The final report on studies to identify possible etiological agents in byssinosis is presented. Reprints of all papers originating from the project are provided. The effects of a crude aqueous cotton bract extract (CBE) on the isolated trachealis muscle from dogs, guinea-pigs, and cats were evaluated. The CBEs induced contractions in the trachealis muscle. The active agents in the CBE were dialyzable, having molecular weights of less than 14,000. In studies of the effects of CBEs on pulmonary surface tension, ammonia removed about 90 percent of the surface active material from cotton dusts. Gossypol, a cotton metabolite, was found to be the agent probably responsible for most of the surface activity of cotton dusts. Studies with gossypol and other cotton metabolites, such as rutin and catechin, found they could compromise alveolar macrophage function, gossypol having the greatest effect and catechin the least. Studies on the effect of dimethyl-sulfoxide, acetone, ethanol, methanol, and ethyl-acetate on rabbit lung microsomal benzo(a)pyrene-hydroxylase activity were conducted to find the best solvent for pulmonary metabolism studies. Dimethyl-sulfoxide was the best solvent, and is recommended as the solvent vehicle of choice for pulmonary metabolism studies.
NIOSH, U.S. Department of Health and Human Services, Morgantown, West Virginia, 158 pages, 152 references