IOWA CITY, Iowa—
— Timothy Brown has put hundreds of drunken drivers behind
the wheel.
In the research center where he works, the drivers ingest
vodka or 151-proof alcohol and get behind the wheel of a Chevrolet Malibu
mounted in a metal pod about the size of a two-car garage. Then they take a
spin in what's considered the world's most sophisticated driving simulator,
while Brown and his colleagues gather data.
Brown is using that data to better understand the difference
in driving abilities of someone who is sober, someone who has had a few drinks
and someone who has had a few more drinks. That work has been made especially
timely by a controversial National Transportation Safety Board recommendation
to lower the legal limit of intoxication to a blood alcohol content of 0.05
from 0.08.
Brown, senior research associate at the $100 million
National Advanced Driving Simulator in Iowa, is looking to isolate the precise
differences in driving performance with no alcohol in the blood and at a level
of 0.05. His work is expected to shed light on the national debate.
"My heart doesn't tell me anything," Brown said
when asked for his best guess on whether 0.05 was serious impairment. He
acknowledges that diminished performance happens at 0.05 but would not
elaborate "because I'm a researcher and the data drives me."
Over Labor Day weekend, one of the busiest holiday driving
weekends when an estimated 30 million drivers will take to the roads,
authorities will be on the lookout for those who attempt the potentially
dangerous mix of drinking and driving. But what constitutes dangerous driving
is once again up for debate.
Calling impaired driving "a national epidemic,"
NTSB Chairwoman Deborah Hersman made the 0.05 recommendation in May. It was one
of several proposals that include high-visibility DUI enforcement, expanded use
of alcohol-sensing technology and ignition interlock devices, and more DUI
treatment courts.
Research suggests that lowering the legal limit of
intoxication to 0.05 could save 500 to 1,000 lives a year.
But many safe-driving advocates are conspicuously silent on
the issue of whether 0.05 is high enough impairment to merit criminal charges.
Mothers Against Drunk Driving is standing down, as is Illinois Secretary of
State Jesse White. The venerable Insurance Institute for Highway Safety, which
notes that it never takes formal positions on policy, said police will have
trouble enforcing 0.05.
At the core of concerns about 0.05 is the tricky issue of
when alcohol impairment becomes criminally negligent. How does slight alcohol
impairment differ from impairment caused by drowsiness, cellphone use,
medication, aging or other conditions? Is it reckless to get behind the wheel
after two glasses of wine at a dinner party? A large beer at a Blackhawks game?
A couple of cocktails at a reception?
Research on the topic is voluminous — and resembles a
weaving car.
The National Sleep Foundation states that drowsiness is very
similar to alcohol impairment and "can impair driving performance as much
or more so than alcohol," according to a report on the topic. Being sleepy
can slow reaction times, limit vision and create lapses in judgment and delays
in processing information, the foundation states.
"In other words," the foundation reports,
"driving sleepy is like driving drunk."
A 2003 study by University of Utah showed that motorists who
talk on cellphones — hands-free or not — are as impaired as drivers at a 0.08
BAC. Study participants drove slower and hit the brakes and accelerated later
than those driving undistracted. Drunken drivers drove slower than cellphone
users and undistracted drivers but more aggressively. They also followed more
closely and hit their brakes more erratically, the research showed.
As to whether such a thing as responsible drinking and
driving exists, some research shows that lane deviations and attention lapses
occur at a BAC as low as 0.001. MADD and the National Institute on Alcohol
Abuse and Alcoholism recommend no one drive after drinking.
But the American Beverage Institute, which represents restaurant
and bar owners, calls the 0.05 recommendation an effort to "criminalize
perfectly responsible behavior," saying that less than 1 percent of
traffic fatalities in the U.S. are caused by drivers with a BAC from 0.05 to
0.08. The organization points to National Highway Traffic Safety Administration
data showing that 70 percent of drunken driving deaths involve a driver with a
BAC of 0.15 or higher.
In making its recommendation in May, the NTSB noted that
more than 100 countries, including many in Europe, have set 0.05 as the legal
limit of intoxication and experienced significant drops in traffic fatalities
after doing so. Drunken driving accounts for nearly 10,000 traffic fatalities a
year in the U.S.
"The research clearly shows that drivers with a BAC
above 0.05 are impaired and at a significantly greater risk of being involved
in a crash where someone is killed or injured," the NTSB's Hersman said in
recommending the lower level.
Sarah Longwell, managing director of the American Beverage
Institute, contends the NTSB research lacks context. The significantly greater
risk that the NTSB points out is no different than the risk that accompanies
listening to a loud car radio or having a passenger talking to the driver, she
said.
