(a) Identity.

1. (1) The color additive D&C Green No. 8 is principally the trisodium salt of 8-hydroxy-1,3,6-pyrene-trisulfonic acid.
2. (2) Color additive mixtures for use in externally applied drugs made with D&C Green No. 8 may contain only those diluents that are suitable and that are listed in part 73 of this chapter for use in color additive mixtures for coloring externally applied drugs.

(b) Specifications. D&C Green No. 8 shall conform to the following specifications and shall be free from impurities other than those named to the extent that such impurities may be avoided by good manufacturing practices:

Volatile matter (at 135 °C), not more than 15 percent. Water-insoluble matter, not more than 0.2 percent. Chlorides and sulfates (calculated as sodium salt), not more than 20 percent. The trisodium salt of 1,3,6-pyrenetrisulfonic acid, not more than 6 percent. The tetrasodium salt of 1,3,6,8-pyrenetetrasulfonic acid, not more than 1 percent. Pyrene, not more than 0.2 percent. Lead (as Pb), not more than 20 parts per million. Arsenic (as As), not more than 3 parts per million. Mercury (as Hg), not more than 1 part per million. Total color, not less than 65 percent.