Concordance between self-reported drug use and findings in hair about cocaine and heroin.

We have presented the results concerning 135 judicial expert opinion over a 3-year period. We have compared the measured levels in hair of 6-acetylmorphine (6-AM) and of cocaine with the habitual use declared by the consumers. This allows us to propose three levels (low, medium, high) of consumption in relation to the level of the 6-AM marker found in hair for the consumption of heroin, and the level of cocaine as a marker for the cocaine intake.