[Code of Federal Regulations]
[Title 21, Volume 3]
[Revised as of April 1, 2005]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR189.190]

[Page 595-596]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 189_SUBSTANCES PROHIBITED FROM USE IN HUMAN FOOD--Table of Contents
 
Subpart C_Substances Generally Prohibited From Direct Addition or Use as 
                               Human Food
 
Sec. 189.190  Thiourea.

    (a) Thiourea is the chemical thiocarbamide, 
CH4N2S. It is a synthetic chemical, is not found 
in natural products at levels detectable by the official methodology, 
and has been proposed as an antimycotic for use in dipping citrus.
    (b) Food containing any added or detectable level of thiourea is 
deemed to be adulterated under the act.

[[Page 596]]

    (c) The analytical methods used for detecting thiourea are in 
sections 20.115-20.126 of the ``Official Methods of Analysis of the 
Association of Official Analytical Chemists,'' 13th Ed. (1980), which is 
incorporated by reference. Copies may be obtained from the Association 
of Official Analytical Chemists International, 481 North Frederick Ave., 
suite 500, Gaithersburg, MD 20877-2504, or may be examined at the 
National Archives and Records Administration (NARA). For information on 
the availability of this material at NARA, call 202-741-6030, or go to: 
http://www.archives.gov/federal--register/code--of--federal--
regulations/ibr--locations.html.

[42 FR 14659, Mar. 15, 1977, as amended at 49 FR 10114, Mar. 19, 1984; 
54 FR 24900, June 12, 1989]