[Allergic contact eczema caused by an acetone-formaldehyde condensate in billboard workers].

We report two cases of occupational contact dermatitis in billboard workers due to employment of a new paste additive. Clinical picture, patch test result, histological pattern of the test reaction and course of the disease indicate that the observed eczema are manifestations of contact allergy and do not represent irritant-toxic dermatitis. The glue is a hydrous solution of a heterogeneous mixture of condensation products of acetone and formaldehyde with a small part of free acetone and formaldehyde. Exact determination of the allergen and identification of the substance group failed. The allergen seems to be a strong sensitizer.