Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain.
IMIDRA, Instituto Madrileño de Investigación y Desarrollo Rural Agrario y Alimentación, Finca "El Encín", A-2, Km 38,2, 28800 Alcalá de Henares, Madrid, Spain.
Sci Total Environ. 2015 Dec 1;535:79-84. doi: 10.1016/j.scitotenv.2015.03.067. Epub 2015 Apr 8.
In the present study, the residual toxicity and impact of aged nZVI after a leaching experiment on heavy metal (Pb, Zn) polluted soils was evaluated. No negative effects on physico-chemical soil properties were observed after aged nZVI exposure. The application of nZVI to soil produced a significant increase in Fe availability. The impact on soil biodiversity was assessed by fluorescence in situ hybridization (FISH). A significant effect of nZVI application on microbial structure has been recorded in the Pb-polluted soil nZVI-treated. Soil bacteria molecular response, evaluated by RT-qPCR using exposure biomarkers (pykA, katB) showed a decrease in the cellular activity (pykA) due to enhanced intracellular oxidative stress (katB). Moreover, ecotoxicological standardised test on Caenorhabditis elegans (C. elegans) showed a decrease in the growth endpoint in the Pb-polluted soil, and particularly in the nZVI-treated. A different pattern has been observed in Zn-polluted soils: no changes in soil biodiversity, an increase in biological activity and a significant decrease of Zn toxicity on C. elegans growth were observed after aged nZVI exposure. The results reported indicated that the pollutant and its nZVI interaction should be considered to design soil nanoremediation strategies to immobilise heavy metals.
在本研究中，评估了老化纳米零价铁（nZVI）在重金属（Pb、Zn）污染土壤浸出实验后的残留毒性和影响。暴露于老化 nZVI 后，土壤理化性质没有受到负面影响。nZVI 的应用使土壤中 Fe 的有效性显著增加。通过荧光原位杂交（FISH）评估 nZVI 对土壤生物多样性的影响。在 Pb 污染土壤中，nZVI 的应用对微生物结构产生了显著影响。用暴露生物标志物（pykA、katB）进行的 RT-qPCR 评估了土壤细菌的分子反应，结果表明由于细胞内氧化应激增强（katB），细胞活性（pykA）下降。此外，用秀丽隐杆线虫（C. elegans）进行的生态毒理学标准化测试表明，在 Pb 污染土壤中，尤其是在 nZVI 处理的土壤中，生长终点下降。在 Zn 污染土壤中观察到了不同的模式：暴露于老化 nZVI 后，土壤生物多样性没有变化，生物活性增加，C. elegans 生长的 Zn 毒性显著降低。报告的结果表明，应考虑污染物及其与 nZVI 的相互作用，以设计土壤纳米修复策略来固定重金属。
