[Code of Federal Regulations]
[Title 21, Volume 1]
[Revised as of April 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR74.1104]

[Page 393]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                                SERVICES
 
PART 74--LISTING OF COLOR ADDITIVES SUBJECT TO CERTIFICATION--Table of Contents
 
                            Subpart B--Drugs
 
Sec. 74.1104  D&C Blue No. 4.

    (a) Identity. (1) The color additive D&C Blue No. 4 is principally 
the diammonium salt of ethyl[4-[p[ethyl(m- sulfobenzyl)ami-no]-
-(o- sulfophenyl)benzylidene]-2,5-cyclo-hexadien-1-ylidene] (m- 
sulfobenzyl) ammonium hydroxide inner salt with smaller amounts of the 
isomeric diammonium salts of ethyl [4-[p-[ethyl(p- sulfobenzyl) amino]-
-(o- sulfophenyl) benzylidene]-2,5-cyclohexadien - 1-
ylidene](p- sulfobenzyl) ammonium hydroxide inner salt and ethyl[4-[p-
[ethyl (o- sulfobenzyl)amino]--(o- sulfophenyl) benzylidene]-
2,5-cyclohexadien-1-ylidene] (o- sulfobenzyl) ammonium hydroxide inner 
salt.
    (2) Color additive mixtures for use in externally applied drugs made 
with D&C Blue No. 4 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 Blue No. 4 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 
practice:

Sum of volatile matter (at 135  deg.C) and chlorides and sulfates 
(calculated as sodium salts), not more than 15 percent.
Water-insoluble matter, not more than 0.2 percent.
Leuco base, not more than 5 percent.
Sum of o-, m, and p- sulfobenzaldehydes, ammonium salt, not more than 
1.5 percent.
N-ethyl, N-(m- sulfobenzyl) sulfanilic acid ammonium salt, not more than 
0.3 percent.
Subsidiary colors, not more than 6 percent.
Chromium (as Cr), not more than 50 parts per million.
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 85 percent.

    (c) Uses and restrictions. D&C Blue No. 4 may be safely used in 
externally applied drugs in amounts consistent with good manufacturing 
practice.
    (d) Labeling. The label of the color additive and any mixtures 
prepared therefrom intended solely or in part for coloring purposes 
shall conform to the requirements of Sec. 70.25 of this chapter.
    (e) Certification. All batches of D&C Blue No. 4 shall be certified 
in accordance with regulations in part 80 of this chapter.