Ecotoxicity of silica nanoparticles to the green alga pseudokirchneriella subcapitata: Importance of surface area
- 1 September 2008
- journal article
- Published by Wiley in Environmental Toxicology and Chemistry
- Vol. 27 (9), 1948-1957
- https://doi.org/10.1897/07-634.1
Abstract
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 (R) 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 m(2)/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 uptakeKeywords
This publication has 29 references indexed in Scilit:
- Quantitative and qualitative studies of silica in different rice samples grown in north of Iran using UV–vis, XRD and IR spectroscopy techniquesTalanta, 2006
- Pulmonary Bioassay Studies with Nanoscale and Fine-Quartz Particles in Rats: Toxicity is Not Dependent upon Particle Size but on Surface CharacteristicsToxicological Sciences, 2006
- Toxic Potential of Materials at the NanolevelScience, 2006
- The bactericidal effect of silver nanoparticlesNanotechnology, 2005
- Nanotoxicology: An Emerging Discipline Evolving from Studies of Ultrafine ParticlesEnvironmental Health Perspectives, 2005
- The potential environmental impact of engineered nanomaterialsNature Biotechnology, 2003
- The nucleation period for crystallization of colloidal TPA-silicalite-1 with varying silica sourceMicroporous and Mesoporous Materials, 2000
- Toxicology of ultrafine particles:in vivostudiesPhilosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2000
- A low-viscosity epoxy resin embedding medium for electron microscopyJournal of Ultrastructure Research, 1969
- Adsorption of Gases in Multimolecular LayersJournal of the American Chemical Society, 1938