The first method involves extensive chemical washing of the hair specimen prior to screening, followed by analysis of the content of the wash data. The second procedure focuses on the measurement of any metabolites that may be present. These unique metabolites are not present in the environment and their detection indicates that the individual has ingested drugs. Extensive independent studies confirm that external exposure is not a factor in Psychemedics hair testing results. In fact, normal hair washing helps to remove the external presence of drugs on the hair.
Drug residues remain permanently entrapped in the hair.
In fact, Psychemedics patented procedures routinely separate melanin, the color component of hair from the sample. Therefore, the hair tested is colorless.