Microplastics In Water Research Articles

Effect of microplastics in water and aquatic systems

Surging dismissal of plastics into water resources results in the splintered debris generating microscopic particles called microplastics. The reduced size of microplastic makes it easier for intake by aquatic organisms resulting in amassing of noxious wastes, thereby disturbing their physiological functions. Microplastics are abundantly available and exhibit high propensity for interrelating with the ecosystem thereby disrupting the biogenic flora and fauna. About 71% of the earth surface is occupied by oceans, which holds 97% of the earth’s water. The remaining 3% is present as water in ponds, streams, glaciers, ice caps, and as water vapor in the atmosphere. Microplastics can accumulate harmful pollutants from the surroundings thereby acting as transport vectors; and simultaneously can leach out chemicals (additives). Plastics in marine undergo splintering and shriveling to form micro/nanoparticles owing to the mechanical and photochemical processes accelerated by waves and sunlight, respectively. Microplastics differ in color and density, considering the type of polymers, and are generally classified according to their origins, i.e., primary and secondary. About 54.5% of microplastics floating in the ocean are polyethylene, and 16.5% are polypropylene, and the rest includes polyvinyl chloride, polystyrene, polyester, and polyamides. Polyethylene and polypropylene due to its lower density in comparison with marine water floats and affect the oceanic surfaces while materials having higher density sink affecting seafloor. The effects of plastic debris in the water and aquatic systems from various literature and on how COVID-19 has become a reason for microplastic pollution are reviewed in this paper.Graphical abstract

Comparative analysis of microplastic content in water, sediments, and digestive traces of sea urchin Diadema setosum (Leske, 1778) on Untung Jawa Island and Tidung Island, Seribu Islands, Jakarta

This study aims to compare the abundance and types of microplastics in water, sediments, and digestive tracts of sea urchins Diadema setosum, in Untung Jawa Island and Tidung Island, Seribu Islands. Samples of sea urchins, water, and sediment were taken from 15 different locations based on the location of the biota colony. Samples of the digestive tracts of sea urchins were analyzed by dissolving them at 65% HNO3, water samples (20 l) were filtered with a 300 μm plankton net, and sediment samples (200 g) were dried in the oven first, then each sample was given NaCl to saturate. Each sample (1 ml) is placed in the Sedgwick Rafter Chamber to be examined under a microscope. The results showed that the abundance of microplastic in Untung Jawa Island was higher at 99.88 ± 1.79 particles l−1 in water, 110,737.77 ± 4,197.61 particles Kg−1 particles in sediment, and 2,175.55 ± 584.26 particles Ind−1 in the digestive tract of sea urchins. On Tidung Island microplastic abundance contained in the water amounted to 87.4 ± 9.61 particles l−1, the sediment of 87,626.66 ± 4,957.00 particles Kg−1, and in the digestive tract of sea urchins to 1,786.66 ± 451.17 particles Ind−1.

Preparation of a reference material for microplastics in water\u2014evaluation of homogeneity

Validation of analytical methods for measurements of microplastics (MP) is severely hampered because of a general lack of reference materials, RM. There is a great need to develop such reference materials. This study presents a concept of three-component kit with immobilised MP in solid NaCl, a surfactant and clean water that can be applied for the production of many types of MP RMs. As proof of concept, an RM for polyethylene terephthalate (PET) particles in water was prepared and evaluated for its homogeneity. The particles ranged from 30 μm (Feretmin) to about 200 μm adapted by wet sieving. A specific number of PET particles were immobilized in about 0.29 g of solid NaCl by freeze-drying 1 mL of a NaCl suspension. By using manual and automated counting, twenty reconstituted 1-L water samples were evaluated for homogeneity with respect to number of PET particles from 30 μm to > 200 μm/L of water. The number of particles was 730 ± 120 (mean ± one standard deviation (SD); n = 10) and 865 ± 155 particles (n = 10) obtained by optical microscopy in two independent laboratories. This corresponded to relative SDs of 16.4 and 17.9% and a mean of 797 ± 151 particles (18.9% RSD, for n = 20). Homogeneity studies of the NaCl carrier without reconstitution resulted in 794 ± 60 particles (7.5% RSD). The homogeneity of PET in the salt carrier was also evaluated directly with respect to mass of PET per vial using an ultra-micro balance. An average mass of 293 ± 41 μg of PET was obtained (14, % RSD for n = 14). Micrographs were recorded to demonstrate the absence of major sources of contamination of the RM components. Information about the particle size distribution and particle shapes was obtained by laser diffraction (LD) and dynamic image analysis (DIA). In addition, the identity of the PET polymer was confirmed by Raman and FT-IR spectroscopy. The RM was developed for a large-scale inter-laboratory comparison of PET particles in water (ILC). Based on the homogeneity results, the material was found to be sufficiently homogeneous to be of meaningful use in the ILC. In a 3-day process, more than 500 samples of PET particles in the NaCl carrier were prepared with good potential for further upscaling with respect to the number of vials or with other kinds of polymers. The stability of PET was not evaluated but it was deemed to be stable for the duration of the ILC.

