, thereby altering the photoaging of MPs. Herein, this study investigated how salinity influences the effect of humic acid (HA, derived from lignite) on the photoaging of polystyrene microplastics (PS MPs) in artificial and natural seawater. The results revealed that HA promoted the photoaging of PS MPs under both low (5 PSU) and high salinity (35 PSU) in light conditions (L), reflected in the formation of fragments, the production of oxygen–containing functional groups (OH, CO, and OCO), and the increase in hydrophilicity of PS MPs. Furthermore, high salinity promoted the photoaging of PS MPs with HA more significantly, as evidenced by the similar indicators and the order of oxygen/carbon atom ratio (O/C): L–HA–High (0.15) > L–HA–Low (0.10) > Unaged (0.02). Interestingly, due to the reduction of electrostatic repulsion, the adsorption of HA on photoaged PS MPs in natural and artificial high salinity seawater was 1.77 mg/g and 0.39 mg/g, respectively, which was significantly higher than those PS MPs photoaged in the low salinity seawater. Furthermore, the electron spin resonance (ESR) results confirmed that more hydroxyl radicals (OH) were generated after adsorbing HA under high salinity conditions, thus promoting the fragmentation and oxidation of PS MPs. Overall, our findings highlight the crucial role of salinity in influencing the photoaging of MPs with HA and help to assess the marine risk of MPs accurately.

Elevated temperature enhanced lethal and sublethal acute toxicity of polyethylene microplastic fragments in Daphnia magna

Microplastic (MP) pollution poses a growing concern in freshwater ecosystems, which are further threatened by global warming. Thus, this study investigated the effect of elevated temperature (25 °C) on acute toxicity of polyethylene MP fragments to Daphnia magna over a 48 h period. At the reference temperature (20 °C), MP fragments (41.88 ± 5.71 µm) induced over 70 times higher lethal toxicity than that induced by MP beads (44.50 ± 2.50 µm), with median effective concentrations (EC50) of 3.89 and 275.89 mg L−1, respectively. Elevated temperature significantly increased (p < 0.05) the lethal (EC50 = 1.88 mg L−1) and sublethal (lipid peroxidation and total antioxidant capacity) toxicity in D. magna exposed to MP fragments compared to those at the reference temperature. Additionally, the elevated temperature led to a significant increase (p < 0.05) in the bioconcentration of MP fragments in D. magna. Overall, the present study increases understanding for the ecological risk assessment of microplastics under global warming, highlights that elevated temperature can be seriously increased bioconcentration of MP fragments, leading to increased acute toxicity in D. magna.

Microplastics in the tropical Northwestern Pacific Ocean and the Indonesian seas

The abundance of microplastics fragments with sizes larger than 0.30–0.35 mm is measured during two research cruises in the tropical Northwestern Pacific Ocean and inside the Indonesian seas. The fragments are confirmed to be primarily nylon, polyester, and polyethylene etc. microplastics in the western Pacific by Fourier transform infrared spectroscopy (FT-IR), whereas dominated by polyethylene in the Indonesian seas based on Raman spectrum analyses. The abundance of the microplastics is found to be very low (<0.018 particles m−3) in the surface waters of the North Equatorial Current and the Kuroshio, suggesting no westward extension of the Great Pacific Garbage Belt and lack of microplastics accumulation due to mass convergence in the western boundary current. The abundances of the microplastics in the Makassar Strait of the Indonesian seas are found to be higher by an order of magnitude than those in the Northwestern Pacific, believed to be due to river run-offs carrying microplastics from nearby lands. The largest microplastics abundance is found in the northeastern Maluku Sea, where concurrent current measurements suggest a branch of the Indonesian Throughflow bringing accumulated microplastics from the eastern Indonesian seas into the convergent area of multiple strong currents. The study underlines the importance of ocean circulation in the microplastics distributions and transportation, and suggests the importance of high-resolution spatial mapping in the budget analysis of global microplastics distribution.

Systematic Review of Nano- and Microplastics' (NMP) Influence on the Bioaccumulation of Environmental Contaminants: Part II-Freshwater Organisms.

