[I]ts light-scattering properties and very high , which mean that rela — Titanium dioxide

"Titanium dioxide was first produced commercially in 1923, primarily for pigment production. Relatively small quantities are used for non-pigmentary purposes."

"TiO2 has been classified in humans and animals as biologically inert... and is widely considered to be a "natural" material..."

"The annual worldwide production of titania powder in 2005 has been estimated to be around 5 million tons... The proportion of nano-sized titania is estimated to have been approximately... 10% by 2015... with an exponential increase over the past decade."

"Exposure levels [to titanium dioxide]... are assumed to be low... with the possible exception of workers who handle large quanities... No significant exposure... is thought to occur during the use of products in which titanium dioxide is bound to other materials, such as paints."

"In two studies of rats that inhaled titanium dioxide, one observed an excess incidence of lung tumours... No increases were observed among mice and hamsters exposed intratracheally. Other studies that used different routes of administration did not observe excesses in tumour incidence."

"Most titanium dioxide pigment is produced from mineral concentrates by the chloride or sulfate process, either as the rutile or as the anatase form."