Phototoxic dermatitis caused by celery infected by Sclerotinia sclerotiorum

11 men developed a severe phototoxic dermatitis of the hands and forearms after harvesting celery infected with Sclerotinia sclerotiorum. By thin-layer chromatography and fluorescence spectrophotometry, xanthotoxin, bergapten and sphondin were isolated. The Canadida albicans test demonstrated xanthotoxin and bergapten as the phototoxic compounds.