Nano- and microplastic fragments (NMPs) exist ubiquitously in all environmental compartments. The literature-based evidence suggests that NMPs interact with other environmental contaminants in freshwater ecosystems through sorption mechanisms, thereby playing a vector role. Chemically bound NMPs can translocate throughout the environment, reaching long distances from the contaminant discharge site. In addition, they can be ab/adsorbed by freshwater organisms. Although many studies show that NMPs can increase toxicity towards freshwater biota through the carrier role, little is known regarding their potential to influence the bioaccumulation of environmental contaminants (EC) in freshwater species. This review is part II of a systematic literature review regarding the influence of NMPs on bioaccumulation. Part I deals with terrestrial organisms and part II is devoted to freshwater organisms. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA ScR) was used for the literature search and selection. Only studies that assessed the bioaccumulation of EC in the presence of NMPs and compared this with the bioaccumulation of the isolated EC were considered. Here, we discuss the outcome of 46 papers, considering NMPs that induced an increase, induced a decrease, or caused no effect on bioaccumulation. Lastly, knowledge gaps are identified, and future directives for this area of research are discussed.

Responses of earthworms exposed to low-density polyethylene microplastic fragments

The interest in the effect of microplastics (MPs) on the terrestrial environment has been increasing recently. Different species of earthworms have been used to study the effects of MPs on different aspects of earthworm health. However, there is still a need for more studies because different studies report different effects on earthworms depending on the properties (e.g., types, shapes, sizes) of MPs in the environment and exposure conditions (e.g., exposure period). This study used Eisenia fetida as a test earthworm species to investigate the effect of different concentrations of low-density polyethylene (LDPE) MPs (≤125 μm) in soil on the growth and reproduction of earthworms. The exposure of the earthworms to the different concentrations of LDPE MPs (0–3% w/w) for 14 d and 28 d neither caused death of the earthworms nor showed significant effects on the earthworm weights in this study. The number of cocoons produced by the exposed earthworms were also similar to that of the controls (i.e., no exposure to MPs). Some previous studies reported similar results to what have been observed in this study, while some studies reported different results. On the other hand, the number of ingested MPs by the earthworms increased with increasing MPs concentrations in soil, suggesting a potential for damage to digestive tract. Also, the earthworm skin surface was damaged after exposure to MPs. The ingested MPs and the skin surface damage suggest that there is a potential for adverse effects on the earthworm growth after a longer-term exposure. Overall, the results of this study show that the effects of MPs on earthworms need to be studied using various endpoints including growth, reproduction, ingestion, and skin damage and such effects can be different depending on the exposure conditions such as MPs concentration and exposure period.

Detecting microplastics in organic-rich materials and their potential risks to earthworms in agroecosystems

Microplastics (MPs) are a major emerging contaminant in agroecosystems, due to their significant resistance to degradation in terrestrial environments. Although previous investigations have reported the harmful effects of MPs contamination on soil biological properties, still little is known about the characteristics and fate of MPs in biosolid-amended soils and their risks to soil biota, particularly earthworms. We determined microplastics’ concentration, size distribution, and chemical composition in 3 sewage sludge biosolids and 6 biosolid-amended agricultural soils. In addition, we assessed the potential short-term risks of MPs to earthworms’ (Amynthas Gracilis and Eisenia Fetida) survival rate and fitness in an environmentally relevant exposure study (28 days). Biosolid-amended soils (1000–3100 MPs kg−1 dry mass) showed ≈30 times lower MPs content than investigated biosolids (55400–73800 MPs kg−1 dry mass), with microplastic fragment to fibre ratios between 0.2 and 0.6 and 0.3–0.4 in soils and biosolids, respectively. Total MPs dry mass was also ≈19 times lower in assessed soils (12–26 mg kg−1) than biosolids (328–440 mg kg−1). On average 77% and 80% of plastic fragments had a lower dimension than 500 µm, while 50% and 67% of plastic fibres had a length of less than 1000 µm in soil and biosolid samples, respectively. Polyethylene (23.6%) was the major source of microplastic contamination in biosolid-amended soils, while polyethylene terephthalate (41.6%) showed the highest concentration in biosolid samples. Spiked polyethylene MPs did not show any significant effect on earthworms’ survival rate (93–99%). However, biosolid application significantly (P < 0.05) decreased survival rate of Eisenia Fetida (81%) but showed no significant effect on Amynthas Gracilis (93%). Biosolid amendment significantly (P < 0.05) decreased earthworms’ growth rate, with higher impact on Eisenia Fetida than Amynthas Gracilis, while there were no significant differences between control and microplastic spiked treatments. The overall decrease in MPs concentration of earthworm casts, compared with initial MPs concentrations in soil, indicated that the investigated species did not bioaccumulate MPs during the exposure experiment.

