Microplastics In Sediment Samples Research Articles

Analysis of the Abundance and Diversity of Microplastic Contamination in Ekas Bay Cultivation Areas

Ekas Bay is a semi-enclosed bay and estuary in the southern part of Lombok Island. Ekas Bay has an area of 5,312.68 hectares, although it is not very wide, this bay has its own uniqueness and is relatively protected from waves because it is located inland. In Ekas Bay itself, two river estuaries are found, namely the Awang River Estuary and the Kelongkong River Estuary. The existence of these two river estuaries has a negative impact on the condition of the waters of Ekas Bay because residue from household activities is carried away by the river current, one of which is plastic waste. The presence of microplastics on ocean coasts has a negative impact on sea water quality and the life of marine biota, microplastics cannot evaporate or degrade by themselves, microplastics will accumulate in sea water and the body parts of marine biota. This research aims to identify the type and abundance of microplastics in the Ekas Bay floating net cage area and the results obtained in water samples were that the abundance of microplastics at point A was 49.44 par/L, point B was 55.76 par/L and point C was 40.40 par /L. The abundance of microplastics in sediment samples at point A was 12.25 par/L, point B was 10.8 par/L and point C was 11.01 par/L.

The contamination of in situ archaeological remains: A pilot analysis of microplastics in sediment samples using μFTIR

BackgroundMicroplastics (MPs) are found in all environments: aquatic, airborne, and terrestrial. While their presence is not disputed, their potential impacts are not yet known. ObjectiveTo undertake a pilot analysis of MP contamination in archaeological sediment samples, taken in the late 1980s from two archaeological excavation sites in the historic city of York (UK) as well as contemporary sources close to the same sites, with respect to the presence (if any), levels, and characteristics of any particles identified. MethodsThis study analysed pre-digested sediment samples as follows: n = 3 from Queens Hotel (QH) site and n = 3 Wellington Row (WR) contemporary core-source, and n = 3 QH and n = 3 WR archival-source samples, alongside procedural controls (n = 8), using μFTIR spectroscopy (size limitation of 5 μm) to detect and characterise any MPs present. ResultsIn total, 66 MP particles consisting of 16 MP polymer types were identified across both site and contemporary/archived samples. The highest levels of MP particles, 20,588 MP/kg was identified at the lowest sample depth (∼7.35 m) at archived WR, 5910 MP/kg in the mid depth layer (∼5.85 m) at the contemporary QH site. Of the MPs detected in sediment samples overall, polytetrafluoroethylene (PTFE), polybutylene sulfone (PSU), and polypropylene: polyethylene (PE:PP) copolymer polymer types were most abundant; mainly fragmented and irregular shape. ConclusionsThis is believed to be the first evidence of MP contamination in archaeological sediment (or soil) samples with polymers and size ranges measured and while accounting for procedural blanks. These results support the phenomenon of transport of MPs within archaeological stratigraphy, and the characterisation of types, shapes and size ranges identified therein. Through contamination, MPs may compromise the scientific value of archaeological deposits, and environmental proxies suspended within significant sediment, and as such represent a new consideration in the dynamism of, as well as arguments for preserving, archaeological deposits in situ.

Abundance, characteristics and risk assessment of microplastics in aquatic sediments: A comparative study in the Yellow River and Yellow Sea

The occurrence of microplastics (MPs) in aquatic ecosystems has become an increasingly serious threat to public health. Marine sediments are considered the final recipients of all microplastic pollution from inland rivers, however, whether and how the MPs differ in these two ecosystems remains poorly known due to the divergent MPs detection methods employed in previous studies. Here, we investigated the abundance, size, and types of MPs in sediment samples from the Yellow River and Yellow Sea using laser direct infrared (LDIR), and assessed their ecological risks. The abundance of MPs in the Yellow Sea is 2.9 times higher than that in the Yellow River, with an average abundance of 54813.2 ± 19355.9 and 18780.2 ± 9951.8 particles·kg−1 (dry sediment), respectively. Notably, the predominant polymer types in both sediment environments were silicone, fluororubber, and polypropylene (PP). MPs with sizes < 100 μm accounted for > 90 % of the total MPs number. Risk assessment demonstrated all the sediment environments exhibited high ecological risks. The dominance of small MPs highlighted the importance of using a method with high resolution to delineate the truthful status of MP pollution.

