Volatile matter (at 135 °C.), not more than 6.0 percent.
Chlorides and sulfates (calculated as the sodium salts), not more than 7.0 percent.
Water insoluble matter, not more than 0.2 percent.
1-(4-Sulfophenyl)-3-ethylcarboxy-5-hydroxypyrazolone and 1-(4-sulfophenyl)-3-carboxy-5-hydroxypyrazolone, not more than 0.7 percent.
Naphthionic acid, not more than 0.2 percent.
Phenylhydrazine-p-sulfonic acid, not more than 0.2 percent.
The trisodium salt of 1-(4-sulfophenyl)-3-carboxy-4-(4-sulfonaphthylazo)-5-hydroxypyrazole, not more than 6.0 percent.
Other subsidiary dyes, not more than 1.0 percent.
Lead (as Pb), not more than 10 parts per million.
Arsenic (as As), not more than 1 part per million.
Total color, not less than 87.0 percent.
21 C.F.R. §74.250