StacksVerified U.S. regulatory reference

21 CFR §556.283

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)Acceptable daily intake (ADI). The ADI for total residue of florfenicol is 10 µg/kg of body weight per day.
  2. (b)Tolerances. The tolerances for florfenicol amine (marker residue) are:
    1. (1)Cattle.
      1. (i)Liver (target tissue): 3.7 ppm.
      2. (ii)Muscle: 0.3 ppm.
    2. (2)Swine.
      1. (i)Liver (target tissue): 2.5 ppm.
      2. (ii)Muscle: 0.2 ppm.
    3. (3)Catfish. Muscle (target tissue): 1 ppm.
    4. (4)Freshwater-reared warmwater finfish (other than catfish) and salmonids. Muscle/skin (target tissue): 1 ppm.
  3. (c)Related conditions of use. See §§ 520.955, 522.955, 522.956, and 558.261 of this chapter.