Search

A rapid, sensitive and specific procedure is described for the mass screening and confirmation of barbiturates in urine specimens. The method is sensitive to 0.5 mug/ml levels of the commonly used barbiturates. The urine samples are screened by radioimmuno-assay. Specimens screened positive are confirmed by gas-liquid chromatography using a flame ionization detector. The barbiturates are analyzed as free acids on a 10% UC W-98 column and as their dimethyl derivatives on a 3% OV-17 column. This dual approach eliminates false positives caused by interfering substances which may be present in the urine, thus resulting in a method specific for the barbiturates.

Concerning drugs in general, proficiency testing has undoubtedly been a major contributing factor to improved detection. Some of the improvement may be due to advances in technology, and this is possibly the case with improvement in the detection of morphine and methadone. The improvement in the determination of methamphetamine within three surveys over six months can clearly be attributed to proficiency testing. In drug screening for cocaine abuse, the poor results in proficiency testing for the detection of the primary metabolite, benzoylecgonine, has clearly demonstrated that laboratories are not proficient in this screening.

Laboratory evaluation of illicit drug abuse was conducted in a major correctional institution. Fifty-eight prison inmates were screened for common drugs of abuse in conjunction with a triazolo-benzodiazipine compound tolerance protocol. Urine specimens were collected on days -1, 1, 15, 29, and 49 and assayed for amphetamines, opiates, barbiturates, and alcohol. Quinine was detected in two individuals and was probably derived from cold remedy preparations rather than the illegal use of heroin. While occasional illicit drugs may find their way into a prison population, this study showed no evidences of drug abuse in one correctional institution whose prisoners participated in Phase I drug evaluations.