[Occupational dermatitis due to inhalation and ingestion]

Occupational materials contacted systemically, either by inhalation or ingestion, are capable of producing toxic as well as allergic skin reactions in exposed persons. Depigmentations of vitiligo type due to paratertiary butyl-phenol, various exanthems due to trichlorethylene fumes in the metal industry and due to alpha-phenylindole in the plastics industry, and the so-called vinyl chloride sickness in the PVC industry are examples of conditions with a probable toxic pathogenesis. Allergic skin conditions may occur as either immediate type (urticaria and Quincke's edema) or delayed type (endogenic contact eczema, more rarely pigmented purpuric eruptions) reactions. Relevant examples from the literature and our own case histories are briefly presented. Some types of eczema and dysidrosiform eruptions, which show an immediate type sensitization to occupational allergens of a protein nature in the skin tests, are difficult to interpret pathogenically. The prototype of such reactions is bakers' eczema with cutaneous vascular sensitization to flour. In addition, farmers' eczema can be related to an immediate type sensitivity to animal hair, resp. farm dust. Our own observations concerning such cases are briefly described.