Subterranean transport of microplastics as evidenced in karst springs and their characterization using Raman spectroscopy

The increasing use of plastic materials has led to accumulation of large amounts of plastic waste in environment and a global challenge to be tackled with. The natural process of macro-plastics aging generates a multitude of secondary microplastic fragments accumulating in all areas of the planet. The pollution with microplastics of large water bodies, such as rivers, seas and oceans was already proven, but the presence of microplastics even in karst spring water was not reported yet. In this study, Raman micro-spectroscopy was used to confirm the presence of microplastics in the spring water samples collected from two rural karst springs in the Apuseni Mountains (Țarina and Josani), North-Western Romania. Two sets of water samples of 1000 L collected in spring time 2021 and one in autumn 2021 were filtered and analyzed. Using the Python programming language and combining two separate Raman databases, one for plastics and the other for pigments, we established a customized database to unambiguously identify the type of plastic and pigment present in the discovered micro-fragments. The generated reference pigment-plastic spectra were compared to those of potential microplastics found on filters and Pearson's coefficient was used to measure the level of similarity. The presence of microplastics in karst spring waters was confirmed and a quantitative estimation expressed as number of fragments or fibers per liter was 0.034 in Josani and 0.06 in Țarina karst spring. Five months later sampling (autumn 2021) revealed 0.05 microplastics per liter. The spectral results revealed that most microplastics found were dominated by polyethylene terephthalate (PET), followed by polypropylene and interestingly, abundant blue micro-fragments were identified according to their copper phthalocyanine pigments (pigment Blue 15) or indigo carmine (pigment Blue 63) characteristic spectral fingerprints, which surpassed the inherent spectral background level characteristic for the Raman spectra of naturally contaminated waste micro-samples. Their origin in mountain karst spring waters and potential decrease in time is discussed.

The ovarian-related effects of polystyrene nanoplastics on human ovarian granulosa cells and female mice

Nanoplastics (NPs) have recently emerged in the context of global plastic pollution. They may be more toxic than macroplastics litter and microplastic fragments due to its abundances, tiny sizes, and cellular accessibility. The female reproductive toxicity of NPs has been widely documented for aquatic animals, but their effects and underlying mechanisms remain poorly understood in mammals. This study aimed to explore the effects of NPs on female reproduction using human ovarian granulosa cells (GCs) and female mice. The accumulation of polystyrene NPs (PS-NPs) in human granulosa-like tumor cells (KGN cells) and the ovaries of female Balb/c mice were evaluated by exposure to fluorescent PS-NPs. Proliferation and apoptosis, reactive oxygen species (ROS), and Hippo signaling pathway-related factors were analyzed in KGN cells. In addition, fertility rate, litter size, ovarian weight and microstructure, follicle development, serum level of anti-Mullerian hormone, and apoptosis in ovaries were examined in female mice. Here, the PS-NPs can penetrate the KGN cells and accumulate in the ovaries. In vitro, 100 μg/ml PS-NPs inhibited proliferation, induced apoptosis, accumulated ROS, activated three key regulators of the Hippo signaling pathway (MST1, LATS1, and YAP1), and downregulated the mRNA levels of CTGF and Cyr61 in KGN cells. Furthermore, salidroside, an antioxidative compound extracted from Rhodiola rosea, alleviated the damage of PS-NPs to KGN and inhibited the activation of the Hippo signal pathway. In vivo, exposure to 1 mg/day PS-NPs resulted in decreased fertility, abnormal ovarian function, and increased ovarian apoptosis in female mice. Overall, our data suggest that PS-NPs cause granulosa cell apoptosis and affect ovarian functions, leading to reduced fertility in female mice, by inducing oxidative stress and dysregulating the Hippo pathway.

An analytical computed microtomography methodology for identification of microplastic fragments in aqueous media

AbstractThe impact of microplastics (MPs) on the environment is a major concern that affects not only marine life but also the entire ecosystem. MPs are defined as tiny artificial polymer‐based particles, measuring less than 5 mm in length. The impact of these compounds on human health concerns the metabolic alterations, reproductive disorders, neurological disorders, and hormone‐dependent tumors. Due to the problems involved in the improper disposal of this material in nature (in beaches, rivers, lakes, ponds, and oceans), and also, all the risks of MPs both for the ecosystem and for all beings alive, it became extremely important to develop a methodology that makes it possible to quantify this material when present in aqueous media. Therefore, the aim of this study is to present a methodology developed in the laboratory to quantify MP fragments present in an aqueous media. For this, phantoms were developed with plastic fragments from 0.18 to 0.71 mm, in diameter, which were later analyzed using the computed microtomography technique (microCT). The microCT is a non‐invasive imaging technique that uses X‐rays to produce detailed 3D images of the internal structure of an object. The results showed a good contrast pattern, and the quantitative analysis represented satisfactory results for all samples, with relative error below 20%.

