Influence of Chemical Straightening on the Stability of Drugs of Abuse in Hair

This study investigated the impact of chemical hair straightening on the stability of drugs of abuse in hair. Using 'Lye' and 'No-Lye' relaxers, the researchers treated drug-fortified hair and hair from known drug users. They found that drug concentrations significantly decreased (P < 0.05) after treatment, with only 6-67% of the original concentration remaining in standard reference materials and 5-30% in authentic drug user hair. This indicated that chemical straightening substantially reduced detectable drug levels in hair samples.