Ship-based visual observation underestimates plastic debris in marine surface water.

Visual observation surveys from ships are commonly used for monitoring floating marine debris, but their detection performance has not yet been fully verified. Here, simultaneous visual observation surveys and surface trawling were conducted in three coastal areas of South Korea, each with distinct characteristics. The extent of floating debris missed by visual observations was assessed, and the characteristics of overlooked debris were identified.

Qualitative and quantitative assessment of microplastics derived from antifouling paint in effluent from ship hull hydroblasting and their emission into the marine environment.

This study focused on microplastic (MP) contamination originating from ship paint, particularly during the hydroblasting of ship hull, to understand the emission characteristics of MPs into the marine environment. We evaluated paint particles generated from the hydroblasting of an ocean-going vessel based on their number, size, polymer type, and mass. Hydroblasting a vessel produced 4.

Habitat use of loggerhead (Caretta caretta) and green (Chelonia mydas) turtles at the northern limit of their distribution range of the Northwest Pacific Ocean.

Verifying habitats, including the foraging and nesting areas for sea turtles, enables an understanding of their spatial ecology and successful planning of their conservation and management strategies. Recently, the observation frequency and bycatch of loggerhead (Caretta caretta) and green (Chelonia mydas) turtles have increased in the northern limit of their distribution range, in the northern part of the East China Sea and East (Japan) Sea. We conducted satellite tracking to investigate the habitat use of seven loggerhead and eight green turtles from June 2016 to August 2022 in this area, where little is known about their spatial ecology.

Experimental study on color and texture as cues for plastic debris ingestion by captive sea turtles.

Sea turtles face considerable risks from ingesting marine debris. They are primarily visual feeders, so color may be important for identifying food suitability or enhancing prey detection. Here, we investigated the impacts of color and texture on foraging behavior in relation to plastic consumption.

Occurrence and characteristics of microplastics in greywater from a research vessel.

The discharge of greywater from ships, an uncounted sea-based source of microplastics (MPs), is a growing concern. Yet, empirical data on MPs from this source are currently limited. Here, the abundances and characteristics of MPs in greywater from a research vessel were investigated according to water usage type (e.

Intra-annual variation in microplastics in mussels (Mytilus galloprovincialis) inhabiting an urbanized bay of South Korea.

This study investigated the presence of microplastics (MPs) in mussels from an urbanized bay in Korea, focusing on intra-annual variation. The average MP concentration was 0.36 ± 0.

Selective attachment of prokaryotes and emergence of potentially pathogenic prokaryotes on four plastic surfaces: Adhesion study in a natural marine environment.

This study employed 16S rRNA metabarcoding to establish the diversity of prokaryotic communities and specific characteristics of potentially pathogenic prokaryotic primary colonizers of four plastic materials (EPS, expanded polystyrene; PE, polyethylene; PP, polypropylene; and PET, polyethylene terephthalate). Bacteria inhabiting plastic and seawater differ; thus, distinct changes in the attached prokaryotic community were observed over an exposure time of 21 days, specifically on Days 3, 6, 9, and 12-21. Frist colonizers were Gammaproteobacteria and Alphaproteobacteria; Bacilli and Clostridia represented secondary colonizers.

Spatial distribution and historical trend of microplastic pollution in sediments from enclosed bays of South Korea.

Seafloor sediments are an important sink for microplastics (MPs), and the vertical profile of MP accumulation in a sediment core represents historical pollution trends. In this study, MP (20-5000 μm) pollution in surface sediments of urban, aquaculture, and environmental preservation sites in South Korea was evaluated, and the historical trend was investigated using age-dated core sediments from the urban and aquaculture sites. The abundance of MPs ranked in the order of urban, aquaculture, and environmental preservation sites.

The effects of environmental Microplastic on wharf roach (Ligia exotica): A Multi-Omics approach.

This is the first report to evaluate the potential effects of microplastics (MPs) on wild wharf roaches (Ligia exotica) in a shoreline habitant. L. exotica is an important plastic detritus consumer in coastal area.

