4种纳米氧化铁对大型蚤的急性毒性

Acute Toxicity of Nano-Sized Oxides to Daphnia magna

为了评价纳米氧化铁材料的水生态安全性,参照国家化学品生态毒性测试标准方法(GB/T13266-91),以大型蚤(Daphniamagna)为受试生物,研究了4种纳米氧化铁水悬浮液(nα-FeOOH:针状,15 nm;nFe3O4:球形,9 nm;nα-Fe2O3:近球形和纺锤形,40 nm;nγ-Fe2O3:针形和近球形,22 nm)对水生甲壳类动物大型蚤的毒性效应。结果显示,4种纳米氧化铁水悬浮液对大型蚤活动抑制的48 h EC50值分别为:0.267、0.097、3.717 mg/L,>100.0 mg/L。据此可得到4种氧化铁纳米材料的毒性大小顺序为:nFe3O4>nα-FeOOH>nα-Fe2O3>nγ-Fe2O3。通过对4种纳米氧化铁水生态安全性的初步评价,表明人工纳米材料的生态毒性和环境效应不容忽视,应重视并深入研究其制毒作用机制。

To examine the impact of nano-sized oxides on the aquatic eco-system, a laboratory experiment was conducted according to the state guidelines for testing of chemicals （GB/T 13266-91 ）. Daphnia magna was adopted as testing aquatic organisms and four kinds of nano-iron oxides with different shapes and sizes, i.e. nα-FeOOH, nFe3O4, nα-Fe2O3 and nγ- Fe2O3, were used to test their toxicities to Daphnia magna. Suspensions were prepared which consisted of the four nano-iron oxides respectively. Results of the experiment presented the values of 48 h ECho of the four nano-iron oxides, evaluating their toxicity levels, It was concluded that from the point of ecological security, more attention should be paid to the nano- materials in terms of their ecological toxicity and environmental impact.