Hydrostatic pressure drives microbe-mediated biodegradation of microplastics in surface sediments of deep reservoirs: Novel findings from hydrostatic pressure simulation experiments

Microplastics originate from the physical, chemical, or biological degradation of plastics in the environment. Once ingested by organisms at the bottom of the food chain, microplastics are passed on to organisms at higher trophic levels, posing a threat to human health. The distribution of microplastics and the metabolic pathways involved in their microbial degradation in surface sediments of drinking water reservoirs are still poorly understood. This study analyzed the occurrence patterns of microplastics and microbial community structure associated with microplastic biodegradation in surface sediments from a deep reservoir at various hydrostatic pressures. Based on the results of Fourier-transform and laser direct infrared spectroscopy, elevating the pressure resulted in altered sizes and shapes of microplastics in sediment samples with the presence of microorganisms. The influence of hydrostatic pressure on small-sized microplastics (20–500 μm) was pronounced. For instance, high pressure accelerated the breakdown of fibers, pellets, and fragments into smaller-sized microplastics. In particular, the mean size of polyethylene terephthalate microplastics decreased from 425.78 μm at atmospheric pressure to 366.62 μm at 0.7 Mpa. Metagenomic analysis revealed an increase in the relative abundances of plastic-degrading genera, such as Rhodococcus, Flavobacterium, and Aspergillus, in response to elevated pressures. Eight functional genes for biodegradation of polystyrene, polyethylene, and polyethylene terephthalate microplastics were annotated, including paaK, ladA, tphA3. Of these, tphA3 gene abundance was negatively influenced by hydrostatic pressure, providing direct evidence for the pathway by which microbial metabolism of polyethylene terephthalate led to decreased microplastic size under high pressure conditions. This study presents novel insights into hydrostatic pressure-driven microbial community structure, functional gene abundance, and key metabolic pathways associated with biodegradation of microplastics in reservoir sediments.

Microplastics Records from the Southern Ocean Sediments

ABSTRACT The study records the extent of microplastics distribution in the surficial sediments of the Southern Ocean. This represents the first study of microplastics in the sediments of Prydz Bay, Southern Ocean. Prydz Bay is the largest embayment located in the Indian Ocean Sector of the Southern Ocean and receives sediments supplied by the Lambert Glacier/Amery Ice Shelf, draining approximately 10% of the total ice volume of Antarctica. It is an important site of circumpolar deep water (CDW) and Antarctic bottom water (AABW) formation. This study focuses on the distribution of microplastics in the sediments of the Prydz Bay, Southern Ocean with special reference to the ecological risk factor of these microplastics. The type distribution of microplastics revealed percent content as bead > fiber > fragment. Ecological risk factors (CF and PLI) of microplastics in sediment samples revealed a minor to major risk of these pollutants in the analyzed environment. Statistical analyses such as principal component analysis (PCA), ANOVA, Tukey's HSD test, and correlation analysis were performed to highlight the interrelationship of MPN with CF, PLI, pH, TOC, and sediment texture. The levels of microplastic pollution in the Prydz Bay are significant on a local scale, particularly around research stations. This report underlines the immediacy of microplastic pollution management in the Southern Ocean to maintain the serenity of this pristine marine habitat. So further research on the information of microplastics policy discussions to develop appropriate management responses.

Occurrence and spatial distribution of microplastics in sediment and fish along the Persian Gulf-a case study: Bushehr Province, Iran.

Microplastics (MPs) contamination in the marine environment is a global threat. The present study is the first to comprehensively investigate the MPs contamination in the marine environment in Bushehr province along the Persian Gulf. For this purpose, 16 stations were selected along the coast and 10 fish samples were collected. The results obtained from MPs in sediment samples indicate the mean abundance of MPs in different sediment samples was 57.19Particles/Kg. The dominant MPs color in sediment samples was black, accounting for 47.54%, followed by white (36.07%). As for MPs in fish, the highest MPs digested in different fish samples were 9. In addition, over 83.3% of MPs observed in fishes were black followed by red and blue (6.67%). Overall, the presence of MPs in fish and sediment can be attributed to improper disposal of industrial effluents; an efficient measurement is required in order to improve the quality of the marine environment.

