Hair Analysis and Doping Control

Abstract

Hair analysis has been used in forensic toxicology for about 50 years. In the anti-doping laboratories accredited by the World Anti-Doping Agency (WADA), the matrices usually used are urine and blood. In a case of an adverse result, it is up to the athlete to prove their innocence. The athlete can therefore request additional and alternative analyses such as hair analysis. Hair has many advantages, such as the possibility to establish a consumption profile or differentiate a single dose from repeated consumption. Nevertheless, it has some limitations such as poor incorporation of acidic and neutral molecules, and the impossibility to discriminate exposure routes. The limitations and the advantages of hair should be taken into consideration when interpreting the results. In some cases, a hair test can document dietary or environmental contamination. To date, at least one prohibited molecule per class from the WADA list has been detected in hair, except for peptide hormones. However, although there are many data available for common drugs of abuse, controlled studies are lacking for some classes such as anabolic steroids. Given the benefits offered by hair but also the known limitations, this analysis should be considered as a complement and not an alternative, as stated in the WADA regulations.