No effects of plasticized microplastics on the body condition and reproduction of a marine fish

Abstract This study experimentally explored the influence of periodic consumption of polystyrene (PS) microplastic fragments on the body condition and fitness of a tropical marine fish. Adult damselfish, Acanthochromis polyacanthus, were pulse fed microplastic fragments bound with one of two different common plasticizers [di-2-ethylhexyl phthalate (DEHP), di-2-ethylhexyl terephthalate (DEHT)] together with virgin-plastic and no-plastic controls. Ingestion of plastic over a 150d period had no detectable effect on growth, indices of body condition, or gonadosomatic indices. Histology of the liver showed no detrimental effects of ingesting any of the plastic treatments on hepatocyte density or vacuolation. Plastic consumption had no effect on the number of clutches produced over the breeding period, the number of eggs, or the survival of embryos. It is believed that the relatively inert nature of PS, the low amount of plasticizers leached from the fragments and fast gut through-put times meant fish were exposed to low levels of toxic compounds.

The invasive red swamp crayfish (Procambarus clarkii) as a bioindicator of microplastic pollution: Insights from Lake Candia (northwestern Italy)

Microplastic pollution has become pervasive. Identifying a bioindicator species to track the occurrence and effects of microplastics (MPs) on ecosystems is crucial for determining their impact on the environment. The digestive tract of Procambarus clarkii was thought to be of interest for investigating MPs accumulation in freshwater organisms. Our hypothesis was that the same type of MPs found in abiotic compartments (water and sediment) could be found in P. clarkii, which would make it an ideal candidate for use as a bioindicator of MP pollution in freshwater ecosystems. Water, sediment, and P. clarkii specimens were collected from four sites in a lentic ecosystem (Lake Candia; northwestern Italy) for two consecutive years (2021–2022). The mean MPs abundance was 1.75 ± 0.95 items/m3 in 2021 and 2 ± 0.81 items/m3 in 2022 in the water samples and 6.75 ± 1.5 items/kg and 8 ± 0.81 items/kg in the sediment samples in 2021 and 2022, respectively. In 2021, the average was 0.06 ± 0.07 items/g in the males and 0.05 ± 0.05 items/g in the females; in 2022, the average was 0.04 ± 0.05 items/g and 0.05 ± 0.06 items/g in the males and the females, respectively. MP fibers and fragments (black, white, blue, light blue) of polypropylene and polyethylene terephthalate were found in the biotic and the abiotic compartments. The generalized linear mixed model revealed that the number of items/g was predicted only by total weight: the lowest number of items/g was recorded for crayfish with the highest weight probably due to the feeding habits of P. clarkii. Our findings suggest that the invasive P. clarkii (smaller individuals, in particular) could be a good candidate bioindicator for MP pollution since the same type of MP items were recorded in the abiotic compartments. Further research is needed to better understand the feeding behavior of P. clarkii and the dynamics of MPs in aquatic ecosystems.

Methods for controlled preparation and dosing of microplastic fragments in bioassays

Microplastic fragments (microfragments) are among the most abundant microplastic shapes found in marine ecosystems throughout the world. Due to their limited commercial availability, microfragments are rarely used in laboratory experiments. Here a novel method of microfragment production has been developed and validated. Polyethylene and polypropylene plastic stock (2 and 3 mm thick respectively) was ground using a cryomill, washed, and rinsed through a stack of sieves. Microfragments were prepared at three distinct size classes (53–150, 150–300, 300–1000 μm) and were confirmed to be accurate and consistent in size. Employing a novel ice cap dosing technique, microfragments were accurately dosed into experimental vials while excluding headspace, facilitating particle suspension without the aid of chemical surfactants. A proof of principle ingestion experiment confirmed the bioavailability of 53–150 μm polyethylene microfragments to brine shrimp Artemia sp. Together, these methods provide a controlled way to produce and dose microplastic fragments for experimental and analytical research.

