Amphetamine and N-Acetylamphetamine Incorporation into Hair: An Investigation of the Potential Role of Drug Basicity in Hair Color Bias

This study investigated the role of drug basicity in the incorporation of drugs into hair of different colors using Long-Evans rats. The researchers found that amphetamine, a basic drug, was incorporated more into black hair (6.44 +/- 1.31 ng/mg) than white hair (2.04 +/- 0.58 ng/mg). In contrast, the non-basic analogue N-acetylamphetamine (N-AcAp) showed no significant difference in incorporation between black (0.87 +/- 0.08 ng/mg) and white hair (0.83 +/- 0.15 ng/mg). This suggested that drug basicity played a role in the preferential incorporation of drugs into darker hair.