AbstractGossypol has been identified as a component of bract (FDB) from frost‐killed, field‐grown cotton by its chromatographic behavior on films of silica and cellulose (four eluents and five methods of detection). In addition, a derivative of gossypol was detected, and it was shown chromatographically that gossypol was removed from extracts of FDB by a divalent metal and by aniline. The total gossypol content, by spectrophotometric determination of gossypol‐aniline complex, of FDB was 0.93%, but for a sample of bract from a cotton plant that had been grown in a hothouse it was only 0.048%. However the free gossypol contents in both were similar (0.065% and 0.044%, respectively). Both bract samples were from glanded cotton varieties. It is worthwhile to investigate the effect of gossypol on lung tissue to see if it can contribute to the acute response of byssinosis. In addition, it is noted that the waste from ginned cotton which is sometimes used as livestock feed may contain gossypol.