Detection of phencyclidine in hair.

Phencyclidine (PCP) can be detected in human hair wih commercially available radioimmunoassay regents. hair samples of all subjects admitting PCP use were positive, while thin-layer chromatographic urine analyses were positive in only one of seven cases. Presumably the drug is incorporated into the hair during periods of drug use and then retained in that particular section of the hair for its lifetime. Earlier results in this laboratory in a more detailed study of opiate retention in hair indicated not only that nanogram levels of the drug could be measured in a single strand of hair, but also that sectional analysis of the strand could indicate the time of drug use. The PCP results again suggest that the hair sample could serve as a valuable tool in the determination of drug abuse histories. The sample accessibility and stability and the long-term retention of the drugs in hair exemplify the potential advantages of the hair sample over the body fluid sample.