Assessment of anthropogenic particles in Holothuria sanctori from Tenerife (Canary Islands, Spain)

Sea cucumbers play a key role in maintaining the health of coastal marine ecosystems. The aim of this research was to evaluate the presence of anthropogenic particles in sea cucumbers of the species Holothuria sanctori in intertidal pools from Tenerife (Canary Islands, Spain) and in the surrounding seawater. In the case of sea cucumbers (n = 18), the gastrointestinal tract (particles ingested directly from the sediment) and Cuvierian tubules (particles presence as a result of gas exchange with seawater) were analysed separately. Anthropogenic particles were found in all samples, with an average concentration of 20.0 +/- 4.4 items per litre in seawater and 11.8 +/- 3.9 items per individual in the sea cucumbers, with a higher concentration of particles in the gastrointestinal tract (9.3 +/- 3.4 items per gastrointestinal tract) than in the Cuvierian tubules (2.6 +/- 3.3 items per Cuvierian tubules). Transparent and blue microfibres were predominant, accounting for over 90 % of the samples analysed. A significant proportion of these fibres were of cellulosic origin (either natural or semisynthetic, comprising 78.7 %), while fully synthetic polymers (microplastics), were also identified, including polyester and polyvinyl chloride (the latter exclusively detected in seawater).