Citation

Lechowicz W, Adamowicz P, Bakalarz D, Gil D, Skulska A, Tokarczyk B, Gieroń J. Prob. Forensic Sci. 2017; 110: 97-109.

Vernacular Title

Szacowanie zmian stȩżenia thc we krwi kierowców w czasie pomiȩdzy zatrzymaniem a pobraniem krwi do badań

Copyright

(Copyright © 2017, Institute of Forensic Research Publishers)

DOI

unavailable

PMID

unavailable

Abstract

it is difficult to assess the effect of substances acting similarly to alcohol on the psychomotor efficiency of a driver in cases of substances that are rapidly distributed to organs of the body, quickly metabolized or spontaneously decomposed under the influ- ence of the environment in which they are located. Such process can play a role in situations where it is necessary to interpret the result of a test on a blood sample collected a long time after a driver has been stopped. Among such compounds is ∆9-tetrahydro- cannabinol (THC) - a psychoactive hallucinogenic component of popular cannabis products known as marijuana and hashish.

As transpires from an analysis of data from blood collection protocols and test requests in Poland, the mean period of time be- tween a driver being stopped for a routine roadside control and blood collection was 2 hours and 40 minutes (median: 2 hours 20 min), and in the case of a road incident, this period was exactly 3 hours (median: 2 hours 50 min). Among 60 recorded cases, it was never shorter than 1 hour. For 27 drivers, for whom blood was collected two or three times at 1 hour intervals, it was shown that only for concentrations of THC in whole blood above 2 ng/ml was a significant drop in its concentration observed (over 0.13 ng/ml) in the course of one hour. This conclusion is particularly important when interpreting concentrations of THC within the range of concentrations (1-2.5 ng/ml) proposed by forensic toxicologists as thresholds for penalization for driving a vehicle under the influence of THC in Poland.

Key words
THC; elimination; Blood; Drivers; interpretation; cannabis impaired driving

Language: en