[Comparative evaluation of chemical methods for determining diethylstilbestrol in tissues of animal origin].

Three chemical methods for determination diethylstilbestrol (DES) in biological material (Jons and Deferage, 1953; Ponder, 1966; Official Method of Pharmacopoeia, USA, 1965) were compared. The most adequate method for determination of DES in animal tissue is the Official method of Pharmacopoeia based on a specific reaction. The method yields reproducible results. Average recovery of pure DES added to biological material was 78%. The method by Jons and Deferage though providing recovery of 86% of the added DES is based on nonspecific reaction with SbCl5, which resulted in too high results. Method of Pharmacopoeia (USA) was used to determine residual amounts of DES in tissues of a rabbit, implanted with 0.1 mg DES per 1 kg weight. One month after implantation, trace amounts of DES were detected only in muscle tissues. Two and three months after implantation, the residual amounts of DES in the rabbit tissues were not detected.