Chloracne is an acneiform eruption of blackheads, cysts, and pustules associated with exposure to certain halogenated aromatic compounds, such as chlorinated dioxins and dibenzofurans.

The condition was first described in German industrial workers in 1897 by Siegfried Bettmann,[2] and was initially believed to be caused by exposure to chlorine (hence the name "chloracne").

It is believed, at least from rodent models, that the toxin activates a series of receptors promoting macrophage proliferation, inducing neutrophilia and leading to a generalised inflammatory response in the skin.

The inflammatory processes lead to the formation of keratinous plugs in skin pores, forming yellowish cysts and dark pustules.

The skin lesions occur mainly in the face, but in more severe cases they involve the shoulders and chest, the back, and the abdomen.