Young Researchers Club, Science and Research Branch, Islamic Azad University, Tehran, Iran.
J Nanobiotechnology. 2012 Apr 2;10:14. doi: 10.1186/1477-3155-10-14.
To better understand the potential ecotoxicological impacts of silver nanoparticles released into freshwater environments, the Daphnia magna 48-hour immobilization test was used.
The toxicities of silver nitrate, two types of colloidal silver nanoparticles, and a suspension of silver nanoparticles were assessed and compared using standard OECD guidelines. Also, the swimming behavior and visible uptake of the nanoparticles by Daphnia were investigated and compared. The particle suspension and colloids used in the toxicity tests were well-characterized.
The results obtained from the exposure studies showed that the toxicity of all the silver species tested was dose and composition dependent. Plus, the silver nanoparticle powders subsequently suspended in the exposure water were much less toxic than the previously prepared silver nanoparticle colloids, whereas the colloidal silver nanoparticles and AgNO(3) were almost similar in terms of mortality. The silver nanoparticles were ingested by the Daphnia and accumulated under the carapace, on the external body surface, and connected to the appendages. All the silver species in this study caused abnormal swimming by the D. magna.
According to the present results, silver nanoparticles should be classified according to GHS (Globally Harmonized System of classification and labeling of chemicals) as "category acute 1" to Daphnia neonates, suggesting that the release of nanosilver into the environment should be carefully considered.
为了更好地了解银纳米粒子释放到淡水环境中可能产生的生态毒理学影响，采用大型溞 48 小时固定试验法进行了研究。
根据标准的 OECD 指南，评估并比较了硝酸银、两种类型的胶体银纳米粒子和银纳米粒子悬浮液的毒性。同时，还研究并比较了纳米粒子对大型溞的游泳行为和可见摄取情况。用于毒性试验的颗粒悬浮液和胶体均经过良好的特性描述。
暴露研究的结果表明，所有测试的银物种的毒性均取决于剂量和组成。此外，随后悬浮在暴露水中的银纳米粒子粉末的毒性明显低于先前制备的银纳米粒子胶体，而胶体银纳米粒子和 AgNO3 在死亡率方面几乎相似。纳米粒子被大型溞摄取，并在甲壳下、体表和附肢上积累。本研究中的所有银物种均导致大型溞出现异常游泳行为。
根据目前的结果，银纳米粒子应根据 GHS（全球化学品统一分类和标签制度）被归类为“对溞属幼虫急性 1 类”，这表明应谨慎考虑将纳米银释放到环境中。
