One in five designated drivers really needs to have someone else driving the car.
A new study in the Journal of Studies on Alcohol and Drugs has found that 35 percent of designated drivers had consumed some amount of alcohol prior to getting behind the wheel. What’s more, most had blood-alcohol levels that were high enough to impair their driving.
There’s plenty of research showing that just a small amount of alcohol can significantly increase the potential for impairment. One drink can lead to a BAC of 0.029 in a 150-pound male, says Loyola University Maryland. Two drinks result in a BAC of 0.058 and three in a BAC of 0.087, over the legal limit in the U.S.. Notably, just one drink is enough to raise BAC to illegal levels in other countries.
A 150-pound-woman’s BAC rises at even higher rates from the same amount of alcohol, to 0.034, 0.068 and 0.101 after one, two and three drinks.
Study Finds That Many Designated Drivers Have Been Drinking
Adam Barry, an assistant professor of health education and behavior at the University of Florida in Gainesville studied 1,071 bar patrons (most of whom were white male college students) over a 3-month period in the “downtown restaurant and bar district of a major university town in the Southeast”; 165 were designated drivers. The researchers interviewed participants about demographic data and alcohol-related behaviors and then tested their BAC with a hand-held breath-testing instrument.
While the non-driving participants’ BAC was higher than those of the designated drivers, 35 percent of the 165 self-identified designated drivers had consumed alcohol. 17 percent had BACs of between 0.02 and 0.049 percent; 18 percent had BACs of 0.05 percent or higher.
Barry and the other researchers also administered an Alcohol Use Disorders Identification Test-consumption (AUDIT), a ten-question test meant to determine if someone’s alcohol consumption is harmful. The psychomotor functions and driving abilities of the designated drivers whose BAC was 0.05 or higher were indeed affected.
Why Would a Designated Driver Risk Everyone’s Life?
Group dynamics can certainly play a part in a designated driver drinking, say the researchers. In addition, the other passengers may well be ”loud, or start roughhousing” and distract a driver. Along with “the fact that most people drink at night, when any driver’s vision is diminished … you have a potential recipe for disaster,” Barry emphasizes.
“If you look at how people choose their designated drivers, oftentimes they’re chosen by who is least drunk or who has successfully driven intoxicated in the past — successful meaning got home in one piece … that’s disconcerting,” as Barry says. While people may figure that “as long as they don’t feel drunk they are all right to drive,” your driving skills are affected before you sense the “buzz” that signals intoxication.
In other words, we shouldn’t wonder how much alcohol can impair our thinking and driving skills. The fact is that any amount can and does. A fun summer’s night out with friends should never end, as it too often has, in tragedy.
BAC in U.S. Higher Than in Other Developed Nations
In the U.S., the legal limit for driving is a blood-alcohol concentration (BAC) of 0.08. That’s one of the highest allowable legal limit of any developed country: Japan has a zero percent tolerance. Russia and Sweden have a level of o.02 and Denmark, Finland and Greece are among the more than 100 countries that use the 0.05 level.
No wonder that, back in May, federal accident investigators recommended that the drunk driving limit be lowered from 0.08 to 0.05 in the U.S.
About 30 percent of vehicle fatalities are connected to drunken driving. Barry’s and his colleagues’ study adds further evidence to why the allowable BAC level in the U.S. should be lowered, as well as offering a harsh reminder of why drinking and driving go together like oil and water.
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