Code of Federal Regulations Title 21. Food and Drugs § 21.358.703 Definitions

(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.