Out of 16 workers in a trout processing industry, ten experienced work-related cough, dyspnoea, and nasal secretion. A clinical examination was performed including specific IgE, precipitating antibodies IgG for trout and processing water, skin prick testing and peak flow monitoring. A total of four workers showed a positive allergic reaction. Processing water contained endotoxin and bacteria in high amounts. It is concluded, that work-related respiratory symptoms should be investigated and the cause at the workplace identified, so that preventive measures can be introduced.