Suitability of SoToxa® Oral Fluid Screening Over Time: Re-Examination of Drugged Driving in Wisconsin.

Drug-impaired driver detection is a critical element of traffic safety. However, shifting drug use patterns over time and geography may limit the long-term reliability of assay-based screening tools. In this work, we compare qualitative results from the Abbott SoToxa® oral fluid (OF) screening device to Quantisal™ OF and whole blood. Our objective was to examine these three qualitative toxicological approaches, scope applicability of OF collection at the roadside, and compare them with a previous analysis of SoToxa® in Wisconsin. OF specimens were screened with the SoToxa® for six drugs or drug classes including amphetamine, benzodiazepines, cocaine, methamphetamine, opioids and tetrahydrocannabinol (THC). OF and blood specimens were collected from 106 participants. Quantisal™ OF and blood specimens were screened for drugs on ultra-performance liquid chromatography coupled to quadrupole time-of-flight high-resolution mass spectrometry (UPLC-QToF-HRMS) using a data-independent acquisition mode. UPLC-QToF-HRMS data were compared to comprehensive spectral libraries, and drugs were qualitatively identified. Drug Recognition Expert evaluations were performed, and face sheets submitted for 21 participants in this work. In general, the SoToxa® results were consistent with the combined qualitative results observed in Quantisal™ OF specimens and whole blood specimens. Limitations were uncovered for benzodiazepines, opioids and THC. The SoToxa® benzodiazepine assay has high cutoff concentrations for diazepam and clonazepam, limiting its sensitivity and positive predictive value when considering these drugs. SoToxa® opioid screening did not detect fentanyl, which is increasingly prevalent among drug users. Finally, ∆9-THC and its major metabolite 11-nor-9-carboxy-∆9-THC are lipophilic, limiting partitioning into OF. Despite these limitations, the SoToxa® instrument may be useful in assisting law enforcement with identifying individuals driving under the influence of drugs and establishing probable cause at roadside for making impaired driving arrests. Furthermore, Quantisal™ OF may be useful as screening specimens due to their ease of collection and results consistent with whole blood.

Drugged Driving in Wisconsin: Oral Fluid Versus Blood.

A pilot project was conducted in Dane County, Wisconsin, to evaluate the frequency of individuals driving under the influence of drugs (DUID). Evidentiary blood specimens, collected from subjects arrested for Operating While Intoxicated (OWI), were compared to oral fluid (OF) results obtained with the Alere DDS2®, a handheld screening device. The project objectives were to evaluate (i) the Alere DDS2® for use by police officers in the field, (ii) the frequency of individuals DUID and drugs combined with alcohol among OWI cases, (iii) the differences between detecting drugs in OF and in blood, and (iv) the effect of the laboratory drug testing cancellation policy (LCP) when the blood alcohol concentration (BAC) exceeds 0.100 g/100 mL. Following the arrest and collection of blood, subjects were asked to voluntarily participate in the project and provide an OF specimen. The OF was presumptively screened with the Alere DDS2® for six drug categories including (ng/mL) amphetamine (50), benzodiazepines (temazepam, 20), cocaine (benzoylecgonine, 30), methamphetamine (50), opioids (morphine, 40) and THC (delta-9-THC, 25). Results obtained with the OF screening instrument were not confirmed. A total of 104 subjects (22 female, 82 male), ages 18-72, were included in the project. Blood specimens were tested by gas chromatography-headspace (GCHS-FID) for volatiles, enzyme immunoassay (Siemens Viva-E Drug Testing System), and an alkaline basic drug screen with gas chromatography-mass spectrometry (GCMS) analysis. To compensate for differences between the EIA and the Alere DDS2® drug categories, results from the enzyme immunoassay and the alkaline basic drug screen were combined for purposes of comparing OF to blood. Seventy-six of 104 (73%) subjects arrested for OWI were driving under the influence of alcohol; 71 of the 76 had a BAC exceeding 0.10 g/100 mL. Subjects with a BAC exceeding the LCP, screened positive for drugs in both OF (n = 29) and blood (n = 28). Overall, one or more positive drug screening result was observed in 57 (55%) and 50 (48%) subjects for OF and blood specimens, respectively. THC was the most frequently detected drug category in both OF (n = 46) and whole blood (n = 44). Drug Recognition Expert (DRE) evaluations were performed on 18 subjects. In general, the Alere DDS2® results were consistent with the combined screening results observed in evidentiary blood specimens. This project was limited in scope as a second OF specimen was not collected for confirmation of drugs, however it did demonstrate that nearly 40% of the subjects with concentrations of alcohol exceeding 0.10 g/100 mL, screened positive for one or more drug categories in both OF and blood. The Alere DDS2® portable OF screening instrument may be useful in assisting law enforcement with identifying individuals driving under the influence of drugs and establishing probable cause at roadside for making DUID arrests.