TUESDAY, May 1 (HealthScout) -- States that slash legal blood alcohol levels for teen-agers have seen a dramatic drop in the number who say they would drink and drive, says the largest survey of its kind.
If teens are drinking, almost 20 percent of them say they won't drive; if they've had at least five drinks, another 23 percent say they won't get behind the wheel, says the survey of teens in the 30 states that have lowered the legal levels for blood alcohol.
"We found that these laws were effective in reducing both of these key outcomes," says co-author Alexander Wagenaar, a professor of epidemiology at the University of Minnesota's School of Public Health in Minneapolis. "We looked at states before and after they implemented these laws and controlled for broader trends and practices among teen-agers. These estimates are attributable to the effects of these new policies."
Laws to lower blood alcohol limits to 0.01 blood alcohol levels for teen-agers and those under 21 was first initiated in 1984, Wagenaar says. A 150-pound teen-ager who drinks one 12-ounce beer in 30 minutes would be at that level. "The whole wave of changing these laws started in 1984, and by the time we got to the 1990s, all 50 states had passed blood-alcohol limits for teen-age drivers. These laws were designed basically to prevent teen-agers from drinking any alcohol."
Wagenaar used data from the University of Michigan's Monitoring the Future Project, a survey of more than 5,000 high school seniors in 30 states between 1984 and 1998. Wagenaar asked the seniors how many times they had driven after drinking alcohol in the past two weeks, as well as after having five drinks in a row. He also asked the high school seniors if there was a passenger in the car when they were drinking and driving.
In 1999, 22 percent of 16- to 20-year-old drivers killed after crashes had blood alcohol concentrations of 0.10 percent or more, the Insurance Institute for Highway Safety reports. A 150-pound man drinking five, 12-ounce beers in one hour would be at that limit. Teen-age drivers with blood alcohol concentrations in the 0.05 to 0.10 percent range are far more likely than sober teen-age drivers to be killed in single-vehicle crashes -- a rate 18 times more likely for males and 54 times more likely for females.
Even though the results of the survey are self-reported, they are accurate, Wagenaar says. "We did this same survey every year, and while there's always an overall underestimate of drinking in these surveys, the amount of that undercount is consistent. So we know from that that this data is an accurate representation of what's going on."
The findings appear in the May issue of the American Journal of Public Health.
The message here is that these blood alcohol content laws work, Wagenaar concludes. "We saw the same kind of implications in previous changes, like changing the drinking age to 21. That was clearly effective in reducing car crash rates, violence and other problems among teen-agers."
Mothers Against Drunk Driving (MADD) agrees.
"These zero tolerance laws are laws that complement minimum-age drinking laws," says Wendy Hamilton, a mother of three college-age children and the volunteer national vice president of field issues for MADD in Charlotte Hall, Md. "They put more teeth into minimum-age driving laws and strengthen them, and obviously what's happening is kids are listening."
There's still lots more work to do, Hamilton says. "People have to realize that alcohol is the No. 1 killer of our youth. Alcohol kills 6½ times more kids than all other illicit drugs combined."
"We are still seeing too many kids getting killed, too many kids climbing into the front seat of cars with friends who have been drinking," Hamilton continues. "We've got to get at attitudes; we've got to get at preventing; and we've got to get kids to think before they get in a car or pick up that bottle."
What To Do
For more information on teen-age drinking and driving see the Insurance Institute for Highway Safety or Students Against Driving Drunk. If you'd like to check your own drinking habits and blood alcohol levels, here's a calculator to help you.
Or read these other HealthScout stories on teen drinking.
