Phototoxic and contact toxic reactions of the exocarp of sweet oranges: a common cause of cheilitis?

Irritant skin reactions were produced within 1 h after application of the exocarp of sweet oranges or alcoholic extracts therefrom. Such reactions faded within 48 h. The exocarp, or extracts thereof, induced phototoxic reactions which were strongest at 72 h after exposure. The phototoxic reactions were only induced in natural blondes and only with some oranges. The in vivo phototoxic reactions were confirmed in vitro, causing a slight but clear photo-inhibition of Candida albicans. Only some oranges inhibited growth.