Designated Drivers Not Always Sober
June 10, 2013

Study Finds Over A Third Of Designated Drivers Not Quite Sober

Brett Smith for - Your Universe Online

About 35 percent of designated drivers leave the bar with some alcohol in their bloodstream, according to a new study from the University of Florida. Of those found drinking in the study, about half had blood alcohol content (BAC) level above .05 — the threshold recommended by the National Transportation Safety Board (NTSB) in May.

"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," said Adam Barry, an assistant professor of health education and behavior at UF and co-author of a report on the study that recently appeared in the“¯Journal of Studies on Alcohol and Drugs.

To reach their findings, researchers approached patrons leaving bars between 10 p.m. and 2:30 a.m. over the course of six Friday nights before UF home football games in fall 2011. About 1,000 people, mostly Caucasian, agreed to be tested. The mean age of the volunteers was 28; 10 percent of those surveyed were Hispanic, 6 percent were Asian and 4 percent were African-American.

After a preliminary three- to five-minute survey, volunteers then had their blood-alcohol content tested with a hand-held breathalyzer.

While non-driving patrons had significantly higher BACs than the designated drivers, 35 percent of the self-identified designated drivers had been drinking. About half of those that tested positive for alcohol had a BAC of .05 percent or higher.

Last month, the NTSB voted to recommend that all 50 states enact a DUI cutoff of .05. The current standard is .08. Barry noted that the American Medical Association made the same recommendation of .05 almost 30 years ago.

The researchers theorized that social dynamics or a casual attitude about one or two drinks could be reasons why designated drivers often consume alcohol. Previous research has also suggested, however, that simply not designating a driver before drinking commenced could be why some get behind the wheel after a few drinks. Barry also noted the difficulty for people to accurately evaluate their own sobriety.

"That's the insidious nature of alcohol — when you feel buzzed, you're drunk," he said.

While American researchers tend to say drivers should completely abstain for alcohol, international researchers have concluded that a person can drink and drive if his or her blood-alcohol level remains below the legal limit.

However, that stipulation means different things in different countries. The United States has one of the highest legal limits of any developed country at .08. For Denmark, Finland and Greece .05 level is the legal limit. Both Russia and Sweden have a limit of .02, and in Japan drivers who test positive for alcohol at any level are considered to be driving while impaired.

According to the NTSB website, almost 10,000 Americans die in alcohol-related accidents each year. Another 170,000 are injured in alcohol-related incidents. The statistics show an improvement compared to 30 years ago, however, when about 20,000 died annually.