[Code of Federal Regulations]
[Title 21, Volume 6]
[Revised as of April 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 21CFR500.86]

[Page 13-14]
 
                        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. 500.86  Marker residue and target tissue.

    (a) For each edible tissue, the sponsor shall measure the depletion 
of the

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residue of carcinogenic concern until its concentration is at or below 
Sm.
    (b) In one or more edible tissues, the sponsor shall also measure 
the depletion of one or more potential marker residues until the 
concentration of the residue of carcinogenic concern is at or below 
Sm.
    (c) From these data, FDA will select a target tissue and a marker 
residue and designate the concentration of marker residue 
(Rm) that the regulatory method must be capable of measuring 
in the target tissue. FDA will select Rm such that the 
absence of the marker residue in the target tissue above Rm 
can be taken as confirmation that the residue of carcinogenic concern 
does not exceed Sm in each of the edible tissues and, 
therefore, that the residue of carcinogenic concern in the diet of 
people does not exceed So.
    (d) When a compound is to be used in milk- or egg-producing animals, 
milk or eggs must be the target tissue in addition to the tissue 
selected to monitor for residues in the edible carcass.

(Approved by the Office of Management and Budget under control number 
0910-0228)