TY  - JOUR
PY  - 2013//
TI  - Influence of ethanol on the pharmacokinetic properties of Δ9-tetrahydrocannabinol in oral fluid
JO  - Journal of analytical toxicology
A1  - Toennes, Stefan W.
A1  - Schneider, Kirsten
A1  - Wunder, Cora
A1  - Kauert, Gerold F.
A1  - Moeller, Manfred R.
A1  - Theunissen, Eef L.
A1  - Ramaekers, Johannes Gerardus
SP  - 152
EP  - 158
VL  - 37
IS  - 3
N2  - Oral fluid (OF) tests aid in identifying drivers under the influence of drugs. In this study, 17 heavy cannabis users consumed alcohol to achieve steady blood alcohol concentrations of 0 to 0.7 g/L and smoked cannabis 3 h afterward. OF samples were obtained before and up to 4 h after smoking and on-site tests were performed (Dräger DrugTest 5000 and Securetec DrugWipe 5+).Maximum concentrations of tetrahydrocannabinol (THC) immediately after smoking (up to 44,412 ng/g) were below 4,300 (median 377) ng/g 1 h after smoking and less than 312 (median 88) ng/g 3 h later with 5 of 49 samples negative, suggesting that recent cannabis use might occasionally not be detectable. An influence of alcohol was not observed. Drinking 300 mL variably influenced THC concentrations (median only -29.6%), which suggests that drinking does not markedly affect on-site test performance. Many (92%) Dräger tests performed 4 h after smoking were still positive, indicating sufficient sensitivity for recent cannabis use. Differences in the results of a roadside study with DrugTest 5000 (sensitivity 84.8%, specificity 96.0%, accuracy 84.3%) could be explained by a higher number of true negatives, differences between OF and serum and differences between occasional and chronic users.    Keywords: Cannabis impaired driving  <p />  <p>Language: en</p>
LA  - en
SN  - 0146-4760
UR  - http://dx.doi.org/10.1093/jat/bkt002
ID  - ref1
ER  -