University of El Manar, Faculty of Sciences of Tunis, Department of Biology, Ecology, Biology and Physiology of Aquatic Organisms Laboratory, Tunis, Tunisia.
Group of Fundamental and Applied Malacology (MAF), Laboratory of Environment Bio-Monitoring (LBE), Faculty of Sciences of Bizerte, University of Carthage, 7021, Zarzouna, Bizerte, Tunisia.
Chemosphere. 2024 Nov;367:143588. doi: 10.1016/j.chemosphere.2024.143588. Epub 2024 Oct 30.
Pentachlorophenol (PCP) and polyethylene microplastic (PE-MP) have been designated as emerging and persistent pollutants, respectively. The combined effects of those pollutants are still unknown, especially to organisms like phytoplankton that may adsorb to their surface. Therefore, the purpose of this study was to investigate for the first time the effects of PE-MP alone and in combination with PCP on the microalgae Isochrysis galbana, clone t-ISO following 72 h of exposure. Photosynthetic pigments amounts, carotenoid, protein, carbohydrate and fatty acids have been assessed. Acute toxicity test showed that the 72 h median inhibition concentration (72 h-EC) was 148.2, 0.66 and 087 mg L for PE-MP, PCP and their mixture. The utmost effects in growth inhibition rates were noted with 0.5 and 1.25 mg L PCP (23% and 85%, respectively), and 100 and 300 mg L PE-MP (49% and 64%, respectively). Moreover, it was found that those concentrations had a major impact on the photosynthetic pigments, protein, carbohydrate, and fatty acids amounts in algal cells. Furthermore, levels of HO and Malondialdehyde (MDA), as well as the activities of catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX), indicated the induction of an oxidative stress in algal cells. It appears that adding PE-MP at a no-effect concentration (25 mg L) reduces the toxicity caused by PCP due to its adsorption to polyethylene microplastics.
五氯苯酚（PCP）和聚乙烯微塑料（PE-MP）分别被指定为新兴污染物和持久性污染物。这些污染物的联合效应尚不清楚，尤其是对于可能吸附在其表面的浮游植物等生物。因此，本研究的目的是首次研究单独和联合暴露于 PE-MP 和 PCP 对小球藻 Isochrysis galbana，克隆 t-ISO 的影响，暴露时间为 72 小时。评估了光合色素、类胡萝卜素、蛋白质、碳水化合物和脂肪酸的含量。急性毒性试验表明，PE-MP、PCP 及其混合物的 72 小时半数抑制浓度（72 h-EC）分别为 148.2、0.66 和 0.87 mg/L。在生长抑制率方面，0.5 和 1.25 mg/L 的 PCP（分别为 23%和 85%）以及 100 和 300 mg/L 的 PE-MP（分别为 49%和 64%）的抑制效果最为显著。此外，研究发现这些浓度对藻类细胞中的光合色素、蛋白质、碳水化合物和脂肪酸含量有重大影响。此外，HO 和丙二醛（MDA）水平以及过氧化氢酶（CAT）、超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）的活性表明，藻类细胞中诱导了氧化应激。似乎在无效应浓度（25 mg/L）下添加 PE-MP 可以减少 PCP 的毒性，因为它会被吸附到聚乙烯微塑料上。
