"According to a European study, the prevalence in the Netherlands of the use of alcohol by car drivers is 2.2%, compared to 3.5% average in Europe. The use of cannabis by car drivers (1.7%) is above the European average of 1.3% (SWOV factsheet 2011). According to the Road Traffic Act it is forbidden to drive under the influence of a (illegal) substance affecting one's driving ability. The Ministers of Security and Justice and Transport are preparing a bill to change this Act in order to be better able to detect these drivers. Part of the bill is to give police investigators the authority to use an oral fluid screener as pre-selection method to detect drug use of traffic participants. The legal evidence will remain a blood test. The use of GHB is only detectable with a blood test. Like with driving under the influence of alcohol, threshold values will be defined for driving under the influence of drugs (e.g. 50 microgram per litre for amphetamine and cocaine and 3 microgram per litre for THC). A special commission has proposed limiting blood values per drug in accordance with international practices. Because some substances are occurring in the body and measuring instruments are not sensitive enough, zero limits are not feasible. The present bill uses behaviour-related limits, meaning that a limit is set above which driving skills are affected. There are fewer traffic casualties due to the use of drugs and medicines than to alcohol consumption (T.K. 29398-236; T.K. 32859-3; TK32859-7)."

Source

Van Laar, M.W., Cruts, A.A.N., Van Ooyen-Houben, M.M.J., Van Gageldonk, A., Croes, E.A., Meijer, R.F., et al. (2013). The Netherlands drug situation 2012: report to the EMCDDA by the Reitox National Focal Point. Trimbos-instituut/WODC, Utrecht/Den Haag, p. 19.
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