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.

Nanotoxicology “focuses on determining the adverse effects of nanomaterials on human health and the environment.”

As a result, tariffs for titanium products are remaining similar to the ones in 2016, which will not cause bigger price fluctuations and keep a stable market.