Saturday May 28, 2016 (foodconsumer.org) -- Titanium dioxide in the form of nanoparticles is genotoxic and cytotoxic after it enters our systems as many animal studies have demonstrated.  Still, this material is commonly used in processed foods, dietary supplements and cosmetic products.

A new study led by researchers at Mahidol University in Bangkok, Thailand shows that titanium dioxide can injure human blood cells called peripheral blood mononuclear cells (PBMCs) in serum free medium, suggesting that it may damage blood cells in vivo.

For the study, PBMCs were treated with titanium dioxide at concentrations of 25 micrograms per milliliter or higher concentrations for 24 hours.  As a result, titanium dioxide induced the production of reactive oxygen species (ROS), which can cause DNA damage and inflammatory response.   It was also observed that cells started to die after exposure to titanium dioxide at the tested concentrations.

The size of titanium dioxide nanoparticles used for the test was 26.4 nm.  Nanoparticles of this size and even bigger sizes can get into cells and disrupt DNA, potentially injuring DNA and leading to mutagenesis.   Other nanoparticles such as zinc oxide and silica commonly used in foods, supplements and cosmetic products are also genotoxic and cytotoxic.  (David Liu)

Source: Kongseng S, Yoovathaworn K, Wongprasert K, Chunhabundit R, Sukwong P, Pissuwan D,  Cytotoxic and inflammatory responses of TiO2 nanoparticles on human peripheral blood mononuclear cells.  J Appl Toxicol. 2016 May 25. doi: 10.1002/jat.3342.