Volatile matter at 135 °C (275 °F), not more than 1.5 percent.
Matter insoluble in toluene, not more than 1.5 percent.
2-Chloro-4-nitrobenzenamine, not more than 0.3 percent.
2-Naphthalenol, not more than 1 percent.
2,4-Dinitrobenzenamine, not more than 0.02 percent.
1-[(2,4-Dinitrophenyl)azo]-2-naphthalenol, not more than 0.5 percent.
4-[(2-Chloro-4-nitrophenyl)azo]-1-naphthalenol, not more than 0.5 percent.
1-[(4-Nitrophenyl)azo]-2-naphthalenol, not more than 0.3 percent.
1-[(4-Chloro-2-nitrophenyl)azo]-2-naphthalenol, not more than 0.3 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 95 percent.
21 C.F.R. §74.1336