Identification Of Microplastics Content in Sediment, Water and Digestive Channel of Milkfish (Chanos chanos) in Sidoarjo Pond

Microplastics are a form of new pollution that the Indonesian people are not aware of. The factors for the entry of microplastics into pond waters are water sources, anthropogenic activities, and pond cleanliness. The purpose of this study was to determine the abundance of microplastics, the color and shape of microplastics, and the types of microplastic polymers found in sediment, water, and the digestive tract of milkfish (Chanos chanos) in Sidoarjo ponds. The average abundance of microplastics in sediment samples obtained from semi-intensive ponds is 300 particles per 50 grams, while the sediment samples from traditional ponds are 613 particles per 50 grams. The average abundance of microplastics in the semi-intensive pond water samples was 2.1 particles per 20 liters and in traditional ponds was 2.3 particles per 20 liters. The average abundance of microplastics in the milkfish (Chanos chanos) samples from the Semi-Intensive Pond was as many as 6 particles per tail, while the Traditional Pond had 9.5 particles per tail. In this study, four colors of microplastics were found, namely blue, black, red, and transparent, while the microplastics obtained were fiber, fragment, and filament. The types of microplastic polymers encountered in this study were dominated by polyamide or nylon polymers. In sediment samples from both ponds, we found the presence of Polyamide or Nylon polymers, namely Polystyrene and Polyamide or Nylon, and in the digestive tract of milkfish (Chanos chanos), namely Polyamide or Nylon.

Quantification of Microplastics by Pyrolysis Coupled with Gas Chromatography and Mass Spectrometry in Sediments: Challenges and Implications

Pyrolysis-GC/MS is increasingly used to quantify microplastics (MP) in environmental samples. In general, prior to analysis, purification steps are carried out to reduce the environmental matrix in sediment samples. The conventionally used protocol of density separation followed by digestion of organic matter does not allow for complete isolation of MP from the associated organic and mineral matter. Among the pyrolysis products used as indicator compounds for plastic polymers, some may originate from other substances present in the environmental samples. In this paper, the indicator compounds are reviewed for the most common polymers: PE, PP, PS, PET and PVC and selected taking into account potential interactions with substances present in environmental matrices. Even after a purification step, a residual mineral fraction remains in a sediment sample, including matrix effects. This effect may be positive or negative, depending on the investigated polymer and is thus important to consider when using Pyr-GC/MS for the quantification of MP in sediment samples. It also shows that no external calibration can be used to reliably quantify MP in such samples and that the use of internal standards is compulsory.

Physical and anthropogenic drivers shaping the spatial distribution of microplastics in the marine sediments of Chilean fjords

Several studies have focused on the presence and distribution of microplastics within the water column of coastal waters, but the dynamics of these particles in sediments have received little attention. Here we examine the concentrations and characteristics of microplastics in sediment samples collected from 35 stations within the Inner Sea of Chiloé, Chilean Patagonia. Current velocity, grain size, intensity of salmon farming activities, and human population density were all evaluated as factors potentially explaining concentrations and distribution of microplastic particles within these sediments. Microplastics were detected in all samples, with the highest abundance represented by fibers (88%), fragments (10%) and films (2%). Across the sampled sites, microplastic concentrations averaged 72.2 ± 32.4 (SD) items per kg dw (dry weight) sediment, with the principal polymers identified as polyethylene terephthalate (PET), acrylic, polypropylene (PP) and polyurethane (PUR). Approximately 40% of the variability in distribution and abundance of microplastics was explained by current velocity combined with proximity and intensity of local salmon production activities. SynopsisMarine currents and aquaculture intensity explain abundance and dynamics of microplastics in marine sediments.