First quantification and chemical characterization of atmospheric microplastics observed in Seoul, South Korea

This study is the first report on atmospheric microplastics (MPs) observed in five outdoor environments, including an urban forest, a business center, commercial areas, and a public transportation hub in Seoul, South Korea. Air samples were collected using an active air pump sampler for 24 h in each area only on days without rainfall. All observed microplastics are secondary microplastics, in the form of irregularly-shaped fragments or fibers produced through various degradation processes, rather than being primarily produced like microbeads. The abundance of atmospheric MPs varied depending on the environment (i.e., region, height, and time) from 0.33 to 1.21 MP m-3, with the average number of MPs being 0.72 MP m-3 (standard deviation ± 0.39). MPs in the urban forest was observed to be 27% lower in abundance than that in the urban center which is ∼3 km away. The central business district was observed to have a 25% higher abundance during weekdays than on weekends. Our results show the ubiquity of MPs in various areas from high-rise buildings to forests tens of kilometers away from their direct sources, and a positive correlation between the abundance of MP and human activity. Morphologically, the fragment type (87.4%) predominated over the fiber type (12.6%), and chemically, polypropylene (PP) and polyethylene terephthalate (PET) components accounted for 65% of the total MP. PP polymers were found in all observation sites and contributed to 59% of the total MP fragments. The observed fibrous MPs were mainly composed of PET (72.7%) and PP (18.2%) polymers. Compared to other large cities (Shanghai, Beijing, Paris), Seoul is exposed to low levels of atmospheric MPs and high proportions of PP polymers. This study is limited to atmospheric MPs observed in summer and further investigation of MPs is needed to comprehensively understand the distribution and cycle of MPs based on long-term monitoring of atmospheric MPs.

Maternal Effect of Polyethylene Microplastic Fragments Containing Benzophenone-3 in Different Ages and Broods of Daphnia Magna

The maternal effect of microplastics (MPs) toxicity is likely influenced by age and brood of test species. This study investigated the maternal effect of polyethylene MP fragments (18.23 ± 8.02μm) with benzophenone-3 (BP-3; 2.89 ± 0.20% w/w) on chronic toxicity to Daphnia magna over two generations. Neonate (< 24h old) and adult (5 d old) daphnids in the F0 generation were exposed until 21 d old, then first and third brood neonates in the F1 generation were recovered in clean M4 medium for 21 d. Higher chronic toxicity and maternal effect of MP/BP-3 fragments were observed in the adult group compared with the neonate group, reducing growth and reproduction in both F0 and F1 generations. First brood neonates in the F1 generation showed a higher maternal effect of MP/BP-3 fragments than third brood ones, resulting in enhanced growth and reproduction relative to the control. This study provided insights into the ecological risk of MPs containing plastic additives in the natural environment.

Microplastics in Landfill Bodies: Abundance, Spatial Distribution and Effect of Landfill Age

Almost a quarter of the plastic produced in Europe still ends up in landfills. In addition to the loss of valuable resources, this leads to the generation and accumulation of microplastics in landfills. The microplastics abundance in the refuse and their spatial distribution in the landfill body have not been practically studied. In the current work, changes in the abundance and characteristics of microplastics in landfill refuse from 3 age sections of the Lapės regional landfill, Lithuania, to a depth of 10–20 m were studied. A microplastics abundance of up to 55 particles/g or 52.8 g/kg was found. The lowest microplastics abundance was found in the old section, while the highest in the young (numerical) and the middle-aged (mass) sections. Moreover, microplastics abundance increased with the age of landfilled waste and depth, which may reflect the fragmentation of microplastics and their transport. Polyethylene and polypropylene were the dominant polymer types in all sections, while films were the dominant shape. The carbonyl index of PE microplastics was calculated to monitor microplastics oxidation. The analysis showed an increase of carbonyl index with landfill depth and landfill age, proving the intensive degradation of microplastics. Thus, landfills are large reservoirs of microplastics and their potential sources.

Assessment of Microplastics in the Surface Water of Sitio Pulo, Navotas, Metro Manila

Microplastics are synthetic polymer particles with a length of 5 mm or less with no well-defined lower boundary. These debris particles are known to affect marine and aquatic organisms which poses a threat to biodiversity and marine resources. In this study, the isolated microplastic from the coastal and lagoon surface waters of Sitio Pulo is described. Sitio Pulo is a barrier island mangrove sanctuary located at Brgy. Tanza I, Navotas City surrounded by Manila Bay. The samples collected last July 4 and 25, 2019, were isolated, profiled, and analyzed. A total of four hundred forty-nine (449) microplastic fragments were isolated from the surface water samples with a median length of 1.096 (IQR 0.809–1.578) mm. The isolated microplastics exhibit roundness, whiteness, and yellowing indicating signs of mechanical, chemical and photodegradation. It is also noted the putative effects of the weather disturbances in accelerating the discharge of nascent microplastics in Manila Bay. The isolated microplastic composition includes the commodity polymers polyethylene (PE) and polypropylene (PP). The presence of microplastics in the surface waters of Sitio Pulo reflects the worsening plastic pollution problem in Metro Manila.

