CSPI says it might reconsider its rating if specifications for food-grade titanium dioxide in the U.S. are updated to ensure nanoparticles are minimized, and new studies are conducted to assess its capacity to cause cancer or other health problems. 

Prof Matthew Wright, both a member of the FAF Panel and chair of EFSA’s working group on E 171, said: “Although the evidence for general toxic effects was not conclusive, on the basis of the new data and strengthened methods we could not rule out a concern for genotoxicity and consequently we could not establish a safe level for daily intake of the food additive.”

Solids were stable and did not show visible signs or changes in their spectra after being kept at room temperature for over 60 days. The absorbance at the maximum absorbance wavelength remained unmodified.

A 2022 review on past studies of titanium dioxide and rat lung cancer, for instance, said the original study was under extreme conditions and its effects were not replicated in other animal species. Additionally, the review concluded that the few studies which did directly focus on titanium dioxide's impact on humans did not end up showing any increased cancer risk.

Titanium dioxide goes into many industrial and consumer products. It makes paper white and bright, it keeps plastics and rubber soft and flexible, and helps remove harmful emissions from car exhaust, among many other uses. In the drug industry, it's a key ingredient in pill capsules and tablet coatings to keep the medicine inside from being affected by sunlight. 

Fig. 6. AOPP measured on samples of MSSA with: A) 0.2 mg/mL P25TiO₂NPs; B) 0.02 mg/mL P25TiO₂NPs; C) 0.2 mg/mL VitaminB2@P25TiO₂NPs; D) 0.02 mg/mL VitaminB2@P25TiO₂NPs after 3 h of irradiation (red) and 6 h (blue). SD <1 (error bars too small to be seen) and p < 0.05 between C-D and A-B.

The FDA has issued guidance clarifying the safe use of titanium dioxide pigment as a food colorant and has stated that titanium dioxide may be safely used in cosmetics, including those intended for use around the eye. FDA also regulates the safety and effectiveness of sunscreen active ingredients, including nanoscale titanium dioxide.

Lithopone can also be used as raw material of putty to fill gaps; Adding 20% lithopone to the concrete to make artificial quartz without harming its light resistance and solidification; It can improve the impact resistance and electrical performance when used in fire safety polyester chemicals; These are the raw materials of audio vinyl records used for turbojet engine dye and thermal insulation coating and insulating layer.