[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: 21CFR579.22] [Page 506] TITLE 21--FOOD AND DRUGS CHAPTER I--FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES--(Continued) PART 579--IRRADIATION IN THE PRODUCTION, PROCESSING, AND HANDLING OF ANIMAL FEED AND PET FOOD--Table of Contents Subpart B--Radiation and Radiation Sources Sec. 579.22 Ionizing radiation for treatment of laboratory animal diets. Ionizing radiation for treatment of complete diets for laboratory animals (mice, rats, and hamsters) may be safely used under the following conditions: (a) Energy sources. Ionizing radiation is limited to: (1) Gamma rays for sealed units of the radionuclides cobalt-60 or cesium-137. (2) Electrons generated from machine sources at energy levels not to exceed 10 million electron volts. (b) Uses. The ionizing radiation is used or intended for use in single treatment as follows: ------------------------------------------------------------------------ Food for irradiation Limitations Use ------------------------------------------------------------------------ Bagged complete diets for Absorbed dose: Not Microbial laboratory animals (mice, rats, to exceed 50 disinfection. hamsters, rabbits, and guinea kiloGrays (5 pigs). megarads) Feeds treated by irradiation should be formulated to account for nutritional loss.. ------------------------------------------------------------------------ [51 FR 5993, Feb 19, 1986; 51 FR 8315, Mar. 11, 1986, as amended at 58 FR 18148, Apr. 8, 1993]