Variability of opiates concentrations in human hair according to their anatomical origin: head, axillary and pubic regions.

The concentrations of morphine and codeine were investigated in hair from the head, axillary and pubic regions obtained from 20 fatal heroin cases. Hair preparation involves decontamination procedure in dichloromethane at 37 degrees C for 15 min, solubilization in sodium hydroxide at 100 degrees C for 5 min, neutralization with hydrochloric acid and centrifugation. After extraction in chloroform/isopropanol/n-heptane (50:17:33; v/v) at pH 9.2, drugs were derivatized with BSTFA + 1% TMCS and separated on a 12-m BP-5 capillary column. Quantification was done by GC/MS using selected ion monitoring. The highest morphine concentrations were found in public hair (0.80-41.34 ng/mg), followed by hair of the head (0.62-27.10 ng/mg), and axillary hair (0.40-24.20 ng/mg). Codeine was also detected in all samples, and the codeine/morphine ratios ranged from 0.54 to 0.273. The differences observed in drug concentration in the three kinds of hair are discussed in the light of the existing literature.