Van Hoecke Karen, De Schamphelaere Karel A C, Van der Meeren Paul, Lucas Stéphane, Janssen Colin R
Laboratory of Environmental Toxicology and Aquatic Ecology, Faculty of Bioscience Engineering, Department of Applied Ecology and Environmental Biology, Ghent University (UGent), Jozef Plateaustraat 22, B-9000 Gent, Belgium.
Environ Toxicol Chem. 2008 Sep;27(9):1948-57. doi: 10.1897/07-634.1.
To date, (eco)toxicological information on industrial nanoparticles is very limited. In the present study, the hypothesis that the ecotoxicity of nanoparticles (NPs) is related to their surface area and not to their mass was tested using a freshwater green algal species. Particle diameter and morphology were assessed using light scattering and electron microscopy techniques. To assess the toxicity of silica (SiO2) nanoparticles, the growth inhibition of the alga Pseudokirchneriella subcapitata when exposed to stable silica suspensions was monitored. Commercial LUDOX suspensions of nanoparticles with 12.5 and 27.0 nm diameter were found to be toxic, with 72-h 20% effect concentrations for growth rate (E(r)C20) values +/- standard deviation (n = 5) of 20.0 +/- 5.0 and 28.8 +/- 3.2 mg/L, respectively. The toxicity was attributable to the solid nanospheres, because no aggregation was observed and dissolution of the nanoparticles was negligible. When expressing the concentration as a surface area, the difference in toxicity was not significant. In the latter case, 72-h E(r)C20 values +/- standard deviation (n = 5) were 4.7 +/- 1.2 and 3.9 +/- 0.4 m2/L. Silica bulk material was found to be nontoxic up to 1 g/L. In an additional experiment with 100 mg/L of 12.5 and 27.0 nm SiO2 NPs, the interaction between the nanoparticles and algal cells was studied using transmission electron microscopy. Although the particles clearly adhered to the outer cell surface, no evidence was found for particle uptake.
迄今为止，关于工业纳米颗粒的（生态）毒理学信息非常有限。在本研究中，使用一种淡水绿藻物种对纳米颗粒（NPs）的生态毒性与其表面积而非质量相关这一假设进行了测试。使用光散射和电子显微镜技术评估颗粒直径和形态。为了评估二氧化硅（SiO₂）纳米颗粒的毒性，监测了藻类小新月菱形藻（Pseudokirchneriella subcapitata）在暴露于稳定的二氧化硅悬浮液时的生长抑制情况。发现直径为12.5和27.0 nm的商用LUDOX纳米颗粒悬浮液具有毒性，生长速率的72小时20%效应浓度（E(r)C20）值±标准偏差（n = 5）分别为20.0±5.0和28.8±3.2 mg/L。毒性归因于固体纳米球，因为未观察到聚集且纳米颗粒的溶解可忽略不计。当将浓度表示为表面积时，毒性差异不显著。在后一种情况下，72小时E(r)C20值±标准偏差（n = 5）为4.7±1.2和3.9±0.4 m²/L。发现二氧化硅块状材料在浓度高达1 g/L时无毒。在一项使用100 mg/L的12.5和27.0 nm SiO₂ NPs进行的额外实验中，使用透射电子显微镜研究了纳米颗粒与藻类细胞之间的相互作用。尽管颗粒明显附着在细胞外表面，但未发现颗粒被摄取的证据。
