In summary, the Food Directorate's position is that there is no conclusive scientific evidence that the food additive TiO₂ is a concern for human health. This is based on a review of the available scientific data relevant to food uses of TiO₂. However, we will continue to monitor the emerging science on the safety of TiO₂ as a food additive and may revisit our position if new scientific information becomes available.

Titanium Dioxide Description

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. 

Barium sulfide is produced by carbothermic reduction of barium sulfate. Zinc sulfate is obtained from a variety of zinc products, often waste, by treatment with sulfuric acid.