---
kind: "section"
citation: "21 C.F.R. § 556.640"
title: "21"
number: "556.640"
heading: "Sulfadimethoxine."
url: "https://uscodex.org/cfr/21/556.640"
---

# §556.640. Sulfadimethoxine.

- (a) [Reserved]
- (b) **Tolerances.** The tolerances for sulfadimethoxine are:
  - (1) **Catfish and salmonids.** Edible tissues: 0.1 ppm.
  - (2) **Cattle.**
    - (i) **Edible tissues (excluding milk)—** 0.1 ppm.
    - (ii) **Milk—** 0.01 ppm.
  - (3) **Chickens, turkeys, ducks, and chukar partridges.** Edible tissues (excluding eggs): 0.1 ppm.
- (c) **Related conditions of use.** See §§ [520.2220a](/cfr/21/520.2220a.md), [520.2220d](/cfr/21/520.2220d.md), [520.2220e](/cfr/21/520.2220e.md), [522.2220](/cfr/21/522.2220.md), and [558.575](/cfr/21/558.575.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.