Novak S, Drobne D, Valant J, Pipan-Tkalec Ž, Pelicon P, Vavpetič P, Grlj N, Falnoga I, Mazej D, Remškar M
[ pdf ] [ site ] Environmental Toxicology and Chemistry, 2012

The present study was motivated by the paucity of reports on cellular internalization of ingested titanium dioxide (TiO₂) nanoparticles (nano-TiO₂). The model invertebrate (Porcellio scaber, Isopoda, Crustacea) was exposed to food dosed with nano-TiO₂ containing 100, 1,000, 3,000, or 5,000 µg nano-TiO₂ per gram of food. After 14 d of exposure, the amount of Ti in the entire body was analyzed by inductively coupled plasma–mass spectrometry, and elemental analyses of tissue cross sections were performed by particle induced X-ray emission. In addition, a series of toxicological markers including feeding parameters, weight change, and survival, as well as cytotoxic effects such as digestive gland cell membrane stability, were monitored. Internalization of ingested nano-TiO₂ by the isopod\’s digestive gland epithelial cells was shown to depend on cell membrane integrity. Cell membranes were found to be destabilized by TiO₂ particles, and at higher extracellular concentrations of nano-TiO₂, the nanoparticles were internalized.