Department of Environmental Health Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea.
Department of Environmental Health Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Korea.
Aquat Toxicol. 2021 Nov;240:105968. doi: 10.1016/j.aquatox.2021.105968. Epub 2021 Sep 14.
Microfibers, which are sourced from textiles and some products from the fishery industry, are the biggest contributors to microplastic pollution in aquatic ecosystems. In addition to these synthetic microfibers, naturally derived microfibers can also be found in aquatic environments. However, there are limited studies on the ecotoxicity of natural microfibers. To shed light on this topic, this study assessed and compared the toxicity of natural and synthetic microfibers on Daphnia magna, using lyocell, polyester (PET) and polypropylene (PP) microfibers. To evaluate the adverse effect of microfibers on D. magna, after effects including depuration, food intake, growth, mortality, and immobilization rate were continually observed for up to 96 h after the initial 48 h of exposure to the microfibers. Immobilization rate decreased in the following order: PP, PET, and lyocell. However, the depuration of microfibers in the lyocell and PET treatment groups was similar, with higher mortality rates than in the PP treatment group. Furthermore, despite the high rates of food intake following exposure, the lyocell and PET exposed groups exhibited growth inhibition during the same period. This growth inhibition corresponded with, and was likely due to, reductions in the length of gut microvilli, probably an expression of gut damage, which is believed to have reduced nutrient absorption in the affected individuals. Based on the results of this study, it was confirmed that even natural microfibers, and not just synthetic microfibers, can have adverse effects on aquatic organisms. This study confirmed not only the toxicity of microfibers, but also the consequences of their after effects. These results could be the basis for future research on the after effects of microplastics on aquatic organisms and provide directions for further microplastic ecotoxicity studies.
微纤维主要来源于纺织品和一些渔业产品，是水生生态系统中微塑料污染的最大贡献者。除了这些合成微纤维外，水生环境中也可以发现天然衍生的微纤维。然而，关于天然微纤维的生态毒性研究有限。为了阐明这一主题，本研究使用粘胶纤维、聚酯（PET）和聚丙烯（PP）微纤维评估和比较了天然和合成微纤维对大型溞的毒性。为了评估微纤维对大型溞的不良影响，在暴露于微纤维的最初 48 小时后，连续观察长达 96 小时，评估了微纤维对大型溞的后续影响，包括净化、摄食、生长、死亡率和固定率。固定率的降低顺序为：PP、PET 和粘胶纤维。然而，粘胶纤维和 PET 处理组中微纤维的净化情况相似，死亡率高于 PP 处理组。此外，尽管暴露后食物摄入量较高，但在同一时期，暴露于粘胶纤维和 PET 的组表现出生长抑制。这种生长抑制与肠道微绒毛长度的减少相对应，可能是肠道损伤的表现，这可能导致受影响个体的营养吸收减少。基于本研究的结果，证实了即使是天然微纤维，而不仅仅是合成微纤维，也会对水生生物产生不良影响。本研究不仅证实了微纤维的毒性，还证实了其后续影响的后果。这些结果可能为未来研究微塑料对水生生物的后续影响提供基础，并为进一步的微塑料生态毒性研究提供方向。
