Though plastics show good chemical inertness, they could sorb polychlorinated biphenyls (PCBs) and other toxic pollutants from the surrounding environment. Thus, ingestion of microplastics by marine organisms potentially enhances the transport and bioavailability of toxic chemicals. However, there is lack of studies on the sorption capacity, mechanism and factors affecting the sorption behavior. Here, sorption of PCBs by microplastics in the simulated seawater was studied using the batch oscillation equilibration technique, in which polypropylene (PP) and 3,3',4,4'-tetrachlorobiphenyl (PCB77) acted as model plastic and PCB, respectively. Factors including particle size, temperature and solution environment were investigated. Results showed that, equilibrium sorption time is about 8h and sorption capacity increase with decreasing particle size and temperature. Different sorption capacity in three solution environments was observed. Equilibrium data in three solution environments fitted very well to the Langmuir sorption model, indicating chemical sorption is the predominant mechanism.

中文翻译：

---

微塑料对3,3'，4,4'-四氯联苯的吸附：以聚丙烯为例。

尽管塑料表现出良好的化学惰性，但它们可以吸收周围环境中的多氯联苯（PCB）和其他有毒污染物。因此，海洋生物摄入微塑料可能会增强有毒化学物质的运输和生物利用度。然而，关于吸附能力，影响吸附行为的机理和因素尚缺乏研究。在此，采用间歇振荡平衡技术研究了微塑料在模拟海水中对PCBs的吸附，其中聚丙烯（PP）和3,3'，4,4'-四氯联苯（PCB77）分别用作模型塑料和PCB。研究了粒径，温度和溶液环境等因素。结果表明，平衡吸附时间约为8h，吸附能力随粒径和温度的降低而增加。在三种溶液环境中观察到不同的吸附容量。三种溶液环境中的平衡数据非常适合Langmuir吸附模型，表明化学吸附是主要机理。