While IARC listed titanium dioxide as “possibly carcinogenic to humans,” they also add that “there is inadequate evidence in humans for the carcinogenicity of titanium dioxide.” Of the four human studies that they reviewed, only one showed a potential risk for occupational workers inhaling titanium dioxide particles and lung cancer, while the other three showed no risk for cancer at all. And it’s key to note that IARC did not assess the effects of titanium dioxide found in foods.
In 2021, the European Food Safety Authority concluded that titanium dioxide is no longer safe in foods due to the same concerns over nanoparticles. As a result, titanium dioxide is now banned as a food additive in the EU. Although studies have shown that the absorption of ingested titanium dioxide is low, evidence suggests that titanium dioxide nanoparticles can accumulate in the body over time. Health Canada deemed it safe in 2022 but noted concerns. Unlike their European counterparts, Canadian officials did not consider studies performed with titanium dioxide nanoparticles alone.
