Prevalences of obstructive airway diseases, i.e. of bronchial asthma and COPD, are in the range of 5% in our populations. Approximately every 10th of these cases is caused by occupational agents. Due to different pathomechanisms and legal definitions allergic disorders have to be separated from irritant disorders. A further entity represents isocyanate induced diseases (caused by hardeners, agents for manufacturing of plastics etc.). The latter mainly behave as irritants but may also elicit allergic reactions. Among causative occupational allergens flour, food and feed products and latex dominate; among irritative agents hairdresser material, welding and cutting fumes and varnishes are most important. In most cases prognosis is poor; it depends on duration of exposure to causative agents. This emphasizes the need of early diagnosis and individual preventive measures.
