Formation of polychlorinated dibenzo-p-dioxins upon combustion of commercial textile products containing 2,4,4'-trichloro-2'-hydroxydiphenyl ether (Irgasan DP300).

Commercial textile products containing 2,4,4'-trichloro-2'-hydroxydiphenyl ether (Irgasan DP300) as an antimicrobial agent gave dichlorodibenzo-p-dioxin(s) (di-CDD) upon combustion. The extent of conversion of Irgasan DP300 into di-CDD(s) reached 19-43% at 600 degrees C. Upon bleaching the textile products with sodium hypochlorite, Irgasan DP300 was chlorinated to 2',3,4,4'-tetrachloro-2-hydroxydiphenyl ether, 2',4,4',5-tetrachloro-2-hydroxydiphenyl ether and 2',3,4,4',5-pentachloro-2-hydroxydiphenyl ether. These chlorinated derivatives were converted into trichlorodibenzo-p-dioxins and tetrachlorodibenzo-p-dioxin upon combustion, which are more toxic than di-CDD(s). These results suggest that the bleaching and incineration of textile products containing Irgasan DP300 result in environmental pollution by PCDDs.