School of Materials and Chemical Engineering, Xi'an Technological University, 4 Jinhua Road, Xi'an, 710021, China; State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
Chemosphere. 2021 Jan;263:128001. doi: 10.1016/j.chemosphere.2020.128001. Epub 2020 Aug 16.
Influences of colloidal stabilities of nanoparticles (NPs) on the bioaccumulation of co-existing pollutants remains largely unknown. In this study, two oxidation products of nanoscale zero-valent iron (nZVI) with totally varied colloidal stabilities, termed highly oxidized nZVI (HO-nZVI) and lowly oxidized nZVI (LO-nZVI), were exposed to zebrafish with chromium (Cr); this approach was used to investigate the impacts of colloidal stability of oxidized nZVI on the bioaccumulation of Cr in zebrafish. A significant increase in the Cr and NP content in the viscera of fish in the presence of the oxidized nZVI after 20 days of exposure was confirmed, which indicated that Cr was consumed by fish through the uptake of the NPs. Furthermore, a significantly higher level of the HO-nZVI accumulated in the viscera in contrast to LO-nZVI, which suggested that the colloidal stability of NP is a crucial factor when evaluating the accessibility of NPs to zebrafish. Thus, HO-nZVI induced a significantly stronger enhancement of Cr content in fish than LO-nZVI. Our results suggest that oxidized nZVI will act as the carrier of co-existing heavy metals and change the transportation and distribution of heavy metals in zebrafish; moreover, the colloidal stability of NP will have a significant influence on the bioaccumulation of coexisting Cr.
纳米颗粒 (NPs) 的胶体稳定性对共存污染物的生物累积的影响在很大程度上尚不清楚。在这项研究中，两种纳米零价铁 (nZVI) 的氧化产物具有完全不同的胶体稳定性，分别称为高度氧化的 nZVI (HO-nZVI) 和低度氧化的 nZVI (LO-nZVI)，被暴露于同时含有铬 (Cr) 的斑马鱼中；这种方法用于研究氧化 nZVI 的胶体稳定性对斑马鱼中 Cr 生物累积的影响。在暴露 20 天后，在存在氧化 nZVI 的情况下，鱼内脏中的 Cr 和 NP 含量显著增加，这表明 Cr 是通过鱼对 NPs 的摄取被消耗的。此外，与 LO-nZVI 相比，HO-nZVI 在鱼内脏中的积累水平显著更高，这表明 NP 的胶体稳定性是评估 NPs 对斑马鱼的可及性的关键因素。因此，HO-nZVI 诱导的鱼体内 Cr 含量的增强明显强于 LO-nZVI。我们的研究结果表明，氧化 nZVI 将作为共存重金属的载体，改变重金属在斑马鱼体内的运输和分布；此外，NP 的胶体稳定性将对共存 Cr 的生物累积产生重大影响。
