Effect of lithological properties of beach sediments on plastic pollution in Bodrum Peninsula (SW Türkiye).

The effects grain size on transport and retention of plastics in sediments are controversial issue. Four beaches were selected on the Bodrum Peninsula (SW Türkiye) for this study. Twenty-four samples with poorly to well sorted, sandy gravel, gravel, or gravelly sand were collected from the top five cm of the sampling quadrant's four corners and center of 1 m2 area, from shoreline and backshore. The highest plastic content (38 mesoplastics/600 g - 455 microplastics (MPs)/1200 g) was determined on the Bodrum Coast having the highest population. Polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), polyethylene terephthalate (PET) and polyurethane (PU) were predominantly detected with Fourier Transform Infrared Spectroscopy (FTIR) analysis as MPs as a fragment and fiber. This study indicates the negative correlation between grain size and the number of MPs in coastal sediments. Anthropogenic activities are evaluated as a possible primary source of plastic pollution in the study area.

Masud A ，Gül M ，Küçükuysal C ，Buluş E ，Şahin YM ... -  《-》

Abundance and distribution of microplastics on sandy beaches of the eastern Moroccan Mediterranean coast.

Microplastics (MPs) were investigated at 19 sandy beaches along the eastern Mediterranean Moroccan coast. Sediment samples (5 mm-63 μm) were analyzed to identify MPs abundance, size, shape, color and nature. MPs concentration ranged from 40 ± 7.4 to 230 ± 48.6 MPs kg-1; fibrous MPs were the most abundant (74.72 %), followed by fragments (20.26 %), films (3.27 %), pellets (1.42 %) and foams (0.33 %). Large MPs (1-5 mm) accounted for 58 %, while small (< 1 mm) for 42 %. The 1-2 mm fraction of sediments presented the greatest amounts (30.67 %) of MPs. Transparent (50 %) and blue (17 %) were most common colors and most of particles were angular and irregularly shaped. Fourier Transform Infrared Spectroscopy (FTIR) analysis showed that PE (Polyethylene), PS (Polystyrene) and PP (Polypropylene) and PVC (Polyvinyl chloride) were the most common polymers. These findings revealed a moderate level of microplastic pollution along the beaches of the eastern Moroccan Mediterranean coast.

Azaaouaj S ，Nachite D ，Anfuso G ，Er-Ramy N ... -  《-》

Evidence of microplastics pollution in coastal beaches and waters in southern Sri Lanka.

The abundance of microplastics (MPs) in surface water and beach sediment in Southern Sri Lanka covering a distance of 91 km of coastline is reported. MPs were classified according to polymer type, geometry and color of the sites tested 60% showed MP contamination in sand and 70% in surface waters off the coast. The size range of MPs from surface waters and beaches were to 1.5-2.5 mm and 3-4.5 mm, respectively. Majority of these were identified as polyethylene (PE) and polypropylene (PP) with some polystyrene (PS) foam at a few sites. Fragments derived from larger debris appears to be the dominant type of MP at most sites and only 2 sites showed virgin pellets that accounted for 14% of the samples collected.

Bimali Koongolla J ，Andrady AL ，Terney Pradeep Kumara PB ，Gangabadage CS ... -  《-》

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 ... -  《-》

Abundance, characteristics and surface degradation features of microplastics in beach sediments of five coastal areas in Tamil Nadu, India.

This study undertook to investigate the occurrence of microplastics (MPs) in the high and low-tide sediments of five coastal areas in Tamil Nadu, India. The abundance of microplastics vary from 439 ± 172 to 119 ± 72 (HTL) and 179 ± 68 to 33 ± 30 (LTL) items kg-1 of sediments. The MP polymers found in the study sites are Polyethylene (73.2%), polypropylene (13.8%), nylon (8.2%), polystyrene (2.8%) and polyester (2%). The weathered surfaces might act as high-capacity carriers and this was confirmed by SEM-EDAX. The results of an analysis of the textures of the sediments do not ascribe any influence on microplastic abundance. The recreation, religious and fishing activities are the major contributors to plastic pollution in these beaches, which is borne out by the high abundance of MPs in the study sites. A regular and permanent waste management system should be put in place for the protection of beaches.

Sathish N ，Jeyasanta KI ，Patterson J 《-》