Behavior of Microplastics in Inland Waters: Aggregation, Settlement, and Transport.

Inland waters are the main medium transporting microplastics to the ocean. Aggregation, vertical settlement, and horizontal transport will occur when microplastics enter the inland waterbodies. This paper reviews these behaviors of microplastics in inland waters and their influencing factors. The aggregation of microplastics were divided into homogeneous aggregation and heterogeneous aggregation, which are critical for the settlement of microplastics. The settlement of microplastics in inland water bodies is influenced by microplastic properties (size, density, and shapes) and environmental conditions (microorganisms, sedimental properties, hydraulic conditions, and so on). Horizontal transport of microplastics in water is influenced by hydrologic conditions, rainfall, river morphologies, dams, vegetation, etc. Future perspectives including laboratory simulations and numerical models involving multiple factors, the behaviors of degradable plastics, and the influence of hydrologic conditions have been proposed.

Engineered technologies for the separation and degradation of microplastics in water: A review

In recent years, the presence of the group of contaminants, termed as microplastics (MPs) has been recognized as significant water pollutants with considerable potential for exerting adverse impacts on human health and wildlife. Natural attenuation has practically no effect while conventional treatment processes are not capable of entirely removing MPs which are reported to accumulate in the environment, in organisms in the aquatic food web and, potentially reaching humans. This in-depth review critically evaluates the state-of-the-art engineered technologies suitable for the separation and degradation of microplastics in water with potential for real-scale application. The outcomes of the review confirmed that very limited number of studies are reported in this field, the majority from recent years and have focused on using phase-changing processes, including coagulation-flocculation, flotation, and membrane processes. A few other studies have reported the use of chemical or biological digestion, and even fewer, engineered removal using biodegradation, wet oxidation, and advanced oxidation processes. This paper focuses on the type of MPs being removed, the process conditions and the outcomes reported in research literature. The emerging trends in the field are also highlighted as well as the identification of current knowledge gaps and future research directions along with perceptive comments and recommendations related to the application of available technologies for water treatment.

Chia seed-assisted separation and detection of polyvinyl chloride microplastics in water via gas chromatography mass spectrometry

Chia seeds were used to significantly improve the separation efficiency of polyvinyl chloride (PVC) microplastics from water samples via centrifugation. Upon hydration, the mucilage of chia seeds were able to capture PVC microplastics with sizes ranging from tens to hundreds of micrometers. Since PVC microplastics contained di-2-etylhexyl phthalate (DEHP) as a plasticizer (verified via Fourier transform infrared spectrometry), DEHP was used as an indicator in the subsequent quantification via gas chromatography – mass spectrometry (GC-MS) analysis. Specifically after verifying the DEHP peak in the GC spectrum using DEHP reference standard as a positive control, the GC spectral area of that peak was used to quantify the amount of DEHP in the sample. Using nominal operation settings at 10 min and 1000 rpm with 100 mg of chia seeds, the separation efficiency could be improved by 5 times (500%) as compared to the absence of chia seeds. Furthermore, chia seeds were also compatible with simulated synthetic wastewater samples. Most importantly, the use of chia seeds did not interfere with GC-MS quantification protocol and accuracy. The result suggested the proposed method can be used as a simple screening tool of microplastics entering wastewater treatment plant, even though a series of follow-up studies are needed in future.

Optical detection of microplastics in water.

Unfortunately, the plastic pollution increases at an exponential rate and drastically endangers the marine ecosystem. According to World Health Organization (WHO), microplastics in drinking water have become a concern and may be a risk to human health. One of the major efforts to fight against this problem is developing easy-to-use, low-cost, portable microplastic detection systems. To address this issue, here, we present our prototype device based on an optical system that can help detect the microplastics in water. This system that costs less than $370 is essentially a low-cost Raman spectrometer. It includes a collimated laser (5mW), a sample holder, a notch filter, a diffraction grating, and a CCD sensor all integrated in a 3D printed case. Our experiments show that our system is capable of detecting microplastics in water having a concentration less than 0.015% w/v. We believe that the designed portable device can find a widespread use all over the world to monitor the microplastic content in an easier and cost-effective manner.