Hydrologic controls on the accumulation of different sized microplastics in the streambed sediments downstream of a wastewater treatment plant (Catalonia, Spain)

Wastewater treatment plants (WWTPs) act as a point source of microplastics (MPs) to freshwater ecosystems. Although MP abundance has been linked to high-density population areas, the mechanisms of how river hydrodynamics and particle size influence MP accumulation in streams are still largely unknown. This study investigated the spatial distribution of MPs within streambed sediments downstream of a WWTP effluent in Cànoves stream (Montseny, Catalonia) during baseflow conditions. MP concentrations from an upstream control site were compared to the WWTP bypass that added untreated wastewater at times when stream discharge exceeded capacity. The 450 m section investigated downstream of the WWTP consisted of three geomorphically altered sub-reaches interspersed between three unaltered buffer sub-reaches, each ∼75 m that provided a range in hydrologic conditions. Measurements of MP characteristics, hydrogeomorphic variables, and fine particles were simultaneously taken. MPs were quantified following the Nile red fluorescence method for large (>64 µm) and small (10–64 µm) particles. MPs in sediment samples downstream of the WWTP were mainly fragments with a higher abundance of small MPs (85 particles/g of sediment) vs large MPs (9 particles/g of sediment). While the abundance of large MPs in streambed sediments decreased with distance from the WWTP point source, the abundance of small MPs increased. Furthermore, the area of small MPs decreased with distance from the WWTP. MPs were most abundant at the WWTP bypass, suggesting these infrequent inputs during storm events represent an important source of MPs to the stream. Higher MP abundance coincided with increased organic matter content and smaller sediment grain sizes. Overall, our results present significant findings that could help explain differences in transport and accumulation patterns of MPs that influence their retention times in streambeds, suggesting a combination of preferential filtration in the streambed sediments, and fragmentation of larger particles.

Microplastics retention by reeds in freshwater environment

Microplastic pollution has recently gained increasing attention. The accumulation of microplastics in plants has been confirmed in the marine environment. However, the extent of the microplastic retention in freshwater plants is still unknown. In this study, sediment and plant samples from six reed farms in the wetland of East Dongting Lake were collected and analyzed. The abundance of microplastics in the sediment of reed farms varied from 125.7 to 1219.5 items/kg dry weight (dw), with an average of 511.2 ± 295.0 items/kg. Moreover, different levels of microplastic abundance were found in reeds from 0 to 14 items/individual. The abundance of microplastics in sediment samples was moderate compared to that worldwide and higher than that in other regions of Dongting Lake. The microplastic pollution level was significantly higher in the reed vegetation belt than that in other sampling positions. On the basis of the distribution and characteristics of the collected microplastics, lake water and fishery are suggested as important sources of microplastics. Furthermore, the factors influencing microplastic retention in the reeds are discussed. This study, as the first direct evidence demonstrating that freshwater reeds tend to accumulate microplastics, constitutes valuable reference for future research.

Horizontal and vertical distribution of microplastics in the Wuliangsuhai Lake sediment, northern China

Microplastics are ubiquitous in the environment, sediments in the water body are considered as the sink of microplastics, but its accumulation and change trend have received little attention. We assessed the concentrations of microplastics in sediment samples collected in Wuliangsuhai Lake. The abundance of microplastics (0–6 cm) in surface sediment ranged from 16.5 to 72.4 particles 100 g−1 dry weight. The results show that the abundance, type and size of microplastics in surface sediment of different functional areas are different. Four sampling points were selected to investigate the vertical distribution of microplastics. The abundance of microplastics exhibited a clear decreasing trend with increased sediment depth, the abundance of microplastics in deep sediments is much less. This result shows that when estimating the storage of microplastics in sediments, if only considered the surface sediments, the assessment of microplastic storage worldwide might be underestimated.

Microplastic Occurrences in Sediments Collected from Marmara Sea-Istanbul, Turkey.