Identification and quantification of photodegradation products of disposed expanded polystyrene buoy used in aquaculture.

This study investigated the chemicals extracted from an EPS buoy used in aquaculture, which were subsequently collected from a recycling center. It was observed that the chemicals generated upon photodegradation make disposed buoys more toxic. Analysis of the extracted chemicals revealed the presence of 37 compounds, with four compounds quantitatively determined.

Fragmentation of nano- and microplastics from virgin- and additive-containing polypropylene by accelerated photooxidation.

Plastic is ubiquitous in the environment, where it gradually weathers and fragments into nanoplastics (NPs) and microplastics (MPs); however, the weathering process and fragmentation rate are poorly understood. In this study, we quantitatively determined the abundances and size distributions of NPs and MPs produced from virgin polypropylene (PP) and additive-containing PP (PPa) sheets via photooxidation with water in a simulated sunlight chamber followed by vortexing. The fragmentation rate of PP and PPa were approximately 1.

Distribution, compositional characteristics, and historical pollution records of microplastics in tidal flats of South Korea.

Studies on distribution of microplastics (MPs) in sediments of tidal flats are relatively scarce compared to other coastal areas. In this study, spatial and vertical distributions and compositions of MPs in tidal flat sediments along the west coast of Korea were investigated. The abundance of MPs in surface and core sediments ranged from 20 to 325 and 14 to 483 particles per 50 g dry weight, respectively.

Microplastic emission characteristics of stormwater runoff in an urban area: Intra-event variability and influencing factors.

Stormwater runoff is considered a major pathway for land-based microplastic transportation to aquatic environments. By applying time-weighted stormwater sampling at stormwater outlets from industrial and residential catchments, we investigated the emission characteristics and loads (number- and mass-based) of microplastics to aquatic environments through urban stormwater runoff during rainfall events. Microplastics were detected in stormwater runoff from industrial and residential areas in the concentration range of 68-568 n/L and 54-639 n/L, respectively.

Plastic debris as a mobile source of additive chemicals in marine environments: In-situ evidence.

Plastic debris can act as a source of hazardous chemicals in the ocean, but the significance of its role in the environment is not yet known. To address this question, a comprehensive field study of highly contaminated and non-contaminated islands was conducted. Comparison of the plastic additive hexabromocyclododecanes and ubiquitous contaminants polychlorinated biphenyls in marine invertebrates showed that the load of stranded plastics plays a significant role in the bioaccumulation of plastic additives in the marine debris-contaminated island.

Toward a long-term monitoring program for seawater plastic pollution in the north Pacific Ocean: Review and global comparison.

Through a literature survey and meta-data analysis, monitoring methods and contamination levels of marine micro- and macroplastics in seawater were compared between the North Pacific and the world's other ocean basins. The minimum cut-off size in sampling and/or analysis of microplastics was crucial to the comparison of monitoring data. The North Pacific was most actively monitored for microplastics and showed comparatively high levels in the global context, while the Mediterranean Sea was most frequently monitored for macroplastics.

The fragmentation of nano- and microplastic particles from thermoplastics accelerated by simulated-sunlight-mediated photooxidation.

The plastic debris that washes ashore and litters the shoreline often undergoes weathering under sunlight exposure, such that it fragments to form nanoplastics and microplastics, but the fragmentation rate for many thermoplastics is unknown. In this study, three major thermoplastics were exposed to simulated sunlight in an accelerated weathering chamber to evaluate the speed of photooxidation-induced fragmentation. The initiation of photooxidation-induced fragmentation extrapolated from the accelerated weathering chamber to real sunlight exposure in South Korea followed the order of PS (< 1 year) > PP (< 2 years) > LDPE (> 3 years).

Spatial distribution and temporal trends of classical and emerging persistent organic pollutants (POPs) in black-tailed gull (Larus crassirostris) eggs from Korea.

