③ Paper making industry: Paper making and paper products industry is the third largest application industry of titanium dioxide. Paper using titanium dioxide has good whiteness, high strength, luster, thin and smooth, and is not easy to penetrate when printing. Under the same conditions, the opacity is 10 times higher than that of paper using calcium carbonate and talc powder, and the weight can also be reduced by 15% to 30%. The amount of titanium dioxide in decorative paper accounts for 20%~40% of its raw materials, and the amount of titanium dioxide in other papers is about 1%~5%. Due to the continuous adjustment of the industrial structure of the paper products industry from 2016 to 2018, according to the data of China Paper Association, the output of China's paper products in 2019 was 72.19 million tons, a significant year-on-year increase of 29.4%, and the use of titanium dioxide increased significantly.

The most significant uncertainty identified by the EU experts was the concern that TiO₂ particles may have genotoxic effects. Genotoxicity refers to the ability of a chemical to directly damage genetic material within a cell (DNA), which may lead to cancer in certain situations. Although the experts did not conclude that TiO₂ particles in E171 are genotoxic, they could not rule out the concern that they might be.