In 2022, a year after the EFSA recommended against the use of E171, the Food Standards Australia New Zealand (FSANZ) conducted its own reassessment of titanium dioxide as a food additive. The agency concluded that titanium dioxide was indeed safe to use as a food additive. The United Kingdom and Canada came to similar conclusions.

Additionally, the committee noted that the available data did not provide convincing evidence of genotoxicity for titanium dioxide as a food additive, but recognized the limitations in current methodologies with respect to the testing of poorly soluble particulate materials. Although there were uncertainties in the genotoxicity data, the experts took into account the fact that the additive was not carcinogenic in adequately conducted two-year studies in mice and rats at doses of up to 7,500 mg/kg BW per day for mice, and 2,500 mg/kg BW per day for rats, the highest doses tested. There was also no evidence of reproductive or developmental toxicity in studies in rats at doses up to 1,000 mg/kg BW per day, the highest doses tested.  

The assessment was conducted following a rigorous methodology and taking into consideration many thousands of studies that have become available since EFSA’s previous assessment in 2016, including new scientific evidence and data on nanoparticles. 

Although barium sulfate is almost completely inert, zinc sulfide degrades upon exposure to UV light, leading to darkening of the pigment. The severity of this UV reaction is dependent on a combination of two factors; how much zinc sulfide makes up the pigments formulation, and its total accumulated UV exposure. Depending on these factors the pigment itself can vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant may be used, such as a small amount of cobalt salts, which would be added to the formulation. This process creates cobalt-doped zinc sulfide. The cobalt salts help to stabilize zinc sulfide so it will not have as severe a reaction to UV exposure.

French researchers studied how and where E171 nanoparticles enter the bloodstream, first studying the route through pigs and then in vitro with human buccal cells, for a 2023 study published in the journal Nanotoxicology. The research showed that the nanoparticles absorbed quickly through the mouth and then into the bloodstream, before damaging DNA and hindering cell regeneration.

Titanium dioxide is found in pretty much all makeup & sunscreen.

And studies have long shown that products applied to the skin end up in the bloodstream within half an hour. With penetration rates depending on where they are applied. Absorption rates for your face & scalp are 5-10 times higher than on other parts of our body (Hotchkiss 1994).

Not to mention that in 2005, the Environmental Working Group published a combination of two studies that found toxic chemicals in the umbilical cord blood of newborn babies born in the U.S. They screened for more than 400 chemicals, and an astounding 287 toxins were detected within the umbilical cord blood of these newborns. Of these 287 chemicals, 217 were neurotoxins, and 208 are known to damage growth development or cause birth defects.

I don't see the scientific evidence in the literature that would cause people any concern, said Kaminski.

Animal studies show exposure to titanium dioxide is linked to immunotoxicity, inflammation and neurotoxicity.