When we see the term DUI (Driving Under the Influence), we assume alcohol is the culprit. However, there is a growing body of evidence that the "influence" is drugs - whether illicit or over-the-counter.
A study completed in British Columbia recently revealed similar results to others conducted in Canada and the United States - a significant percentage of drivers have drugs in their system.
As part of the 2010 British Columbia Roadside Survey, The Canadian Centre on Substance Abuse (CCSA) asked 2,849 drivers in five B.C. cities to voluntarily provide breath and oral fluid samples to test for the presence of drugs or alcohol. More than 200 drivers, 7.2 per cent of the total number of drivers tested in the random survey, had detectable levels of drugs in their systems.
The report concluded that "driving after drug use is a growing issue that is as prevalent as driving after alcohol use - and that drug-impairment may also be a contributing factor to collisions and fatal road crashes."
By way of comparison. 9.9 per cent of the same group had detectable levels of alcohol in their blood. Cannabis and cocaine were the most common drugs. The report also discovered that "drug use among drivers is more evenly distributed than alcohol use when it comes to age group, time of day, and day of the week."
An earlier report from the CCSA reported that 33 per cent of drivers who died in vehicle crashes on public roadways in Canada between 2000 and 2007 tested positive for drugs. The National Highway Traffic Safety Administration in the United States says that in a multi-state study of fatal crashes, almost one in five drivers (18 per cent) had drugs other than alcohol in their bodies; prescription and illegal drugs were represented about equally. NHTSA says the most common drugs are cannabis, minor tranquilizers, stimulants and opiates.
Another study by the American Substance Abuse and Mental Health Services Administration (SAMHSA) showed that 16.6 per cent of American drivers over the age of 21 admitted driving while under the influence of alcohol or illicit drugs.
Extracted from data from the National Surveys on Drug Use and Health, 2002 and 2003, the SAMHSA report, Driving Under the Influence among Adult Drivers, estimated that among adult drivers ages 21 or older, 15.7 per cent drove under the influence of alcohol, 4.3 per cent drove under the influence of illicit drugs; and 3.0 per cent drove under the combined influence of alcohol and drugs, during the past year.
The report also found that the propensity to drive while under the influence of alcohol or drugs is lower for females and goes down with age. It indicates females over the age of 21 are half as likely to have done so and that overall 33.8 per cent of those between 21 and 25 had, 24.3 per cent of those in the 26-34 year range, 10 per cent in the 50-65 range and only 3.4 per cent of those over 65 years of age.
The authors of the British Columbia report says the total number and percentage of drivers using drugs may be higher than reported because some drug levels may have been below detection thresholds.
The British Columbia Automobile Association says a bigger problem is that the drugs are not being used in isolation. A second CCSA study, A Comparison of Drug and Alcohol-involved Motor Vehicle Driver Fatalities, reported that 33 per cent of drivers killed in accidents tested positive for drugs, compared to 37 per cent who were positive for alcohol.
Even over-the-counter non-prescription drugs, such as cold and flu remedies, travel sickness medication, pain relievers, eye drops, cough syrups, allergy medications, etc., may contain antihistamines, alcohol, codeine, and other compounds especially dangerous for drivers. Labels commonly state "may cause drowsiness," "do not operate machinery," Used in combination with alcohol or other drugs, the likelihood of impairment is greatly enhanced.
As jurisdictions around the world try to come to grips with the mounting societal costs of traffic injuries and fatalities, drugs are a raising a red flag.
Halifax-based Richard Russell runs a driving school.
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