College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China.
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, China; Key Laboratory of Plant Nutrition and the Agro-environment in Northwest China, Ministry of Agriculture, Yangling, Shaanxi, 712100, China.
Ecotoxicol Environ Saf. 2021 Jan 1;207:111255. doi: 10.1016/j.ecoenv.2020.111255. Epub 2020 Sep 6.
Microplastics are widespread in the environment and might transport readily by ocean currents, wind and atmospheric deposition. Simultaneously, antibiotics and heavy metals could often be detected in the environment. They are both positively charged, it is necessary to clarify the interactions of these pollutants with microplastics when they were coexist. In this study, the most commonly used polystyrene (PS) was selected as a representative microplastic. This study investigated the effect of Cd(II) on the sorption of TYL by PS in different coexistence systems. The results showed that: in the composite system, when TYL and Cd(II) coexist, the presence of Cd(II) could inhibit the sorption of TYL by PS, and the inhibitory effect increases with the increase of the concentration of Cd(II), indicating that competitive sorption dominates the sorption. When PS adsorbed Cd(II) first and then adsorbed TYL, the presence of Cd(II) was conducive to the sorption of TYL, and the sorption strengthened with the increase of Cd(II) concentration, indicating that the complexation between TYL and Cd(II) enhanced the sorption of TYL. In addition, initial pH values and ionic strength were essential in the sorption process. Therefore, this study could provide an important basis for evaluating the environmental behavior and ecological risk of microplastics in the process of compound pollution.
微塑料广泛存在于环境中，容易通过洋流、风和大气沉降进行迁移。同时，抗生素和重金属经常在环境中被检测到。它们都带正电荷，因此有必要澄清当这些污染物共存时，它们与微塑料的相互作用。在这项研究中，选择最常用的聚苯乙烯（PS）作为代表性的微塑料。本研究调查了 Cd(II) 在不同共存体系中对 PS 吸附 TYL 的影响。结果表明：在复合体系中，当 TYL 和 Cd(II)共存时，Cd(II)的存在会抑制 PS 对 TYL 的吸附，抑制作用随 Cd(II)浓度的增加而增加，表明竞争吸附占主导地位。当 PS 先吸附 Cd(II)然后再吸附 TYL 时，Cd(II)的存在有利于 TYL 的吸附，且随着 Cd(II)浓度的增加，吸附作用增强，表明 TYL 和 Cd(II)之间的络合增强了 TYL 的吸附。此外，初始 pH 值和离子强度是吸附过程中的重要因素。因此，本研究可为评估微塑料在复合污染过程中的环境行为和生态风险提供重要依据。
