Pubdate: Thu, 06 Sep 2012
Source: Gazette, The  (Cedar Rapids, IA)
Copyright: 2012 Gazette Communications
Contact: http://thegazette.com/guidelines/#gform_fields_26
Website: http://thegazette.com/
Details: http://www.mapinc.org/media/3847
Author: Vanessa Miller

UNIVERSITY OF IOWA TESTING EFFECTS OF POT ON DRIVERS

Study Will Be First of Its Kind

Marijuana use, despite the legal implications, has been common in 
America for generations, and it's becoming even more widespread as 
some communities legalize it for medical purposes.

But it wasn't until five years ago that the National Highway Traffic 
Safety Administration looked into its prevalence behind the wheel and 
found that 16.3 percent of the weekend nighttime drivers surveyed at 
300 locations across the United States were drug positive.

Cannabis stood out as the most commonly detected drug, according to 
the survey. But what the survey didn't show - and what authorities 
don't know - is how often drivers are impaired by the drugs, 
specifically marijuana.

Some states prohibit drugged driving all together while others 
require proof of impairment, but few studies have actually analyzed 
the effects of cannabis behind the wheel - until now.

The National Highway Traffic Safety Administration is teaming up with 
the National Institute on Drug Abuse to conduct the first study to 
analyze the effects of inhaled cannabis on driving performance. The 
study is taking place at the University of Iowa's National Advanced 
Driving Simulator, praised as being the most advanced simulator in 
the world, and pilot work is scheduled to begin later this month.

Marilyn Huestis, chief of chemistry and drug metabolism at the 
intramural research program for the National Institute on Drug Abuse, 
has been trying to get the UI simulator involved in drugged driving 
studies for years. New, top-quality research could help shape future 
legislation in the United States, which Huestis said is behind in its 
policies on drugged driving.

"It's so important for it to be done there," she said. "But it's 
taken a lot to get the United States to recognize the problem."

'Very legal'

The study will use about 20 volunteers, ages 21 to 55, who live 
within 40 miles of the UI and are able to make eight study visits - 
six of which will involve overnight stays at the University of Iowa 
Hospitals and Clinics. Participants must be in good health, have good 
sleep habits and be alcohol and marijuana consumers.

They must be willing to go through drug and pregnancy screenings, 
including blood draws.

Huestis said the study had to be approved by boards associated with 
the UI, the Federal Drug Administration and other local and national 
drug enforcement agencies.

"The regulatory reviews are extensive and meant to develop a study 
with high merit," she said.

Cannabis used in the study will come from a federally funded 
laboratory at the University of Mississippi, the nation's only 
facility allowed to grow marijuana for medical and research purposes. 
It involves a "tightly controlled process" involving the FDA and the 
U.S. Drug Enforcement Administration, according to Huestis.

"It is all very legal," she said. "We have all the approvals in 
place, and we are starting the pilot data - but it's very costly and 
difficult to perform."

Volunteers for the UI study will be transported to and from the study 
- - they will not be allowed to drive while participating - and they 
will be "dosed" under the supervision of medical professionals, 
driving simulator officials said.

Volunteers will get paid to participate in the study, although 
compensation amounts are kept private.

And, even though participants will be asked to disclose details of 
their marijuana use, the UI uses a "certificate of confidentiality" 
from the U.S. Department of Health and Human Services that protects 
information about participants. The certificate, according to UI 
officials, verifies that no information about participants will be 
disclosed to anyone, including law enforcement.

Known effects

Although few studies have been done on how marijuana affects a 
person's ability to drive, decades of research has shown its effects 
on the brain.

"It is very much involved in movement and control," Huestis said, "in 
memory and decision making."

Driving requires a lot of divided attention, with the need to stay in 
a lane, track turns in the road, monitor other drivers and handle 
unexpected events that might require a person to slam on the breaks 
or swerve, according to Huestis. Cannabis affects a person's ability 
to divide his or her attention, which is why, in crafting the drive 
for the study, Huestis included a number of unexpected occurrences. 
She also crafted a portion of the trip at the other extreme.

"There are long periods of monotonous driving, because it turns out a 
person's ability for sustained attention also is dramatically 
affected by cannabis," she said.

Tim Brown, associate research scientist with the UI's advanced 
driving simulator, said plenty of research has been done on the 
effects of drinking alcohol and driving, and with the prevalence of 
marijuana use today - especially considering the 2007 roadside survey 
findings - similar impairment data is needed for the drug.

"We don't know what the impacts are," he said. "And that creates 
challenges when someone has a medical marijuana card." Buy this photo

National Advance Driving Simulator operator Jeff Gordon of Cedar 
Rapids monitors the NADS-1 from the control room at the facility in 
the University of Iowa Oakdale Research Park in Coralville. (Brian 
Ray/The Gazette)

Medical marijuana is legal now in 17 states and Washington D.C., 
although it is illegal in all states to drive under the influence of 
any drug, regardless of whether it was prescribed by a physician, if 
the drug is causing impairment.

Impairment can be difficult to prove, but 17 states - including Iowa 
- - have passed "drug per se" laws that simply make it illegal to 
operate a vehicle with certain drugs in one's system. Most of those 
states, like Iowa, do not tolerate any amount of the prohibited drugs 
in a driver's system.

Huestis said the list of states with drug per se laws is growing, and 
there is a push for a federal pro se law that would create a blanket 
prohibition against driving with one of the prohibited drugs on board.

Education, through studies like the one about to take place at Iowa, 
is expected to further the discussion about legislation and enable 
more-informed enforcement, Huestis said. It could even aid in the 
creation of an equivalent to the 0.08 blood alcohol content level set 
for driving.

"From an education and prevention point of view, this is very 
important," she said.
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MAP posted-by: Jay Bergstrom