Analytical evaluation of a rapid on-site oral fluid drug test

There is a need for a reliable rapid on-site oral fluid test that can be used in police controls to detect impaired drivers. We evaluated the Varian OralabA (R) 6 and collected two oral fluid samples from 250 subjects, one with the Varian OralabA (R) 6 and one with the StatSure (TM) SalivaaEuro cent Sampler (TM). The OralabA (R) 6 can detect six drug types: amphetamines, methamphetamine, cocaine, opiates, delta9-tetrahydrocannabinol (THC), and phencyclidine (PCP). On-site results were obtained within 10 to 15 min. The sample collected with StatSure (TM) was analyzed using liquid chromatography-tandem mass spectrometry after liquid-liquid extraction and these results were used as a reference to determine prevalence, sensitivity, and specificity. Two cut-off values were used in the evaluation. The Varian cut-off values were: amphetamine 50 ng/mL, cocaine 20 ng/mL, opiates 40 ng/mL, and THC 50 ng/mL. The DRUID cut-offs were: amphetamine 25 ng/mL, cocaine 20 ng/mL, opiates 20 ng/mL, and THC 1 ng/mL. Applying the first cut-offs, prevalence, sensitivity, and specificity were: amphetamine 10%, 76%, 100%; cocaine 23%, 34%, 100%; opiates 38%, 83%, 94%; and THC 18%, 41%, 99%. The DRUID cut-off values gave the following results: amphetamine 14%, 56%, 100%; cocaine 28%, 34%, 100%; opiates 49%, 68%, 98%, and THC 45%, 16%, 99%. The specificity of the OralabA (R) 6 is generally good. For both cut-offs, sensitivity was low for cocaine and THC. Therefore, the Varian OralabA (R) 6 test is not sensitive enough to be applied during roadside police controls.