---
kind: "section"
citation: "21 C.F.R. § 556.283"
title: "21"
number: "556.283"
heading: "Florfenicol."
url: "https://uscodex.org/cfr/21/556.283"
---

# §556.283. Florfenicol.

- (a) **Acceptable daily intake (ADI).** The ADI for total residue of florfenicol is 10 µg/kg of body weight per day.
- (b) **Tolerances.** The tolerances for florfenicol amine (marker residue) are:
  - (1) **Cattle.**
    - (i) **Liver (target tissue)—** 3.7 ppm.
    - (ii) **Muscle—** 0.3 ppm.
  - (2) **Swine.**
    - (i) **Liver (target tissue)—** 2.5 ppm.
    - (ii) **Muscle—** 0.2 ppm.
  - (3) **Catfish.** Muscle (target tissue): 1 ppm.
  - (4) **Freshwater-reared warmwater finfish (other than catfish) and salmonids.** Muscle/skin (target tissue): 1 ppm.
- (c) **Related conditions of use.** See §§ [520.955](/cfr/21/520.955.md), [522.955](/cfr/21/522.955.md), [522.956](/cfr/21/522.956.md), and [558.261](/cfr/21/558.261.md) of this chapter.

## Notes

### Authority

Authority: 21 U.S.C. 342, 360b, 371.

### Source

Source: 84 FR 32993, July 11, 2019, unless otherwise noted.