Microplastics are persistent, synthetic polymers that have managed to spread even to the most remote places on earth. Studies reporting on the abundance of microplastics have recently increased worldwide, which has raised environmental concerns among scientific communities. Nevertheless, evidence of microplastic contamination from Turkey is limited even though the location is a critical point and the population is higher than most countries in the region. Thus, we aimed to detect microplastics in sediment samples collected from the Marmara Sea in Istanbul-Turkey. In this study, fourteen sediment samples were collected and sub-sampled, then plastic debris was extracted, quantified and characterized by the morphology and polymer structure. The result revealed that all of the samples contained microplastics, and their concentrations ranged between 0.3 and 85.6g/kg sediment, and the most abundant plastic types were acrylonitrile butadiene styrene, ethylene vinyl acetate, and polystyrene.

Identification and distribution of microplastics in the sediments and surface waters of Anzali Wetland in the Southwest Caspian Sea, Northern Iran

The occurrence, abundance and distribution of microplastics (MPs) were studied in sediments and surface waters of the Anzali coastal wetland, southwest of the Caspian Sea. Sediment and surface water samples were taken at 11 and 6 stations in June 2018 and January 2019 respectively. The abundances of MPs in sediment samples were 140–2820 and 113–3690 items/kg dry weight while in surface waters were 0.40–4.41 and 0.19–2.85 items/m3 in June and January respectively. Fiber was the most common shape, followed by fragment and film. Red, black and blue were the most frequent colors. Particles 1–2 mm were the dominant size. SEM/EDS and ATR-FTIR analyses were used to identify MPs. Polypropylene, polyethylene and polyester were the most frequently found polymers. Our results highlighted the widespread dispersion of MPs in Anzali Wetland which in turn might be a pathway of MPs pollution transporter to the adjacent and connected Caspian Sea.

Microplastics in sediments from Amazon rivers, Brazil

We assessed the concentrations of microplastics in sediment samples collected in seven sites from Solimões, Negro and Amazon rivers, upstream and downstream the metropolitan region of Manaus. Concentrations ranged from 417 to 8178 particles/kg of dried sediment (microplastics: 0.063–5 mm), and from 0 to 5725 particles/kg of dried sediment (microplastics: 0.063–1 mm). The highest microplastics concentrations were observed in samples from shallow water (water depth of 5–7 m) sites with lower water velocity of the Negro river surrounding Manaus, and the lowest concentration in farthest sample collected in deeper zone (water depth of 34 m) of the Amazon river around 110 km downstream Manaus. The variation of microplastics concentrations within the studied area can be related to hydraulic characteristics defining the erosive-depositional behavior of the sampling sites and their proximity to Manaus. Our results represent the first report to show the ubiquitous presence and widespread distribution of microplastics in sediments from the lower Solimões, lower Negro and upper Amazon rivers.

Microplastic contamination on the lower Chao Phraya: Abundance, characteristic and interaction with heavy metals

While a large number of studies on microplastics (MPs) in the western hemisphere have been performed, few studies are available in the eastern hemisphere, especially in Southeast Asia. In this study, the abundance of MPs in water and sediment samples from the Chao Phraya River at the Tha Pra Chan area, Thailand, was investigated. Water samples were collected by a manta trawl, and sediment samples were collected by a Van Veen grab sampler. The average number and concentration of MPs in water samples were 80 ± 65 items/m³ and 53.3 ± 58.4 mg/m³, respectively. The average number and concentration of MPs in sediment samples were 91 ± 13 items/kg and 4.9 ± 3.4 mg/kg, respectively. The main morphologies of MPs were fragments and fibers, mostly white. Polypropylene (PP) was the dominant polymer type found in both water and sediment. Moreover, the content of heavy metals (Cr, Cu, Ni, and Pb) on MPs was extracted by aqua regia solution and analyzed by ICP-OES. Results show high concentrations of Pb and Cu adsorbed on MPs in the study area. In brief, this study suggests that there are high levels of MPs in the water and sediments of the Chao Phraya River at the Tha Pra Chan area.

