[Allergy and professional exposure to sulfur compounds: questions posed]

We present here four cases of respiratory diseases which may be due to the exposition or to the handling of sulfur derivatives due to their professional activity. The responsibility of these compounds stands on the clinical history, biological cellular tests and for one of them on the evolution under a metabisulfite-free diet and a positive oral provocation test at 5 mg. The present economical crisis makes the patient-clinician relationship difficult, due to patients' wishing to hide their pathologies or their professional activities.