Sober N Clean

Experts doubt the effectiveness of consumer-grade breathalyzers

Holiday partygoers who plan to drink should beware: A public safety campaign will mobilize extra law enforcement from now until Jan. 2. That means some partiers will get designated drivers, while others will look for alternate transportation. And for those who plan to drive: Some marketers are touting personal breathalyzers that say they help drivers test their limits before they get behind the wheel.

Breathalyzers have been used by law enforcement agencies for years to test blood-alcohol levels, which can be detected by measuring the amount of alcohol in a person's breath. Similarly, some consumer breathalyzers, which can cost from $16 to $1,000 and range from small key chain gauges to handheld detectors, claim to provide an accurate digital blood-alcohol-content reading, or BAC, in seconds.

Massachusetts State Police captain Daniel Wicks says that if these devices work, "they might be a good aid in educating and informing the driver."

Others caution drivers against using them. "These consumer breathalyzers are interesting and may make you more aware of your BAC, but there's no evidence to show that it's an effective way of keeping people from driving while impaired," says Linda Degutis, an associate professor at Yale University who studies alcohol interventions and policies. "In fact, they may give people a false sense of security."

To be sure, consumer breathalyzers, while compact and relatively easy to use, do not give legally admissible results. Expensive equipment that provides such results requires regular calibration and maintenance and must be operated by certified personnel. And even the validity of those tests is regularly challenged in court.

When in the market for a consumer breathalyzer, the more expensive models may be better. Mac Forrester, owner of Intoximeters Inc., a St. Louis maker of equipment for industrial applications such as workplace substance abuse testing, says that mass market alcohol screeners using semiconductor chips are not as stable as those that use infrared devices or fuel cell sensors. The inexpensive chips are prone to false positives, which even can be caused by the acetones in a marathon runner's breath, detected after burning fat during exercise.

"These consumer breathalyzers sell because of the price and ignorance of the purchasing population," Forrester says.

Conversely, he said more expensive models, which use more reliable technology such as infrared or fuel cell technology, yield more accurate results. These professional-level models, which range from $400 and up, can be purchased by the general public.

No matter which device you choose, Barbara Harrington, state executive director of Mothers Against Drunk Driving, says the organization does not recommend monitoring blood-alcohol content and then making a decision about whether to get behind the wheel. Instead, she says people should make a plan for sober driving before drinking begins.

"Some folks who drink are searching for that sweet spot between sobriety and being illegal at .08," says Harrington. "But it doesn't make sense that a person can manage drinking by testing themselves and making a judgment based on test results."

source: The Boston Globe
© Copyright 2007 Globe Newspaper Company.