Byssinosis. Inhalation challenge with polyphenol.

Most studies designed to determine the etiologic agent in byssinosis have relied on in vitro test for normal volunteers to assess the effects of components isolated from cotton plants, cotton factory dust, or their associated organisms. In one of the few studies directly on byssinotic subjects, symptoms were reproduced on inhalation challenge with a condensed polyphenol isolated from bracts of cotton plants. The results were highly significant, with only byssinotic workers responding; however, when we repeated the investigation with 29 subjects, no individual responded to challenge with symptoms such as those experienced returning to work at the cotton mill after a weekend break. Tests of pulmonary function could not detect differences between polyphenol and saline challenges. Compared with groups of workers not exposed to cotton dust and matched for age and smoking habits, significant differences in pulmonary function were observed, confirming the detrimental effects of long-term exposure to cotton dust, particularly in combination with cigarette smoke.