This study monitored the spatiotemporal trends of persistent organic pollutants (POPs) contamination along the Korean coasts using eggs of the black-tailed gull, a resident bird that occupies a high trophic position in the marine food web. Black-tailed gull eggs were collected from three breeding islands located in the western (Seoman-do), southern (Hong-do), and eastern (Dok-do) seas of Korea during 2015-2019, and egg contents were analyzed for classical and emerging POPs. Among the target analytes, levels of emerging POPs such as brominated flame retardants (BFRs) and perfluoroalkyl acids (PFAAs) were significantly higher in eggs from Seoman-do than other islands.

Underwater hidden microplastic hotspots: Historical ocean dumping sites.

Three ocean dumping sites located in the Yellow Sea (YS) and East Sea (ES) of South Korea have accumulated terrestrial waste from 1988 to 2015. Most of this waste comprised industrial wastewater and sewage sludge, which are sources of microplastics. In this study, we investigated the spatiotemporal distribution and characteristics of microplastics in surface and core sediments of the YS, South Sea (SS) and ES, including at dumping sites (YDP and EDP).

What type of plastic do sea turtles in Korean waters mainly ingest? Quantity, shape, color, size, polymer composition, and original usage.

Globally, sea turtles are at high risk of ingesting plastic. However, research on plastic ingestion by sea turtles in East Asia is scant, and no quantitative or qualitative investigation has been conducted in Korean waters. This study examined the plastic ingestion of sea turtles stranded, floating, or incidentally captured in Korean waters between 2012 and 2018.

A comparison of spectroscopic analysis methods for microplastics: Manual, semi-automated, and automated Fourier transform infrared and Raman techniques.

This study was conducted to establish the best practice for microplastic analysis by reducing the time demand and human bias and comparing the characteristics of μ-FTIR and Raman techniques. A manual analysis, semi-automated method, and fully automatic identification method were compared. Fully automated identification took the shortest time to analyze a whole filter paper (Ø25 mm), but its false positive identification rate was 80 ± 15%.

Levels and profiles of perfluorinated alkyl acids in liver tissues of birds with different habitat types and trophic levels from an urbanized coastal region of South Korea.

Contamination status and characteristics of perfluorinated alkyl acids (PFAAs) including perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonic acids (PFSAs) was examined using liver tissue of birds - black-tailed gulls (Larus crassirostris), domestic pigeons (Columba livia var. domestica), pacific loons (Gavia pacifica), herons (Ardea cinerea), and egrets (Egretta garzetta and Ardea alba) - with different trophic levels, habitat types and migratory behaviors from an industrialized coastal region of South Korea. A wide range of PFAAs (1.

Prevalence of small high-density microplastics in the continental shelf and deep sea waters of East Asia.

Microplastics are widely distributed throughout aquatic environments. Information about the vertical distribution and fate of microplastics in seawater remains limited. To elucidate the vertical distribution of microplastics, three to six vertical water column layers were sampled based on the thermocline depth, from which the vertical distribution and characteristics of microplastics larger than 20 μm were investigated in continental shelf and deep-sea waters around South Korea.

Ecological risk assessment of microplastics in coastal, shelf, and deep sea waters with a consideration of environmentally relevant size and shape.

This study assessed the ecological risk posed by microplastics in surface and subsurface seawaters in coastal, continental shelf, and deep-sea areas of South Korea. The target microplastics for risk assessment were specified as only non-spherical type microplastics in the size range 20-300 μm, because this type was predominantly observed in our study areas, and adverse biological effects have previously been reported. Exposure data for non-spherical microplastics were obtained from a previous study or were measured for microplastics of sizes down to 20 μm.

Relative importance of aqueous leachate versus particle ingestion as uptake routes for microplastic additives (hexabromocyclododecane) to mussels.

Microplastic pollution is emerging as a global environmental issue, and its potential for transferring hazardous chemicals to aquatic organisms is gaining attention. Studies have investigated the transfer of chemicals, mainly sorbed chemicals, through ingestion of microplastics by organisms, but limited information is available regarding chemical additives and uptake via the aqueous route through plastic leaching. In this study, we compared two bioaccumulation pathways of the additive hexabromocyclododecane (HBCD) by exposing mussels (Mytilus galloprovincialis) to two different sizes of expanded polystyrene (EPS): inedible size (4.