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any racial bias in hair testing? (5) What is the influence of cosmetic treat-
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ments? Several answers were recently provided on these specific topics.
It is always possible to obtain a fresh identical hair sample if there is any
claim of a specimen mix-up or breach in the chain of custody. This makes
hair analysis essentially fail-safe, in contrast to urine analysis, since an iden-
tical urine specimen cannot be obtained at a later date. Clearly, hair analysis
can thus function as a “safety net” for urine analysis.
Unfortunately, according to the International Olympic Committee
(IOC), basic scientific knowledge in hair biology is still lacking to make scalp
hair analysis now a valid specimen in the field of doping control and the
following points should be resolved before applications: (1) analytical meth-
ods are missing for several doping compounds, such as diuretics, (2) peptide
hormones are not extractable, (3) hair washing, discoloring, tinting, and
hair color (resulting in potential ethnic discrimination) appear to influence
the concentration of drug measured in hair, and (4) drug incorporation
within the hair longitudinal axis and upon time is not proved to be regular
on all occasions.

3.5 Conclusions

It appears that the value of hair analysis for the identification of drug users
is steadily gaining recognition. This can be seen from its growing use in
preemployment screening, in forensic sciences, and in clinical applications.
Hair analysis may be a useful adjunct to conventional drug testing in doping
control. Specimens can be more easily obtained with less embarrassment,
and hair can provide a more accurate history of drug use.
Although there are still controversies on how to interpret the results,
particularly concerning external contamination, cosmetic treatments, ethnic
bias, or drug incorporation, pure analytical work in hair analysis has reached
a sort of plateau, having solved almost all the analytical problems.
Though GC/MS is the method of choice in practice, GC/MS/MS or
LC/MS are today used in several laboratories, even for routine cases, partic-
ularly to target low dosage compounds like corticoids.
In the case of doping control, drugs are screened in urine specimens
according to validated standard operating procedures in accredited labora-
tories. As forensic laboratories can be involved in testimony dealing with
doping agents, the idea of using hair for doping control has emerged as hair
analysis has been accepted in court in other cases. Courts can request addi-
tional information on the pattern of use of doping substances, such as during
the 1998 cycling Tour de France where blood, urine, and hair were simulta-
neously collected. Hair can both confirm repetitive abuse and identify the

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