Long-term trends of microplastics in seawater and farmed oysters in the Maowei Sea, China.

Microplastic pollution in marine environments and organisms has received a great deal of international attention. However, the long-term field studies of microplastics are rare. Here, we assessed annual variation in microplastic abundance in the Maowei Sea, a classic mariculture bay in southern China, and analyzed the long-term accumulation in oyster tissues. U-shaped time trends of microplastics in water were observed from January to December in 2018 in the estuarine region, inner bay, and mouth bay sites, representing an inverse relationship with the local rainfall patterns. The common microplastic particles in Maowei Sea are PET/PE fibers, and polystyrene foams, which are mainly related to textile pollution and fishery activities. After one year of continuous monitoring, we did not find accumulation of microplastics in the whole soft tissues of oyster after 10% KOH digestion. No significant correlation of microplastic abundances between water and oysters was observed. The microplastic abundance in oyster was correlated with some environmental variables (i.e. salinity, pH, nutrients and total organic carbon) of the surrounding water following Spearman correlation analysis. The microplastic levels in oysters could probably be influenced by the environmental variables.

Synthesis of Nano-Composite Ag/TiO2 for Polyethylene Microplastic Degradation Applications

The aim of this research is to synthesize Ag/TiO2 nano-composites to study their ability to degrade microplastics in water, followed by varying size of microplastic particles as pollutants in drinking water. The method used for synthesizing Ag/TiO2 is Photo Assisted Deposition (PAD). Characterizations done to determine the difference between TiO2 and Ag/TiO2 were SEM-EDX and UV-Vis DRS. Polyethylene microplastics were selected as samples in this study. The variation of microplastic size used is 100-125, 125-150, and 150-250 micrometers with initial concentrations of 100 ppm. Magnetic stirrers used at a rotational speed of 2000 rpm during the degradation process with a UV lamp irradiation. The addition of the Ag dopant has a good effect in microplastic degradation, where the percentage of degradation reaches 100% within 120 minutes of irradiation at an initial concentration of 100 ppm. An initial concentration of 100 ppm obtained the best percent degradation at particle size 125-150 micrometers, where 100% degradation achieved at 90 minutes irradiation.

水环境中微塑料的污染现状、生态风险和未来展望

水环境中微塑料的污染现状、生态风险和未来展望

Size distribution measurement of microplastics using a temporally and spatially resolved inductively coupled plasma optical emission spectrometer (ICP-OES)

We studied microplastics in water using a temporally and spatially resolved ICP-OES with an inverted-type torch.

Microplastic Consumption and Its Effect on Respiration Rate and Motility of Calanus helgolandicus From the Marmara Sea

Consumption rates of polystyrene microplastics (beads of 6, 12, and 26 μm diameter) and their effects on energy metabolism and motor activity of the copepodCalanus helgolandicusliving in the Marmara Sea were investigated. All sizes of microplastic particles were actively consumed and excreted via fecal pellets, however, copepods displayed a significant preference for beads sized 6 μm. In a mixture of algae and microplastics beads of 6 μm, microplastics consumption rates linearly (r2= 0.78,n= 154) increased 800 times from 50.8 ± 17.3 to 8,612 ± 5,972 beads ind–1day–1with an increase in bead concentration from 10 to 44,000 beads ml–1. The total and basal metabolic rates as well as time spent swimming forC. helgolandicus, decreased 1.7, 1.8 and about 3-fold, respectively after 7–8 days exposure to microplastic treatments, which was similar to the metabolism and activity of starving animals in filtered water. In copepods consuming microplastics, all vital parameters decreased on the first day of exposure, indicating either accelerated starvation, probably due to increased losses of energy and biological matter in the formation of fecal pellets and/or traumatic/toxic effects of the polystyrene beads on the copepods. Our data from laboratory experiments indicate that the presence of large concentrations of microplastics in water, even when mixed with algae, lowered energy metabolism levels ofC. helgolandicus.

