From Spacemart:

The impact of nanoparticle interactions with the body are dependent on their size, chemical composition, surface structure, solubility, shape, and how the individual nanoparticles amass together, according to Nel. Nanoparticles may modify the way cells behave and potential routes of exposure, include the gastrointestinal tract, skin and lungs. The three key elements of the toxicity screening strategy should include the physical and chemical characterization of nanomaterials, tissue cellular assays and animal studies. "An understanding of nanotoxicity could also lead to the harnessing of their properties such as using nanoparticles that initiate cell death to be used for targeted chemotherapy approaches," said Nel, who also leads the Cellular Immunology Activation Laboratory in the Jonsson Cancer Center at UCLA.

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