Enhancement of comedogenic substances by ultraviolet radiation

Br J Dermatol. 1978 Feb;98(2):145-50. doi: 10.1111/j.1365-2133.1978.tb01615.x.


Ultraviolet radiation enhanced the capacity of human sebum, sulphur, cocoa butter, squalene, and coal tar to produce comedones in the external ear canals of rabbits. An enhancement of the comedogenicity of coal tar and squalene was similarly demonstrated in man. We conjecture that in occasional patients sunbathing may aggravate acne by augmenting the comedogenicity of sebum.

MeSH terms

  • Acne Vulgaris / chemically induced*
  • Adult
  • Animals
  • Cacao / adverse effects
  • Coal Tar / adverse effects
  • Drug Synergism
  • Ear, External
  • Humans
  • Male
  • Rabbits
  • Sebum
  • Squalene / adverse effects
  • Sulfur / adverse effects
  • Sunscreening Agents / adverse effects
  • Ultraviolet Rays / adverse effects*


  • Sunscreening Agents
  • Sulfur
  • Squalene
  • Coal Tar