School of Environment, Tsinghua University, Beijing, 100084, China.
School of Environment, Tsinghua University, Beijing, 100084, China.
Chemosphere. 2019 Sep;231:308-314. doi: 10.1016/j.chemosphere.2019.05.116. Epub 2019 May 18.
PS microplastic particle (<5 mm) is an emerging contaminant of concern in aquatic and sediment systems with reported negative impacts on environmental and human health. TCS is a broad-spectrum antimicrobial which can affect ecosystems and result in long-term human health risks. The interaction between TCS and PS microplastic, partly determines the behavior and dispersion of TCS in the environment. In this study, the sorption kinetics and isotherms for TCS and PS microplastic were investigated. The influences of temperature, pH, ionic strength and coexisting heavy metals were assessed in batch experiments. The pseudo-second-order model (PSOM) was found to effectively describe the sorption kinetics of TCS on PS. TCS sorption on PS was found to be higher within the pH range of 3.0-6.0, while a decrease occurred at pH > 6.0. This result indicates that TCS was the major species contributing to the sorption process through hydrophobic interaction. Temperature did not affect the sorption of TCS on polystyrene, with sorption K values of 0.15, 0.16, 0.18 and 0.17 L/g at 288, 298, 308 and 318 K, respectively. Furthermore, the sorption amount of TCS showed no obvious variation with NaCl concentrations varying between 0.001 and 0.1 M. Finally, the coexistence of Cu(II)/Zn(II) had no significant influence on TCS sorption on PS, as Cu(II)/Zn(II) and TCS had different mechanisms of sorption on PS.
PS 微塑料颗粒（<5 毫米）是水生和沉积物系统中一种新兴的关注污染物，据报道对环境和人类健康有负面影响。TCS 是一种广谱抗菌剂，会影响生态系统，并导致长期的人类健康风险。TCS 和 PS 微塑料之间的相互作用部分决定了 TCS 在环境中的行为和分散。在这项研究中，研究了 TCS 和 PS 微塑料的吸附动力学和等温线。在批处理实验中评估了温度、pH 值、离子强度和共存重金属的影响。发现拟二级模型（PSOM）有效地描述了 TCS 在 PS 上的吸附动力学。TCS 在 PS 上的吸附在 pH 值为 3.0-6.0 的范围内较高，而在 pH 值>6.0 时则降低。这一结果表明，TCS 是通过疏水相互作用主导吸附过程的主要物质。温度不影响 TCS 在聚苯乙烯上的吸附，在 288、298、308 和 318 K 时，吸附 K 值分别为 0.15、0.16、0.18 和 0.17 L/g。此外，TCS 的吸附量在 0.001 到 0.1 M 之间的 NaCl 浓度变化时没有明显变化。最后，Cu(II)/Zn(II) 的共存对 TCS 在 PS 上的吸附没有显著影响，因为 Cu(II)/Zn(II)和 TCS 在 PS 上的吸附机制不同。
