Dust exposure and health complaints were recorded by means of personal samplers and a questionnaire for potroom workers in a primary aluminum plant situated at the west coast of Norway. The study revealed a higher dust exposure and a higher prevalence of acute health complaints during a period when fluoride recovery alumina from a dry-cleaning process was used compared to another period when pure alumina was used. Weather conditions and work conditions were otherwise similar during the two periods. This finding indicates that the use of recovery alumina increases the pollution of the work atmosphere and thereby causes more health complaints. The study also revealed a higher prevalence of pulmonary symptoms of a chronic recurrent nature than expected, in spite of the thorough selection which takes place before and during employment, and may therefore indicate that potroom workers are under the risk of developing chronic pulmonary disease.