(a) Identity.

1. (1) The color additive titanium dioxide is synthetically prepared TiO2, free from admixture with other substances.
2. (2) Color additive mixtures for food use made with titanium dioxide may contain only those diluents that are suitable and that are listed in this subpart as safe in color additive mixtures for coloring foods, and the following: Silicon dioxide, SiO2 and/or aluminum oxide, Al2 O3, as dispersing aids—not more than 2 percent total.

(b) Specifications. Titanium dioxide shall conform to the following specifications:

Lead (as Pb), not more than 10 parts per million. Arsenic (as As), not more than 1 part per million. Antimony (as Sb), not more than 2 parts per million. Mercury (as Hg), not more than 1 part per million. Loss on ignition at 800 °C. (after drying for 3 hours at 105 °C.), not more than 0.5 percent. Water soluble substances, not more than 0.3 percent. Acid soluble substances, not more than 0.5 percent. TiO2, not less than 99.0 percent after drying for 3 hours at 105 °C.

Lead, arsenic, and antimony shall be determined in the solution obtained by boiling 10 grams of the titanium dioxide for 15 minutes in 50 milliliters of 0.5N hydrochloric acid.

(c) Uses and restrictions. The color additive titanium dioxide may be safely used for coloring foods generally, subject to the following restrictions:

1. (1) The quantity of titanium dioxide does not exceed 1 percent by weight of the food.
2. (2) It may not be used to color foods for which standards of identity have been promulgated under section 401 of the act unless added color is authorized by such standards.