Under conditions of the channel black technique of the carbon black producing factory in Oranienburg, DDR, some inhalative noxious agents are discussed, especially dust of carbon black in concentrations three times higher than permitted and the climate is causing aggravated conditions. 58 still exposed, 35 formerly exposed workers and 60 control persons of the same age and smoking habits were asked using a questionnaire and they were examined clinically to find out disturbances of health in the upper airways. Complaints concerning chronic rhinitis partly complicated by crusts and sanguineous nasal secretion more frequently had been stated by exposed workers compared to the control persons. The rhinoscopical findings of the exposed workers and control persons are emphasizing the case history details. By it, more severe chronical mucosal findings were diagnosed in 29 percent of the exposed, but only in 9 percent of the control persons. Obstructions of the nasal breathing are not to be related to the profession in spite of the significant differences of the anamnestical data and clinical findings. On the contrary the disorders of smell seem to be more important concerning the soot exposed workers. The roentgenological findings of the paranasal sinus and the cytological results of nasal secretion do'nt give further hints. The importance of an exposition of more than 10 years is apparent concerning the described morbid changes. Significant fewer complaints concerning the ENT were stated by the formerly exposed workers than the still exposed. Special examinations by an ENT physician should be performed on workers exposed to carbon black having already longer persistent complaints particularly concerning chronical mucosal findings and disorders of smell.