---
kind: "section"
citation: "21 C.F.R. § 358.703"
title: "21"
number: "358.703"
heading: "Definitions."
url: "https://uscodex.org/cfr/21/358.703"
---

# §358.703. Definitions.


As used in this subpart:

- (a) **Coal tar.** The tar used for medicinal purposes that is obtained as a byproduct during the destructive distillation of bituminous coal at temperatures in the range of 900 °C to 1,100 °C. It may be further processed using either extraction with alcohol and suitable dispersing agents and maceration times or fractional distillation with or without the use of suitable organic solvents.
- (b) **Dandruff.** A condition involving an increased rate of shedding of dead epidermal cells of the scalp.
- (c) **Psoriasis.** A condition of the scalp or body characterized by irritation, itching, redness, and extreme excess shedding of dead epidermal cells.
- (d) **Seborrheic dermatitis.** A condition of the scalp or body characterized by irritation, itching, redness, and excess shedding of dead epidermal cells.
- (e) **Selenium sulfide, micronized.** Selenium sulfide that has been finely ground and that has a median particle size of approximately 5 micrometers (µm), with not more than 0.1 percent of the particles greater than 15 µm and not more than 0.1 percent of the particles less than 0.5 µm.

## Notes

### Amendments

[56 FR 63568, Dec. 4, 1991, as amended at 59 FR 4001, Jan. 28, 1994]

### Source

Source: 56 FR 63568, Dec. 4, 1991, unless otherwise noted.

### Authority

Authority: 21 U.S.C. 321, 351, 352, 353, 355, 360, 371.

### Source

Source: 55 FR 33255, Aug. 14, 1990, unless otherwise noted.

### Amendments

[56 FR 63568, Dec. 4, 1991, as amended at 59 FR 4001, Jan. 28, 1994]