This HOT article from Birgit Gaiser (Edinburgh Napier University) and colleagues presents a detailed study into the effect of silver and cerium dioxide nanoparticles on the common freshwater test organism Daphnia magna.
Both species of nanoparticles (NPs) are currently used extensively – silver in consumer products for their antibacterial properties, and cerium dioxide in slurries for silicon wafer planarization – and usage is only expected to increase. It is therefore essential to to assess their potentially damaging effects on the environment due to factors such as particle size, material, and concentration. This study investigated acute and chronic toxicity of well characterised nano- and micron- sized particles in Daphnia magna, confirming the “nano-hypothesis” – that nano-sized particles were more toxic than equal concentrations of micron-sized particles (for Ag NPs). Confirming previous studies, CeO2 NPs were only toxic at concentrations significantly above environmentally relevant levels. The study also uncovered sub-lethal effects of silver nanoparticles, such as moulting and impaired growth of D. magna, which the authors hope will improve our understanding of the mechanism that causes toxic effects.
This HOT article is part of our forthcoming themed issue on Environmental Nanotechnology and is free to access for 4 weeks. The careful characterisation of the nanoparticles makes this study particularly valuable – why not read Robert MacCuspie’s article on the challenges for physical characterization of silver nanoparticles which is also part of this themed issue.
Effects of silver and cerium dioxide micro- and nano-sized particles on Daphnia magna
Birgit K. Gaiser, Anamika Biswas, Philipp Rosenkranz, Mark A. Jepson, Jamie R. Lead, Vicki Stone, Charles R. Tyler and Teresa F. Fernandes
J. Environ. Monit., 2011, Advance Article
DOI: 10.1039/C1EM10060B, Paper
