Departamento de Química, Unidad Departamental de Química Analítica, Facultad de Ciencias, Universidad de La Laguna (ULL), Avda. Astrofísico Fco. Sánchez, s/n, 38206, San Cristóbal de La Laguna, Spain.
Departamento de Biología Animal, Edafología y Geología, Facultad de Ciencias, Universidad de La Laguna (ULL), Avda. Astrofísico Fco. Sánchez, s/n, 38206, San Cristóbal de La Laguna, Spain.
Chemosphere. 2022 Feb;288(Pt 2):132530. doi: 10.1016/j.chemosphere.2021.132530. Epub 2021 Oct 12.
In this work, the microplastic content of sediments collected in July 2020 between 5 and 7 m depth was studied in four locations of La Palma island (Canary Islands, Spain). At each sampling location, three samples were taken parallel to the shoreline. The microplastic content in each sampling corer was studied every 2.5 cm depth after digestion with a HO solution followed by flotation in a saturated NaCl solution. Visualization of the final filtrates under a stereomicroscope revealed that all the sediment samples evaluated contained mostly microfibers (98.3%) which were mainly white/colorless (86.0%) and blue (9.8%), with an average length of 2423 ± 2235 (SD) mm and an average concentration of 2682 ± 827 items per kg of dry weight, being the total number of items found 1,019. Fourier Transform Infrared microscopy analysis of 13.9% (n = 139) of the microfibers also showed that they were mainly cellulosic (81.3%). No significant differences were found between the depths of the sediment. However, significant differences were found between the number of fibers from the sampling sites at the east and west of the island. Such variability could be driven by the winds and ocean mesoscale dynamics in the area. This study confirms the wide distribution of microfibers in sediments from an oceanic island like La Palma, providing their first report in marine sediments of the Canary Islands.
本工作研究了 2020 年 7 月在西班牙加那利群岛拉帕尔马岛 5 至 7 米深度的四个地点采集的沉积物中的微塑料含量。在每个采样点，从岸线平行采集了三个样本。在用 HO 溶液消解后，对每个采样芯的微塑料含量进行了研究，然后在饱和 NaCl 溶液中进行浮选。在立体显微镜下观察最终滤出物，发现所有评估的沉积物样品主要含有微纤维（98.3%），主要为白色/无色（86.0%）和蓝色（9.8%），平均长度为 2423 ± 2235（SD）mm，平均浓度为 2682 ± 827 个/千克干重，发现的总微纤维数量为 1019 个。对 13.9%（n = 139）的微纤维进行傅里叶变换红外显微镜分析还表明，它们主要为纤维素（81.3%）。沉积物的深度之间没有发现显著差异。然而，在岛的东西两侧采样点的纤维数量之间发现了显著差异。这种可变性可能是由该地区的风和海洋中尺度动力引起的。本研究证实了微纤维在拉帕尔马等海洋岛屿沉积物中的广泛分布，这是加那利群岛海洋沉积物中首次报道。
