Nanotechnology has evolved to play a prominent role in our economy. Increased use of nanomaterials poses potential human health risk. It is therefore critical to understand the nature and origin of the toxicity imposed by nanomaterials (nanotoxicity). In this article we review the toxicity of the transition metal oxides in the 4th period that are widely used in industry and biotechnology. Nanoparticle toxicity is compellingly related to oxidative stress and alteration of calcium homeostasis, gene expression, pro-inflammatory responses, and cellular signaling events. The precise physicochemical properties that dictate the toxicity of nanoparticles have yet to be defined, but may include element-specific surface catalytic activity (e.g., metallic, semiconducting properties), nanoparticle uptake, or nanoparticle dissolution. These in vitro studies substantially advance our understanding in mechanisms of toxicity, which may lead to safer design of nanomaterials.


Biological Sciences

Keywords and Phrases

Calcium Homeostasis; Metal Oxides; Nanoparticle Toxicity; Physicochemical Property; Semi-Conducting Property; Surface Catalytic Activity; Transition Metal Oxide Nanoparticles; Transition-Metal Oxides; Calcium; Gene Expression; Nanoparticles; Nanostructured Materials; Oxidative Stress; Physiology; Signal Transduction; Toxicity

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Article - Journal

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Final Version

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© 2010 The Authors, All rights reserved.

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This work is licensed under a Creative Commons Attribution 3.0 License.

Publication Date

01 Oct 2010

PubMed ID


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