Emphasizing other countries that set their legal definition
of intoxication at 0.05 is "an apples to oranges comparison" to the
U.S., Longwell said. Many of those countries have "vastly different"
driving, mass transit and drinking cultures, she said. In addition, the
countries imposed "other draconian measures," including random breath
testing, that contributed to the decline in traffic fatalities and would be
unacceptable in the U.S., Longwell added.
"We're going to stand by 0.08 as the law," she
said.
'Pretty harsh'
Clarifying alcohol's effect on the body can be tricky.
Generally speaking, the liver, brain, pancreas and stomach
break down and eliminate alcohol through enzymes that convert the substance
into water and carbon dioxide, the U.S. Department of Health and Human Services
reports.
During that conversion, one of the enzymes metabolizes into
"a highly toxic substance and known carcinogen," acetaldehyde. That
substance and an alcohol-metabolizing enzyme known as cytochrome contribute to
the development of cancers in the respiratory tract, liver, colon or rectum and
breast, Health and Human Services research shows.
Alcohol's effect on the brain is considered harmful but
somewhat uncertain. In its 24-page "Beyond Hangovers: Understanding
alcohol's impact on your health," even the National Institute on Alcohol
Abuse and Alcoholism states, "There still is much we do not understand
about how the brain works and how alcohol affects it."
What research does show is that alcohol can slow
communication between chemical neurotransmitters that carry messages between
the brain's estimated 100 billion neurons. Some research indicates that
acetaldehyde may contribute to that impairment. Lab animals that received
acetaldehyde exhibited impaired coordination and memory and sleepiness,
according to research published in 2006 in the journal Alcohol Research &
Health.
Brain regions most vulnerable to alcohol include the
cerebellum, which controls motor skills; the limbic system, where memory and
emotion are centered; and the cerebral cortex, which connects to the nervous
system and deals with the ability to think, plan, remember, solve problems and
interact socially.
The metabolism of alcohol varies based on genetics,
including variations in those enzymes, and environmental factors such as the
amount a person drinks and his or her diet, the Department of Health and Human
Services states.
"Regardless of how much a person consumes," a
department report notes, "the body can only metabolize a certain amount of
alcohol every hour," an amount "that varies widely among individuals
and depends on a range of factors, including liver size and body mass."
That wide variance may contribute to lawmakers' reluctance
to embrace 0.05 as the new drunk.
No Illinois legislators are pitching bills to lower the
legal level of intoxication, said state Rep. John D'Amico, D-Chicago, chairman
of the Vehicles and Safety Committee.
"You don't want anybody driving drunk, obviously,"
D'Amico said. "But this would be limiting everybody to one beer. That'd be
pretty harsh."
He also said the lower level "would have a domino
effect." Restaurants, bars and sports stadiums would suffer.
Call for ignition interlocks
Illinois Secretary of State White, considered a leader in
fighting drunken driving, is taking a pass on tinkering with the 0.08 level
(adopted in 1997), a spokesman said. White is planning instead to push for
legislation that would expand for repeat offenders the use of ignition
interlocks — in-car breath testers that prevent the engine from running if
alcohol is detected on the driver's breath, the spokesman said.
Wider use of ignition interlocks is central to MADD's
efforts, too. J.T. Griffin, the organization's senior vice president of public
policy, said MADD supports 0.08 as the limit of legal intoxication in large
part because research over 50 years shows definitively that everyone is
seriously impaired at that level. Impairment below 0.08 becomes a little more
uncertain.
Griffin said pushing to make 0.08 the law "was such a
tough battle to fight. We sort of established it as the across-the-board
level."
MADD is taking a more practical approach — including
recommending that ignition interlocks be mandatory for all DUI offenders — in
continuing its fight against drunken driving. Twenty-one states and four
counties in California require interlocks for all drunken driving offenders. In
Illinois, first-time DUI offenders must obtain one if they want to drive.
"We're doing a lot of really positive things,"
Griffin said, "and we feel like we've got a lot of momentum. To shift to
0.05 really goes against what we're doing."
Like many, Griffin said impairment happens below 0.08, but
"what that level is, I don't really know."
Which is why Brown's work at the simulator may be
illuminating. He said he's downloaded the data file from a key 2008 project
that focused on blood alcohol levels and impaired driving and will begin
re-crunching the analysis in a couple of weeks. He may have preliminary results
in October, he said.
But getting there won't be as exciting as watching the pod
slide, tilt and spin in the research center.
"This," Brown said, "mainly involves sitting
in front of a computer screen."
tgregory@tribune.com
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