[Code of Federal Regulations]
[Title 21, Volume 6]
[Revised as of January 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR500.82]

[Page 12-13]
 
                        TITLE 21--FOOD AND DRUGS
 
CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN 
                          SERVICES (CONTINUED)
 
PART 500--GENERAL--Table of Contents
 
 Subpart E--Regulation of Carcinogenic Compounds Used in Food-Producing 
                                 Animals
 
Sec.  500.82  Definitions.

    (a) The definitions and interpretations contained in section 201 of 
the act apply to those terms when used in this subpart.
    (b) The following definitions apply to this subpart:
    Act means the Federal Food, Drug, and Cosmetic Act (sections 201-
901, 52 Stat. 1040 et seq. as amended (21 U.S.C. 301-392)).
    Essential nutrients means compounds that are found in the tissues of 
untreated, healthy target animals and not produced in sufficient 
quantity to support the animal's growth, development, function, or 
reproduction, e.g., vitamins, essential minerals, essential amino acids, 
and essential fatty acids. These compounds must be supplied from 
external sources.
    FDA means the Food and Drug Administration.
    Limit of detection (LOD) means the lowest concentration of analyte 
that can be confirmed by the approved regulatory method.
    Marker residue means the residue selected for assay whose 
concentration is in a known relationship to the concentration of the 
residue of carcinogenic concern in the last tissue to deplete to its 
Sm.

[[Page 13]]

    Preslaughter withdrawal period or milk discard time means the time 
after cessation of administration of the sponsored compound at which no 
residue is detectable in the edible product using the approved 
regulatory method (i.e., the marker residue is below the LOD).
    Regulatory method means the aggregate of all experimental procedures 
for measuring and confirming the presence of the marker residue of the 
sponsored compound in the target tissue of the target animal.
    Rm means the concentration of the marker residue in the 
target tissue when the residue of carcinogenic concern is equal to 
Sm.
    Residue means any compound present in edible tissues of the target 
animal which results from the use of the sponsored compound, including 
the sponsored compound, its metabolites, and any other substances formed 
in or on food because of the sponsored compound's use.
    Residue of carcinogenic concern means all compounds in the total 
residue of a demonstrated carcinogen excluding any compounds judged by 
FDA not to present a carcinogenic risk.
    Sm means the concentration of residue in a specific 
edible tissue corresponding to a maximum lifetime risk of cancer in the 
test animals of 1 in 1 million.
    So means the concentration of the test compound in the 
total diet of test animals that corresponds to a maximum lifetime risk 
of cancer in the test animals of 1 in 1 million. For the purpose of this 
subpart, FDA will also assume that this So will correspond to 
the concentration of residue of carcinogenic concern in the total human 
diet that represents no significant increase in the risk of cancer to 
people.
    Sponsor means the person or organization proposing or holding an 
approval by FDA for the use of a sponsored compound.
    Sponsored compound means any drug or food additive or color additive 
proposed for use, or used, in food-producing animals or in their feed.
    Target animals means the production class of animals in which a 
sponsored compound is proposed or intended for use.
    Target tissue means the edible tissue selected to monitor for 
residues in the target animals, including, where appropriate, milk or 
eggs.
    Test animals means the species selected for use in the toxicity 
tests.
    Threshold assessment means FDA's review of data and information 
about a sponsored compound to determine whether chronic bioassays in 
test animals are necessary to resolve questions concerning the 
carcinogenicity of the compound.

[52 FR 49586, Dec. 31, 1987, as amended at 67 FR 78174, Dec. 23, 2002]