Amphetamines in washed hair of demonstrated users and workplace subjects.

In a study of volunteer subjects from drug rehabilitation programs, methamphetamine and amphetamine levels were determined in the hair of 40 subjects who had produced MS-confirmed methamphetamine-positive urine results. The samples were tested by radioimmunoassay and analyzed by LC/MS/MS after being washed with the 3.75-h wash procedure developed by this laboratory. In addition, results of non-user and workplace samples are presented. In workplace samples, levels of methamphetamine, amphetamine, methylenedioxy-methamphetamine (MDMA), and methylenedioxyamphetamine (MDA), are reported. The range of methamphetamine levels in the clinical samples (170-34,400 pg/mg hair) was not different from the workplace population (from less than the cutoff of 500 pg/mg to >20,000 pg/mg hair), but the workplace population had a lower percentage of high levels of drug. Amphetamine levels were found to vary widely in both populations, at all levels of methamphetamine. In the clinical population, no samples were positive for MDMA; in MDMA-positive workplace samples, the levels ranged from below the cutoff of 500 to >20,000 pg/mg, with MDA levels varying widely, similar to amphetamine levels in methamphetamine-positive samples.