Authors: C. McCracken, A. Zane, D. Knight, P. Dutta, W.J. Waldman
Affilation: The Ohio State University, United States
Pages: 441 - 444
Keywords: toxicity, oral exposure, intestine, silica, titanium dioxide, zinc oxide
Oral exposure to nanoparticles incorporated in foods is increasingly common. However, the effects of these nanoparticles when ingested are still unknown. Thus, this investigation tested the hypothesis that nanoparticle toxicity is dependent on particle size, chemistry, and surface charge. This was done by designing studies to assess toxic effects on intestinal epithelial cells after both acute and chronic exposure. The inorganic nanoparticles SiO2, TiO2, and ZnO were investigated. Particles were treated with digestive enzymes to simulate in vivo digestion before exposing to cells. Acute studies in which intestinal epithelial cells were treated with nanoparticles for 24 hours revealed no toxicity as measured by several different assays. Chronic studies in which cells were repeatedly treated with nanoparticles after each successive cell passage also revealed no toxicity or change in cell proliferation up to 32 nanoparticle exposures. These studies suggest that the investigated nanoparticles are not directly toxic to intestinal epithelial cells, but it remains to be seen what effects these particles will have in vivo.