Department of Environmental Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea.
Department of Bioengineering, Division of Chemical Engineering and Bioengineering, College of Art, Culture and Engineering, Kangwon National University, Chuncheon 24341, Republic of Korea; Department of Smart Health Science and Technology, Kangwon National University, Chuncheon 24341, Republic of Korea.
Sci Total Environ. 2023 Jul 1;880:163290. doi: 10.1016/j.scitotenv.2023.163290. Epub 2023 Apr 6.
Microplastics (MP) have been recently identified as emerging water contaminants in worldwide. Owing to its physicochemical properties, MP have been considered as a vector of other micropollutants and may affect their fate and ecological toxicity in the water environment. In this study, triclosan (TCS), which is a widely-used bactericide, and three frequently found types of MP (PS-MP, PE-MP, and PP-MP) were investigated. The adsorption behavior of TCS on MP was investigated by the effect of reaction time, initial concentration of TCS, and other water chemistry factors. Elovich model and Temkin model are the most fitted well with kinetics and adsorption isotherms, respectively. The maximum TCS adsorption capacities were calculated for PS-MP (9.36 mg/g), PP-MP (8.23 mg/g), and PE-MP (6.47 mg/g). PS-MP had higher affinity to TCS owing to hydrophobic and π-π interaction. The TCS adsorption on PS-MP was inhibited by decreasing concentrations of cations, and increasing concentration of anion, pH, and NOM concentration. At pH 10, only 0.22 mg/g of adsorption capacity was obtained because of the isoelectric point (3.75) of PS-MP and pKa (7.9) of TCS. And almost no TCS adsorption occurred at NOM concentration of 11.8 mg/L. Only PS-MP had no acute toxic effect on D. magna, whereas TCS showed acute toxicity (EC of TCS = 0.36 ± 0.4 mg/L). Although survival rate increased when TCS with PS-MP due to lower the TCS concentration in solution via adsorption, PS-MP was observed in intestine and body surface of D. magna. Our findings can contribute to understanding the combined potential effects of MP fragment and TCS to aquatic biota.
微塑料（MP）最近被确定为全球范围内新出现的水污染物。由于其物理化学性质，MP 被认为是其他微量污染物的载体，并可能影响它们在水环境中的命运和生态毒性。在本研究中，三氯生（TCS），一种广泛使用的杀菌剂，和三种常见的 MP（PS-MP、PE-MP 和 PP-MP）被研究。通过反应时间、TCS 的初始浓度和其他水化学因素的影响，研究了 TCS 在 MP 上的吸附行为。Elovich 模型和 Temkin 模型分别与动力学和吸附等温线拟合最好。PS-MP（9.36mg/g）、PP-MP（8.23mg/g）和 PE-MP（6.47mg/g）的最大 TCS 吸附容量被计算出来。PS-MP 对 TCS 具有更高的亲和力，这是由于疏水和π-π相互作用。TCS 在 PS-MP 上的吸附受到阳离子浓度降低、阴离子浓度增加、pH 值和 NOM 浓度增加的抑制。在 pH 为 10 时，由于 PS-MP 的等电点（3.75）和 TCS 的 pKa（7.9），只有 0.22mg/g 的吸附容量，几乎没有 TCS 吸附发生在 NOM 浓度为 11.8mg/L。只有 PS-MP 对 D. magna 没有急性毒性作用，而 TCS 表现出急性毒性（TCS 的 EC = 0.36±0.4mg/L）。尽管由于吸附作用降低了溶液中 TCS 的浓度，当 TCS 与 PS-MP 一起存在时，D. magna 的存活率增加，但仍在 D. magna 的肠道和体表观察到 PS-MP。我们的研究结果有助于理解 MP 碎片和 TCS 对水生生物群的联合潜在影响。