Distribution characteristics of microplastics in the seawater and sediment: A case study in Jiaozhou Bay, China

As a newly identified form of pollutant in the ocean, microplastics are receiving more and more attention from researchers. In order to evaluate the potential impact of microplastics, it is important to have comprehensive knowledge of the current microplastic situation. This study analyzed the abundance, polymer type, size, shape and color of microplastics in the seawater and sediments of Jiaozhou Bay, China, a semi-enclosed bay highly affected by surrounding human activities. Qualitative and quantitative analysis of microplastics were carried out using stereo microscope and attenuated total reflection micro-Fourier transform infrared spectrometer (ATR-μ-FT-IR). The abundance of microplastics in the bay seawater samples ranged between 20 items/m3 and 120 items/m3. The abundance of microplastics in sediment samples in the bay were between 7 items/kg d.w. and 25 items/kg d.w. The microplastics were mainly in black and blue colors with fiber being the dominant shape in all samples. All microplastics identified were smaller than 4 mm in this study. Polyethylene terephthalate (PET) was the main type of microplastics, followed by polypropylene (PP) and polyethylene (PE). Both the abundance and types of microplastics show positive correlations between the seawater and sediment samples. Microplastic polymer types in the bay showed close match to the polymer types in the estuaries. Relatively higher abundance of microplastics tended to be found in the area where there were residual currents and sediment transport trends. Our study showed riverine input is an important contributor to the microplastics in the bay and physical factors such as residual currents would greatly affect the aggregation of microplastics.

Microplastics in sediments and fish from the Red Sea coast at Jeddah (Saudi Arabia)

Environmental contextMillions of tons of plastic debris are present in the marine environment. This study addresses the issue of microplastics in nearshore sediment and fish sampled from the Saudi coastal waters of the Red Sea. The results show that the sediments of all analysed stations contained microplastics, and microplastic particles were detected in almost half of the 140 sampled fish. AbstractThe amounts of microplastics in sediment samples obtained from four stations along the Jeddah coast were shown to range from not detected to 119particleskg−1 wet sediment. Four classes of microplastic particles in the sediment, that is, fragments, granules, foams and fibres, were characterised by fluorescence microscopy. Microplastics of various forms and sizes were also identified in 44% of the 140 sampled fish (6 local species) in amounts ranging from not detected to 30 microplastic particles per individual. Polyethylene terephthalate and vinyl chloride-vinyl acetate copolymers were the dominant polymer types in the sediment samples identified by Fourier-transform infrared spectroscopy (FTIR) analysis, while polystyrene, polyethylene and polyester were the dominant polymer types detected in fish. FTIR analysis showed that the most detected fibres were made of polyester. The results of this study emphasise that microplastic pollution represents an emerging threat to the marine environment of the Red Sea. The results of this study provide useful background information for further investigations and provide an accurate overview of the microplastics distribution in the marine environment of the Saudi Red Sea.

Identification and Quantification of Microplastics in Wastewater Using Focal Plane Array-Based Reflectance Micro-FT-IR Imaging.

Microplastics (<5 mm) have been documented in environmental samples on a global scale. While these pollutants may enter aquatic environments via wastewater treatment facilities, the abundance of microplastics in these matrices has not been investigated. Although efficient methods for the analysis of microplastics in sediment samples and marine organisms have been published, no methods have been developed for detecting these pollutants within organic-rich wastewater samples. In addition, there is no standardized method for analyzing microplastics isolated from environmental samples. In many cases, part of the identification protocol relies on visual selection before analysis, which is open to bias. In order to address this, a new method for the analysis of microplastics in wastewater was developed. A pretreatment step using 30% hydrogen peroxide (H2O2) was employed to remove biogenic material, and focal plane array (FPA)-based reflectance micro-Fourier-transform (FT-IR) imaging was shown to successfully image and identify different microplastic types (polyethylene, polypropylene, nylon-6, polyvinyl chloride, polystyrene). Microplastic-spiked wastewater samples were used to validate the methodology, resulting in a robust protocol which was nonselective and reproducible (the overall success identification rate was 98.33%). The use of FPA-based micro-FT-IR spectroscopy also provides a considerable reduction in analysis time compared with previous methods, since samples that could take several days to be mapped using a single-element detector can now be imaged in less than 9 h (circular filter with a diameter of 47 mm). This method for identifying and quantifying microplastics in wastewater is likely to provide an essential tool for further research into the pathways by which microplastics enter the environment.