Yang Ying-Fei, Chen Pei-Jen, Liao Vivian Hsiu-Chuan
Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Roosevelt Road, Sec. 4, Taipei 106, Taiwan.
Department of Agricultural Chemistry, National Taiwan University, No. 1, Roosevelt Road, Sec. 4, Taipei 106, Taiwan.
Chemosphere. 2016 May;150:615-623. doi: 10.1016/j.chemosphere.2016.01.068. Epub 2016 Jan 28.
Nanoscale zerovalent iron (nZVI) is widely used with large scale for environmental remediation for in situ or ex situ applications. The potential impact of nZVI on biota at environmentally relevant concentrations needs to be elucidated. In this study, the reproductive toxicities of three irons species: carboxymethyl cellulose (CMC)-stabilized nZVI, nanoscale iron oxide (nFe3O4), and ferrous ion (Fe(II)aq) in the soil-dwelling nematode Caenorhabditis elegans were examined. In addition, the generational transfer of reproductive toxicity of CMC-nZVI on C. elegans was investigated. The results showed that CMC-nZVI, nFe3O4, and Fe(II)aq did not cause significant mortality after 24 h exposure at the examined concentrations. Reproductive toxicity assays revealed that CMC-nZVI, nFe3O4, and Fe(II)aq significantly decreased offsprings in parental generation (F0) in accompany with the increased intracellular reactive oxygen species (ROS). Furthermore, the reproductive toxicity of CMC-nZVI at environmentally relevant concentrations was transferrable from the F0 to the F1 and F2 generations, but then recovered in the F3 and F4 generations. Further evidence showed that total irons were accumulated in the F0 and F1 generations of C. elegans after CMC-nZVI parental exposure. This study demonstrated that environmentally relevant concentrations of CMC-nZVI induced multigenerational reproductive toxicity which can be ascribed to its high production of ROS in F0 generation, toxicity of Fe(II)aq, and iron accumulation in C. elegans. Since nZVI is widely used for environmental remediation, considering the multigenerational toxicity, this study thus implicates a potential environmental risk of nZVI-induced nanotoxicity in the environment.
纳米零价铁（nZVI）被广泛大规模用于原位或异位环境修复应用。需要阐明环境相关浓度下nZVI对生物群的潜在影响。在本研究中，检测了三种铁物种：羧甲基纤维素（CMC）稳定的nZVI、纳米级氧化铁（nFe3O4）和亚铁离子（Fe(II)aq）对土壤线虫秀丽隐杆线虫的生殖毒性。此外，还研究了CMC-nZVI对秀丽隐杆线虫生殖毒性的代际传递。结果表明，在检测浓度下暴露24小时后，CMC-nZVI、nFe3O4和Fe(II)aq均未导致显著死亡率。生殖毒性试验表明，CMC-nZVI、nFe3O4和Fe(II)aq伴随着细胞内活性氧（ROS）的增加，显著降低了亲代（F0）的后代数量。此外，环境相关浓度下CMC-nZVI的生殖毒性可从F0代传递至F1和F2代，但在F3和F4代恢复。进一步证据表明，CMC-nZVI亲代暴露后，总铁在秀丽隐杆线虫的F0和F1代中积累。本研究表明，环境相关浓度的CMC-nZVI诱导多代生殖毒性，这可归因于其在F0代中大量产生ROS、Fe(II)aq的毒性以及在秀丽隐杆线虫中的铁积累。由于nZVI被广泛用于环境修复，考虑到多代毒性，本研究因此暗示了nZVI在环境中诱导纳米毒性的潜在环境风险。