Microplastic Presence in Sediment and Water of a Lagoon Bordering the Urban Agglomeration of Lagos, Southwest Nigeria

Microplastics are a fast-emerging group of contaminants. Their worldwide occurrence in water, sediment, and aquatic fauna raises questions and concerns as to their probable effects on aquatic life and ecology. This study investigates for the first time presence, abundance, and types of microplastics in water and sediment from a lagoon bordering the large urban agglomeration of Lagos in Nigeria, and renders additional information about the sediment composition. Water and sediment samples were collected from four locations in the Lagos Lagoon and a tributary. The abundance and distribution of microplastics in four range classes were determined for the sampled locations. Plastic particles were counted using digital microscopy, and identified with Fourier Transform-Infrared Spectroscopy (FTIR) and pyrolysis Gas Chromatography–Mass Spectrometry (GC-MS). The abundance of microplastics ranged from 310–2319 particles/kg in sediment, and 139–303 particles/L in water. The large discrepancy in the sediments can be explained by sediment characteristics as more microplastics were detected in the fine-grained sediments of Makoko. Fibres were the predominant shape found in all samples followed by fragments and few films. Fibres were more abundant in water (92.6%) than in sediments (32.5%), while more fragments and foils occurred in sediments. The most commonly used polymers polypropylene and polyethylene were also the most detected ones in both matrices. Compared to other studies in Nigeria, our findings especially in the coarser sediments were lower while the fine-grained site revealed similar results.

Treatment of microplastics in water by anodic oxidation: A case study for polystyrene.

Water pollution by microplastics (MPs) is a contemporary issue which has recently gained lots of attentions. Despite this, very limited studies were conducted on the degradation of MPs. In this paper, we reported the treatment of synthetic mono-dispersed suspension of MPs by using electrooxidation (EO) process. MPs synthetic solution was prepared with distilled water and a commercial polystyrene solution containing a surfactant. In addition to anode material, different operating parameters were investigated such as current intensity, anode surface, electrolyte type, electrolyte concentration, and reaction time. The obtained results revealed that the EO process can degrade 58±21% of MPs in 1h. Analysis of the operating parameters showed that the current intensity, anode material, electrolyte type, and electrolyte concentration substantially affected the MPs removal efficiency, whereas anode surface area had a negligible effect. In addition, dynamic light scattering analysis was performed to evaluate the size distribution of MPs during the degradation. The combination of dynamic light scattering, scanning electron microscopy, total organic carbon, and Fourier-transform infrared spectroscopy results suggested that the MPs did not break into smaller particles and they degrade directly into gaseous products. This work demonstrated that EO is a promising process for degradation of MPs in water without production of any wastes or by-products.

Distributions of Microplastics in Surface Water, Fish, and Sediment in the Vicinity of a Sewage Treatment Plant

Microplastics are ubiquitously found in freshwater and marine environments worldwide. In particular, wastewater treatment plants (WWTPs) or sewage treatment plants (STPs) have been recognized as a main source of microplastics in the receiving freshwater. However, only a few studies have been conducted to examine the impact of these facilities on receiving waters. In this study, we investigated the distribution of microplastics in surface water, fish, and sediment near a sewage treatment plant (STP) in the Tanchon stream, one of the main tributaries flowing into the Han River, Korea. The concentration of microplastics in water varied spatially and temporarily, ranging between 5.3 and 87.3 particles/m3 (31.4 ± 28.5 particles/m3). In fish, the concentration in upstream and downstream sites was 7.3 ± 7.3 and 12.4 ± 17.9 particles/fish, respectively. Spatially, the downstream site was the most polluted with microplastics in water and fish. The concentration of microplastics was positively correlated with fish body length and weight. In sediment, microplastic concentration in upstream and downstream sites was 493.1 ± 136.0 and 380.0 ± 144.2 particles/kg, respectively. The contribution of upstream to the microplastic load in downstream was 15.8% in dry season (April), which was higher than that of STP effluent and Yangjaechon creek. Meanwhile, the highest load was observed in STP effluent (5.1%) in rainy season (August). Microplastics were more abundant in water in the rainy season (37.4 ± 37.0 particles/m3) than in the dry season (28.2 ± 22.2 particles/m3). Polyethylene (49%) and polypropylene (18%) were the most abundant polymer types in water, fish, and sediment. Regarding shape of microplastics, fragments were dominant (95%) over fiber and film in water, fish, and sediment.

Microplastic pollution in water, sediment, and specific tissues of crayfish (Procambarus clarkii) within two different breeding modes in Jianli, Hubei province, China.

