Table_1_Microplastics pollution in genetically connected populations of Holothuria forskali from south Bay of Biscay.xlsx

IntroductioSea cucumbers are increasingly demanded as seafood in different cultures around the world. Holothurians could be potentially exploited in southern Bay of Biscay (Iberian Cantabrian coast) where they are not fished yet. Recent studies show relatively high pollution by emerging pollutants like microplastics (MPs) in the region; perhaps the exposure of holothurians to those MPs may put them at risk.Material and methodsHere we analysed 60 samples of Holothuria forskali taken from the west and east of the Cape Peñas transition zone in different seasons. MPs were quantified from body wall tissue, and mitochondrial DNA sequences (16S and COI genes) were employed to determine population connectivity and infer replenishment capacity.ResultsMuch higher MPs content in holothurian tissue than in water and sediments confirmed bioconcentration in this species. Significant differences between sampling locations were found, holothurian pollution being consistent with the occurrence of MPs sources like rivers, fishing ports and aquaculture. Genetic connectivity and no signals of diversity reduction in the most polluted samples suggest population replenishment capacity in H. forskali in the studied region. Results for a few samples of H. mammata from the same sampling points confirmed a higher MPs pollution at the west of Cape Peñas.DiscussionAccording to these exploratory results, sea cucumbers seem to accumulate MPs especially in the western Cantabrian Sea. Further studies are recommended to understand the possible MPs threat for these holothurian species.

海参在全球各文化中的海鲜需求日益增长。在尚未进行捕捞的比斯开湾南部（伊比利亚坎塔布连海岸），海参的潜在开发或许可行。近期研究表明，该地区新兴污染物如微塑料（MPs）的污染程度相对较高；或许海参对这些MPs的暴露可能使其处于风险之中。在材料与方法部分，本研究分析了来自佩尼亚斯角过渡区东西两侧60个样品的Holothuria forskali，并在不同的季节进行采样。通过体壁组织量化MPs，并采用线粒体DNA序列（16S和COI基因）来确定种群连通性并推断补充能力。结果表明，海参组织中的MPs含量远高于水和沉积物，证实了该物种的生物富集现象。采样地点之间存在显著差异，海参污染与MPs来源如河流、渔港和养殖业的分布一致。遗传连通性以及在最污染样品中未发现多样性降低的信号，表明研究区域内的H. forskali种群具有补充能力。来自同一采样点的少量H. mammata样品的结果证实了佩尼亚斯角西侧的MPs污染程度较高。在讨论部分，根据这些探索性结果，海参似乎在坎塔布连海的西部地区特别积累MPs。建议进行进一步研究，以了解这些海参物种可能面临的MPs威胁。