MICROPLASTICS IN NATURAL WATER: SOURCES AND DETERMINATION

The paper is devoted for origin of microplastics in aquatic environment and possible methods of characterization and analysis. According to US National Oceanic and Atmospheric Administration, microplastics are synthetic organic polymer particles with a size less than 5 mm. Microplastics pollution is a significant ecological problem in the world. A lot of surface waters are significantly polluted by various types of microplastics. These pollutants were found in rivers, lakes, oceans, sediments, wastewater, drinking water and bottled water. But in Ukraine microplastic problem of surface water do not meet the interest of scientists and ecological organizations. Disintegration of plastic waste is one of the main sources of microplastics in water. But there are a lot of other sources of primary and secondary microplastics, including components personal care products, industrial abrasives, abrasion from car tires, paint failure, industrial processes, textile washing, at-sea losses, etc. Microplastics can harm ecosystems and cause many health problems for different organisms, including problems with feeding and digestion, endocrine disruptions and changes in cellular functions. In general, health effects and environmental impacts are dependent on the size of the microplastic particles and chemical structure of these polymers. Thus, it is very important to understand chemical composition, physical forms, transport in environment and fragmentation of microplastics due to the need to predict possible exposure effects. There are a lot of methods for characterization and analysis of microplastics, but all of them have some disadvantages. Microplastics determination is often especially difficult for water with low microplastics content due to very large volumes of water samples and very small mass of separated plastics.

Identifikasi Kelimpahan Mikroplastik Sungai Batanghari Wilayah Nipah Panjang Kabupaten Tanjung Jabung Timur

One of the biggest environmental issues today is plastic waste. This waste cannot be avoided and continues to increase which in its decomposition takes 50-100 years and will be fragmented into smaller forms called microplastics. Microplastic measuring &lt; 5 mm with various shapes. The people of the Nipah Panjang area dispose of plastic waste into the Batanghari River which is likely to cause microplastic content. To determine the number of microplastics, it is necessary to identify the abundance of microplastics found in the Nipah Panjang area on the Batanghari River using quantitative methods. The tool used is Planktonet mesh 150 with a diameter of 20 cm. The sampling process was carried out for one day with two samplings, namely in the morning at low tide at 09.00-11.00 WIB and in the afternoon at high tide at 15.00 WIB. The study's results were sampling in the morning at low tide with 327 microplastic particles and the highest in the afternoon at high tide, namely 443 microplastic particles. The temperature in the morning and evening ranges from 29°C - 32°C. The results showed that four types of microplastics were found, namely the type of fiber, filament, fragment, and granule. From the four locations of Sungai Air samples, the most microplastic fragments were found with a total of 353 particles, the second most were filament types with a capacity of 191 particles, the third type of fiber with a total of 186 particles, and the least types of granules with a total of 40 particles. Microplastic at low tide is lower than at high tide. The abundance of microplastics from the four sampling locations of river water is 25,666.67 particles/m3.

Identification of factors influencing the microplastic distribution in agricultural soil on Hainan Island

Microplastics (MPs) are ubiquitous in agricultural soils, but to what extent and how environmental factors determine the source and fate of MPs in agricultural soils is not clear. In this study, Hainan Island, which has different climatic conditions, altitudes, and land uses across the island, was selected to investigate the MPs abundance and the shape, size, color, and polymer type of the MPs in agricultural soils. The main focus was on the role of land use type and the identification of environmental influencing factors. The results showed that MPs were detected in all the soil samples across the island, with an abundance range of 20 to 6790 items kg−1 and an average of 417 items kg−1. Fragments (46.8 %), MPs smaller than 0.5 mm (37.8 %), black MPs (48.3 %), and polypropylene MPs (56.8 %) were observed as the dominant MPs species. Significantly higher MPs abundance was found in mulched arable land, and higher contents of fibers and fragments were observed in woodland and paddy lands, respectively. With correlation and redundancy analyses, soil pH, soil organic matter content, and average annual temperature were found to be the main factors influencing the biotic/abiotic fragmentation of MPs. The regional population density, including tourism represented by the night light index, affects the input process of MPs. MPs transport and deposition were found to be affected by altitude, annual precipitation, and soil moisture content. This study represents the first large-scale study of MPs contamination in island agricultural soils and provides important data on the distribution, transport, and fate of MPs.