Characteristics of microplastics in shoreline sediments from a tropical and urbanized beach (Da Nang, Vietnam)

Microplastics in shoreline sediments were investigated from Da Nang beach for the first time. Sediment samples at the two depth strata (0-5 cm and 5-10 cm) at eight sites along the entire coast were collected for identifying the characteristics of microplastics, including their concentration, size, shape, color, and nature. The synthetic fiber was the predominant type of microplastics, accounting for 99.2% of the total items. Blue (59.9%) and white (22.9%) were the most common colors of the fibers. Synthetic fibers showed a homogenous distribution at all sampling sites with a mean concentration of 9238 +/- 2097 items kg(-1) d.w. Meanwhile, the fibers tended to concentrate much more at the surface stratum than the deeper stratum. A large number of synthetic fibers (81.9%) were in the size range of 300-2600 mu m, which might pose a threat to marine biota and human health.