{"data":{"id":"us/21-cfr-556.283","jurisdiction":"us","citation":"21 CFR 556.283","heading":"Florfenicol.","body":"(a) Acceptable daily intake (ADI). The ADI for total residue of florfenicol is 10 µg/kg of body weight per day.\n(b) Tolerances. The tolerances for florfenicol amine (marker residue) are:\n(1) Cattle. (i) Liver (target tissue): 3.7 ppm.\n(ii) Muscle: 0.3 ppm.\n(2) Swine. (i) Liver (target tissue): 2.5 ppm.\n(ii) Muscle: 0.2 ppm.\n(3) Catfish. Muscle (target tissue): 1 ppm.\n(4) Freshwater-reared warmwater finfish (other than catfish) and salmonids. Muscle/skin (target tissue): 1 ppm.\n(c) Related conditions of use. See §§ 520.955, 522.955, 522.956, and 558.261 of this chapter.","path":["Title 21—Food and Drugs","CHAPTER I—FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES","SUBCHAPTER E—ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS","PART 556—TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD","Subpart B—Specific Tolerances for Residues of Approved and Conditionally Approved New Animal Drugs"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-21.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:24:47Z","sha256":"99704dd268cef56952008e6c8d4f7c928c315ae9da91fe979be1bb29ce0be8f8","source_id":"us-cfr","stale":true,"prev":"us/21-cfr-556.280","next":"us/21-cfr-556.286"},"notice":"GroundRules: Original legal text. Not legal advice."}