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Title 21

Displaying title 21, up to date as of 8/13/2026. Title 21 was last amended 8/12/2026.
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Subpart F—Methods for Detection of Residues of Carcinogenic Compounds Used in Food-Producing Animals

Source:

76 FR 72618, Nov. 25, 2011, unless otherwise noted.

§ 500.1410 N-methyl-2-pyrrolidone.

(a) Standard for residues. No residues of n-methyl-2-pyrrolidone may be found in the uncooked edible tissues of cattle and swine as determined by methods in paragraph (b) of this section.

(b) Incorporation by reference. The standards required in this section are incorporated by reference into this section with the approval of the Director of the Federal Register under 5 U.S.C. 552(a) and 1 CFR part 51. All approved material is available for inspection at the Food and Drug Administration's Dockets Management Staff (HFA-305), 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852, 240-402-7500, between 9 a.m. and 4 p.m., Monday through Friday. It may be obtained from the sources indicated elsewhere in paragraph (b) of this section and at: https://www.fda.gov/about-fda/center-veterinary-medicine/cvm-foia-electronic-reading-room. It is also available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email , or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

(1) Food and Drug Administration, Center for Veterinary Medicine, 7500 Standish Pl., Rockville, MD 20855, 240-402-7002.

(i) “Method of Analysis: N-methyl-2-pyrrolidone,” September 26, 2011; the method of analysis for uncooked edible tissues of cattle.

(ii) [Reserved]

(2) Merck Animal Health, 29160 Intervet Lane, Millsboro, DE 19966, 1-800-211-3573.

(i) “Determinative and Confirmatory Procedures for the Analysis of N-Methyl-2-pyrrolidone (NMP) in Swine Liver Tissue using LC-MS/MS,” July 20, 2017; the method of analysis for uncooked edible tissues of swine.

(ii) [Reserved]

(c) Related conditions of use. See §§ 522.814, 522.955, and 522.1660a of this chapter.

[87 FR 10966, Feb. 28, 2022, as amended at 88 FR 55562, Aug. 16, 2023]