Citation

Drasch G, von Meyer L, Roider G, Staack RF, Paul LD, Eisenmenger W. Blutalkohol 2006; 43(6): 441-450.

Affiliation

Institut fur Rechtsmedizin, Ludwig-Maximilians-Universitat Munchen, 80337 Munchen, Germany

Copyright

(Copyright © 2006, International Committee on Alcohol, Drugs and Traffic Safety and Bund gegen Alkohol und Drogen im Straßenverkehr, Publisher Steintor Verlag)

DOI

unavailable

PMID

unavailable

Abstract

Out of 6,525 drivers, who at a police check admitted to being solely impaired by cannabis, 135 were selected. These people had been legally convicted because of accidents or genuine endangering of road traffic through cannabis use. The selection of these cases could not be complete, but it was representative. The selected "accident-group" did not differ from the remaining 6390 cases, neither in the THC concentration in serum (accident-group: median 3.43 ng/ml; control-group: 3.71 ng/ml), nor in the THC-COOH concentration (34.5 vs. 35.3). 8.1 % of the accidents/cases of endangering of road traffic happened below THC concentrations of 1 ng/ml, 31.4% below 2 ng/ml. The opinions of the German Bundesverfassungsgericht (Federal Constitutional Court) (1 BvR 2652/03) and the Bayrischen Verwaltungsgerichtshof (Bavarian Administration Court) ( 11 CS 05.1711 ) that there is no real endangering of road traffic at THC concentrations below 1 and 2 ng/ml respectively, therefore cannot be supported. It was proven that in the late phase of the effect of cannabis the frequency of accidents and the endangering of road traffic is higher than during the acute inebriated phase. Not until THC-COOH drops below 10 ng/ml, accidents and cases of endangering become less frequent. This study will not provide an indication that the actual LOD for THC in serum (0.5 ng/ml) is the lower threshold limit for an adverse effect of cannabis on road traffic. Discrepancies between studies on real driving under the influence of cannabis and experimental studies may be explained to some extent by the fact that in reality the adverse effects of cannabis on road traffic are stronger in the late phase of action than in the acute inebriated phase. However, most experimental studies have been limited to the first few hours after the cannabis consumption and, therefore, have not collected data in the more dangerous late phase of action.

Keywords: Cannabis impaired driving

Language: de