Microplastic abundance in sea cucumber at seagrass ecosystem of Bintan Island and surrounding area, Indonesia

Abstract The increasing use of plastic in various aspects of life impacts the increase in plastic waste in the environment. The plastics are degraded into the smallest fragments to a size of <5 mm called microplastics. Further, microplastics will accumulate in the water, marine biota, and sediment. Sea cucumbers are deposited feeder and found in the seagrass ecosystem. This study aims to examine the abundance of microplastics in sea cucumbers, which are scattered in seagrass ecosystems in the waters of Bintan Island and the surrounding area. The method used is a purposive random sampling in a seagrass ecosystem area of 100 × 20 meters. The sea cucumbers obtained will then be dissected and observed for their microplastic content. The results showed that the sea cucumber found in the seagrass ecosystem on the Bintan island are Holothuria atra, H. scabra , and Sticopus variegatus . The highest density of sea cucumbers was found in Pengujan waters, with a value of 90 ind/ha. The highest microplastic content in sea cucumbers was found in Pengudang water, with a total of 52 ± 7.68 particles/ind. The dominant type of microplastics is fiber, with a total of 84 particles/ind.