Driving under the influence of drugs (DUID) remains a subject of concern worldwide, and its increasing trend is likely to continue. Therefore, there is a constant need for reliable on-site drug tests to identify drugged drivers during roadside patrols. Performance and reliability of four on-site drug tests were evaluated among a high number of DUID cases in Germany. Results of oral fluid (OF) (RapidSTAT ® and DrugWipe ® 6S) and urine (DrugScreen ® 5TK and 7TR) test devices were compared with corresponding serum/plasma results obtained by confirmation analyses in consideration of recommended analytical limits for substances pertaining the annex of the German Road Traffic Code ('Straßenverkehrsgesetz', StVG) s. 24a (2). Overall, the screening devices performed well for individual drugs; however, none of the test devices assessed in this study fulfilled the ROSITA-1 criteria (sensitivity, specificity ≥ 90% and accuracy ≥ 95%) for all substances. Our data demonstrated that both urine tests showed high sensitivities for most compounds. DrugWipe ® 6S (94%) and RapidSTAT ® (93%) revealed high sensitivities, especially for amphetamine screening. Poor specificities (<90%) and accuracies (<95%) were observed for all tests except for low-prevalent substances (e.g., opiates). For drug testing in OF, Δ 9tetrahydrocannabinol (THC) still seems to be a compound of concern due to poor sensitivity (RapidSTAT ® , 77%; DrugWipe ® 6S, 85%), although the results indicate improvements compared with previously reported data. Although the obtained data indicate reliable detection for some substances, deployment of trained police officers is inevitable to identify DUID suspects by signs of recent use and recognising impairment.driving under the influence of drugs (DUID), oral fluid, roadside drug testing, serum/plasma, urine

This case report demonstrates the impact of different sampling sites on the quantification of narcotic substances. In 2020, officers secured a syringe containing a light-yellow paste-like substance, for which a drug pre-test indicated a positive result for amphetamine, inducing subsequent analyses of the sample by means of a gaschromatographic-mass spectrometric method (GC–MS) and liquid chromatography–(tandem) mass spectrometry (LC–MS/MS). Depending on the sample location, different results were obtained, with amphetamine not being detected in each sample. Amphetamine was particularly found at the outlet of the syringe, while amphetamine detection on the inside of the syringe at the plunger seal was only possible occasionally and, moreover, in lower concentrations. Based on this and with regard to the comparatively small amphetamine concentrations, contamination of the syringe (especially on the tip of the syringe) was assumed. Hence, the results strengthened the importance of the implication of different sampling sites, when either homogenization of the sample is not feasible or is not performed for reasons of plausibility checks concerning possible contamination of the sample.