Increasing use of titanium dioxide (TiO2) nanoparticles in many commercial applications led to emerging concerns regarding the safety and environmental impact of these materials. The authors have studied the biological impact of nano-TiO2 (with particle primary size of 20 nm Aeroxide P25) on human lung cell lines in vitro and also the effect of particle size distribution on the particle uptake and apparent toxicity. The biological impact of nano-TiO2 is influenced by the concentration and particle size distribution of the TiO2 and the impact was shown to differ between the two cell lines (A549 and H1299) studied herein. A549 cell line is relatively resistant to the total amount of TiO2 particles uptaken, as measured by cell viability and metabolic assays, while H1299 had a much higher capacity to ingest TiO2 particles and aggregates, with consequent evidence of impact at concentrations of 30-150 íg/mL TiO2. Evidence gathered from this study suggests that both viability and metabolic assays (measuring metabolic and mitochondrial activities and also cellular ATP level) should be carried out collectively to gain a true assessment of the impact of exposure to TiO2 particles.
Authors: Tedja, Roslyn; Marquis, Christopher; Lim, May; Amal, Rose ;Full Source: Journal of Nanoparticle Research 2011, 13(9), 3801-3813 (Eng) ;