1. Detection of clostebol in sports: Accidental doping?
- Author
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Francesco Molaioni, Francesco Botrè, Michele Iannone, Daniel Jardines, Xavier de la Torre, and Cristiana Colamonici
- Subjects
Male ,Skin Absorption ,Metabolite ,Skin Cream ,Pharmaceutical Science ,Physiology ,Administration, Cutaneous ,01 natural sciences ,Analytical Chemistry ,03 medical and health sciences ,chemistry.chemical_compound ,Anabolic Agents ,0302 clinical medicine ,CLOSTEBOL ACETATE ,Humans ,Environmental Chemistry ,Medicine ,Testosterone ,030216 legal & forensic medicine ,Spectroscopy ,Doping in Sports ,business.industry ,010401 analytical chemistry ,Clostebol ,Neomycin ,Mass spectrometric ,0104 chemical sciences ,Drug Combinations ,Italy ,chemistry ,Female ,Physiological fluid ,business ,medicine.drug - Abstract
The detection of clostebol misuse in sports has been growing recently, especially in Italy, due to the ample availability of pharmaceutical formulations containing clostebol acetate (Trofodermin®) and the use of more sensitive instrumentation by the antidoping laboratories. Most of these cases have been claimed to be related to a nonconscious use of the drug or through contact with relatives or teammates using it. We have investigated, through the application of the well-known and currently used gas chromatographic mass spectrometric procedures, the likelihood of these allegations and have demonstrated that after a single transdermal administration of 5 mg of clostebol acetate and a transient contact with the application area, it is possible to generate adverse analytical findings in antidoping controls. We have reviewed the Phase I and Phase II clostebol metabolism in order to generate evidences that may help the sport authorities reviewing these cases. The main clostebol metabolite (4-chloro-androst-4-en-3α-ol-17-one, M1) generally used at the screening level as well as other three metabolites (M2-M4) are mainly excreted as glucuronides, whereas M5 (4ζ-chloro-5ζ-androstan-3β-ol-17-one) is predominantly excreted as sulfate. Neither the 5α-reductases activity (impaired by the presence of the chlorine in C4) nor specific sulfotransferases present in the skin allowed a clear distinction of the administration route. Studies with a larger number of volunteers and probably investigating another physiological fluid allowed in antidoping such as blood are needed for a deeper investigation. It is not unreasonable to establish a reporting level for M1, maybe creating some false negatives but excluding nonintentional doping scenarios.
- Published
- 2020