The authors describe a case of allergic contact eczema of the hands, forearms, face and thighs in a 28-year-old woman engaged in the production of insulin and heparin in a large pharmaceutical firm. The afflicted female was systematically in contact for 18 months with surface disinfectant based on aldehydes and quaternary ammonium compounds . Allergological examination revealed atopy restricted to a narrow spectrum of inhaled allergens, epicutaneous tests with glu- tar(di)aldehyde (0.25% aq.), benzalkonium chloride (0.1% vas.).were positive (2+), latex gloves negative, in standard and drug tests only an irrelevant reaction to merthiolate was found (1+). The prerequisite of proper examination and subsequent prevention is detailed knowledge of the composition and availability of different constituents of the composite disinfectant for the implementation of special epicutaneous tests. The authors discuss the occurrence and use of benzalkonium chloride incl. its presence in some drugs for external use.

        Key words: occupational contact eczema, cold disinfection, contact allergy, benzalkonium chloride, glutar(di)aldehyde