The Hague, The Netherlands: The use of cannabis and other psychoactive substances is not associated with an increase in the severity of car-crash related injury, according to data published in the current issue of the journal Traffic Injury Prevention.
Investigators at the Netherlands Forensic Institute and Utrecht University assessed the relationship between substance use and injury severity in a group of crash-involved drivers admitted to a regional trauma center. Authors determined that drivers who tested positive for the presence of drugs or alcohol in their blood or drug metabolites in their urine were no more likely to suffer from more severe injuries than were drivers who tested negative for the presence of psychoactive substances.
Authors wrote: “There is much evidence that driving under the influence of alcohol and/or drugs of abuse is related to an increased accident risk. A remaining question is whether the use of psychoactive substances is also related to clinically more sever accidents.”
They concluded, “[W]e found no relation between the use of psychoactive substances (alcohol, drugs) and the severity of injury. … More research is needed and blood sampling of all crash-involved drivers [to more accurately determine recent substance use] is recommended to confirm the[se] results and to [better] study the relation between the different classes of drugs and injury severity.”
Previous studies of on road accident data have indicated that recent use of cannabis, as determined by the presence of significant levels of THC in the blood, is associated with an elevated risk of accident compared to drivers who test negative for the presence of THC.
By contrast, motorists who test positive for the presence of THC metabolites in their urine – indicating their past use of cannabis at some unspecified point in time – do not appear to have an elevated accident risk compared to other drivers.
For more information, please contact Paul Armentano, NORML Deputy Director, at: paul@norml.org. Full text of the study, “The relation between the use of psychoactive substances and the severity of the injury in a group of crash-involved drivers admitted to a regional trauma center,” appears in the journal Traffic Injury Prevention. Additional information regarding marijuana use and on-road accident risk is available in the NORML report “Cannabis and Driving: A Scientific and Rational Review,” available online at: http://www.norml.org/index.cfm?Group_ID=7459.