Testing for Stanozolol, Using UPLC-MS-MS and Confirmation by UPLC-q-TOF-MS, in Hair Specimens Collected from Five...

An athlete challenged the result from an in-competition doping test which returned with an adverse analytical finding for stanozolol, claiming it was due to supplement contamination. Her lawyer asked the laboratory to analyze several hair specimens simultaneously collected from five different anatomical regions, head, arm, leg, pubis and armpit, to document the pattern of drug exposure. A specific UPLC-MS-MS method was developed. After decontamination with dichloromethane, stanozolol was extracted from hair in the presence of stanozolol-d3 used as internal standard, under alkaline conditions, with diethyl ether. Linearity was observed for concentrations ranging from 5 pg/mg to 10 ng/mg. The method has been validated according to linearity, precision and matrix effect. Concentrations of stanozolol in head hair, pubic hair, arm hair, leg hair and axillary hair were 73, 454, 238, 244 and 7,100 pg/mg, respectively. The concentration of stanozolol in head hair is in accordance with data published in the literature. When comparing the concentrations, body hair concentrations were higher than the concentration found in head hair. These results are consistent with a better incorporation rate of stanozolol in body hair when compared to head hair. The simultaneous positive concentrations in different hair types confirm the adverse analytical finding in urine of the top athlete, as the measured concentrations do not support the theory of contamination. For the first time, an anabolic agent was simultaneously tested in hair collected from five different anatomical regions from the same subject, with a large distribution of concentrations, due to anatomical variations, and these findings will help interpretation in further doping cases when documented with hair.