In Vivo Toxicity of 1-D Nanostructures

As noted above, all of the toxicological studies conducted to date have focused on the effect of Si02 nanowires on cells in various tissue culture systems, and have not explored the consequences of exposure in intact animal models. An extensive search of the available literature revealed that no reports have been made regarding the in vivo toxicity of 1-D silica nanomaterials. Here, we will instead briefly summarize the literature on the in vivo toxicity of related materials, making predictions based not only on these studies but also on those focusing on particles and 1-D silica nanomaterials in cell culture. 

Potential exposure routes for siUca nanowires include the skin and mucosal membranes, as weU as intentional internal exposure for proposed biomedical purposes. The inhalational toxicity of silica and siUca-based materials is weU known and has been extensively reviewed [58-60]. CrystalUne silica, a multidimen- 

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