Hair analysis for cocaine continues to be a valuable tool in forensic and clinical toxicology.

摘要

Recently, LeBeau and Montgomery (1) informed readers that the FBI Laboratory decided to suspend cocaine analysis in hair except children's hair. This decision was explained by newer research findings, according to which the criteria of the Substance Abuse and Mental Health Services Administration (SAMSHA) for a hair sample positive for cocaine (2) can also be met in contaminated hair specimen (3,4). These criteria, which are generally accepted for forensic purposes, consist of a cocaine concentration > 500 pg/mg and either a benzoylecgonine concentration > 50 pg/mg plus a benzoylecgonine-to-cocaine ratio > 0.05 or, alternatively, a concentration > 50 pg/mg of the non-hydrolytic cocaine metabolites norcocaine or cocaethylene. In principle, cocaethylene could be expected only if cocaine is consumed in combination with alcohol.