This study investigates the occurrence and distribution of microplastics in water, sediment, and crayfish samples within pond and rice-crayfish co-culture breeding modes in Jianli prefecture, China. Microplastics in environmental and biological samples were systematically extracted by CaCl2 solution, digested by H2O2 and KOH, and identified by μ-FTIR. A cleansing treatment for crayfish was performed in pure water before dissection and microplastic accumulation in different tissues (gill, stomach, gut, and flesh) of non-cleansed and cleansed crayfish were compared. The average microplastic abundances were 1.3±0.1-2.5±0.1 particles/L, 0.03±0.01-0.04±0.02 particles/g, and 0.17±0.07-0.92±0.19 particles/individual in water, sediment, and crayfish samples, respectively. Microplastics were detected in all studied crayfish tissues, except the flesh. There were no significant differences in microplastic abundances in water (P=0.82), sediment (P=0.90), and crayfish (P=0.47 for non-cleansed samples; P=0.30 for cleansed samples) between two breeding modes despite the detection of relatively higher microplastic abundances in the samples from the pond breeding mode. Microplastic accumulation in non-cleansed crayfish stomachs and guts (0.71±0.18 particles/individual) was higher (P<0.01) than that recorded in their gills (0.13±0.06 particles/individual). Moreover, microplastics present in the stomachs and guts of cleansed crayfish were significantly less abundant (P<0.01) than in non-cleansed crayfish, although this was not observed in the gills (P=0.99). The majority of microplastic particles in this study had fiber-like shapes, blue and transparent colors, a size smaller than 1mm, and polymer types of PP:PE and PE. The results demonstrate that microplastics in the environment can accumulate in the internal tissues of crayfish, which may pose a potential risk to humans through food consumption without the removal of the gills, stomach, and guts. This study provides valuable information for understanding microplastic accumulation in the different tissues of crayfish and the potential risk of human exposure to microplastics from crayfish as a food supplement.

Microplastics in freshwater ecosystems: a recent review of occurrence, analysis, potential impacts, and research needs

The utilization of plastics has now become a threat to the environment as it generates microplastic particles (<5 mm in size). The increasing studies on the occurrence of microplastics in different environmental compartments have raised concern about the potential effects on ecosystems and living organisms. Of these, numerous studies are focused on marine environments. The occurrence of microplastics is recently extended to the freshwater environments, including river systems, streams, lakes, pond, creek, and estuarine rivers. This paper overviews the current knowledge and research findings on the occurrence of microplastics in water, sediment, and fish in freshwater environments. The review also covers the adopted methodology and impacts of microplastics to the ecosystem. Future perspectives are discussed as well in this review.

Silent Scourge: Microplastics in Water, Food, and Air

Silent Scourge: Microplastics in Water, Food, and Air

Accumulation and distribution of microplastics in the sediment and coastal water samples of Chabahar Bay in the Oman Sea, Iran

Frequency, distribution, color, and types of microplastics (<5 mm) in water and sediment of Chabahar Bay in southeastern Iran was investigated in 10 stations. Density of microplastics in water samples was between 86 and 362 particles/L (average density 218 ± 17 particle/L). In the sediment, microplastic density was between 112 and 468 particles/L (average density of 262 ± 17 particle/kg). The highest concentrations of microplastics were in stations adjacent to urban, commercial, recreational, and fishing sites. The most abundant forms in surface water and sediment were fragments (42.34%) and fibers (32.22%). Highest frequency colors were black, transparent, and white, respectively. A fourier transform infrared (FT-IR) spectrometer was used to determine micro plastic composition. Polyethylene, polyethylene terephthalate and nylon were detected. Polyethylene, a common packaging material made up 38% of the total polymers. Polyethylene terephthalate, used in clothing, liquid and food containers was found at 29% of the total microplastics.

Water column circulation drives microplastic distribution in the Martínez-Baker channels; A large fjord ecosystem in Chilean Patagonia

We investigated the distribution of microplastics in the water column along a large remote estuarine system located between the Northern and Southern Patagonian Ice Fields in Chilean Patagonia, and connected with the Pacific Ocean through the Gulf of Penas. Microplastic particles were found in all samples, with abundances ranging from 0.1 to 7 particles/m3. Polymers identified were principally acrylics, PET, and cellophane.The average abundance of microplastics in surface waters was similar along the whole estuary (0.4 ± 0.3 particles/m3) with acrylics and epoxy resins being more abundant near Caleta Tortel, the only small village in the area. The observed higher abundance of microplastics in the deeper waters towards the Gulf of Penas points to intrusions of subsurface waters transporting plastic particles from the ocean into the channel system. This underlines the potential of ocean currents in transporting plastic pollution into pristine fjords and channels in Chilean Patagonia.