Abundance and distribution of large microplastics (1-5 mm) within beach sediments at the Po River Delta, northeast Italy.

Coastal areas are especially prone to plastic debris, being subjected to various land- and sea-based sources. Nevertheless, knowledge about microplastic distribution on beaches is limited, as studies focused either on high tide lines, specific items, or relied on visual identification. Beaches exhibit several accumulation zones and microplastic deposition depends on particle properties. We thus studied microplastic distribution (1-5 mm), including various types and shapes, among three driftlines at three beaches within the Po River Delta. Particles were analyzed using ATR-FTIR spectroscopy. Abundances ranged from 2.92 (± 4.86 SD) to 23.30 (± 45.43 SD) microplastics per kilogram dry weight between the beaches. The accumulation of microplastics among driftlines showed no consistent pattern, besides expanded polystyrene tending to accumulate backshore. We observed that accumulation hotspots within a single driftline can disrupt a general observed accumulation pattern. Thus, microplastic monitoring guidelines should further include protocols for the handling of accumulation hotspots within datasets.

Piehl S ，Mitterwallner V ，Atwood EC ，Bochow M ，Laforsch C ... -  《-》

Occurrence and identification of microplastics along a beach in the Biosphere Reserve of Lanzarote.

This work studied the accumulation of plastic debris in a remote beach located in La Graciosa island (Chinijo archipelago, Canary Islands). Microplastics were sampled in the 1-5 mm mesh opening range. An average plastic density of 36.3 g/m2 was obtained with a large variability along the 90 m of the beach (from 8.5 g/m2 to 103.4 g/m2). Microplastic particles preferentially accumulated in the part of the beach protected by rocks. A total number of 9149 plastic particles were collected, recorded and measured, 87% of which corresponded to fragments. Clear colours and microscopic evidence of weathering corresponded to aged plastics wind-driven by the surface Canary Current. The chemical composition of plastics particles corresponded to PE (63%), PP (32%) and PS (3%). Higher PE/PP ratios were recorded in the more protected parts of the beach, suggesting preferential accumulation of more aged fragments.

Edo C ，Tamayo-Belda M ，Martínez-Campos S ，Martín-Betancor K ，González-Pleiter M ，Pulido-Reyes G ，García-Ruiz C ，Zapata F ，Leganés F ，Fernández-Piñas F ，Rosal R ... -  《-》

Evaluation of microplastics in beach sediments along the coast of Dubai, UAE.

Microplastic contamination in beach sediments along coast of Dubai is un-documented. In this study, microplastic contamination in beach sediments collected from the wrack lines of 16 beaches in Dubai was evaluated. Five samples were collected from each beach along a 100 m stretch using a 0.5 m by 0.5 m, quadrant. The number, color, and shape of microplastics were documented. The polymer types of large fibers and strings were identified through FT-IR analysis. 480 microplastics from each of the 16 beaches were selected to detect heavy metals using XRF analysis. The results showed that the average weight of microplastic is 0.33 mg per gram of dry sediment (or 953 mg·m-2) and the number of microplastic is 59.71 items per kg of dry sediment (or 165 items·m-2). Blue and fibrous microplastics were dominant. Polyethylene strings and fibers were abundantly found. 13 heavy metals were identified of which five are priority pollutants.

Aslam H ，Ali T ，Mortula MM ，Attaelmanan AG ... -  《-》

Abundance, composition, and distribution of microplastics larger than 20 μm in sand beaches of South Korea.

To support microplastic management, the abundance, composition, and spatial distribution of microplastics on a national scale must be known. Hence, we studied the baseline level of microplastic pollution at 20 sandy beaches along the South Korean coast. All microplastic particles extracted from the sand samples were identified down to 20 μm in size using Fourier transform infrared spectroscopy. The abundances of large microplastics (L-MPs; 1-5 mm) and small microplastics (S-MPs; 0.02-1 mm) were in the range of 0-2088 n/m2 and 1400-62800 n/m2, respectively. Maximum microplastic abundance was in the size range of 100-150 μm, and particles smaller than 300 μm accounted for 81% of the total abundance. Expanded polystyrene (EPS) accounted for 95% of L-MPs, whereas S-MPs were predominantly composed of polyethylene (49%) and polypropylene (38%). The spatial distribution of L-MPs, excluding EPS, was significantly related to population, precipitation, proximity to a river mouth and abundance of macroplastic debris on beach. However, there were no relationships between S-MPs and other environmental and source-related factors, except for macroplastic debris and L-MPs excluding EPS. These results imply that S-MPs are mainly produced on beaches by weathering, whereas L-MPs other than EPS are mainly introduced from land-based sources and are also partly produced on beaches.

Eo S ，Hong SH ，Song YK ，Lee J ，Lee J ，Shim WJ ... -  《-》

Characterization, source, and retention of microplastic in sandy beaches and mangrove wetlands of the Qinzhou Bay, China.

Severe microplastic pollution from anthropogenic activities in coastal zones presents an imminent risk to marine ecosystems. In this study, abundant microplastics (15-12,852 items kg-1) with sizes ranging between 0.16 and 5.0 mm were extracted from 17 sediment samples collected in sandy beaches and mangrove wetlands of the Qinzhou Bay, Guangxi Province, Southwest China. Three types of microplastics (i.e. polystyrene, polypropylene, and polyethylene) were identified with Fourier transform infrared (FTIR) spectroscopy analysis. These detected microplastics were characterized by different colors (white, transparent, yellow, green, red, and blue) and shapes (fragment, fiber, and sphere). Microplastics were concentrated on supratidal beaches and wetlands outside of mangrove, and less abundant on intertidal beaches and inside of mangrove wetlands. Meanwhile, high microplastic concentrations were observed near mollusk farms. The spatial distribution and chemical speciation indicated that microplastics were derived from disintegration of large plastic debris (e.g., Styrofoam buoys used to support mollusk rafts) abandoned by aquaculture industry. Further, coastal vegetation (e.g. mangrove) could trap microplastic particles.

Li J ，Zhang H ，Zhang K ，Yang R ，Li R ，Li Y ... -  《-》