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.

The FDA first approved the use of titanium dioxide in food in 1966, following its 1960 removal (along with the removal of other color additives) from the agency's original Generally Recognized as Safe list. In 1977, titanium dioxide joined the list of color additives that are exempt from certification, which means titanium dioxide doesn't have to be listed on the packaging of every product it's used in, Faber noted.

3. UV Protection Tires are constantly exposed to harsh environmental conditions, including ultraviolet (UV) rays from the sun. Titanium dioxide provides excellent UV protection, minimizing degradation caused by prolonged exposure. This property ensures that tires maintain their integrity and performance over time, leading to a longer lifespan.

Moreover, titanium dioxide is also used in rubber formulations to improve the processing and curing properties of rubber compounds. It acts as a catalyst in the vulcanization process, speeding up the cross-linking of rubber molecules and enhancing the overall performance of the final product. This results in rubber products that are stronger, more flexible, and better suited for a wide range of applications.