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Pro golfer Rachel Connor is facing DUI charges after being arrested in Sarasota, Florida.
According to TMZ, she was driving with NFL star Eddie George when she got pulled over. Cops said they noticed her speeding and weaving in her lane.
Conner, had trouble walking straight. She was given a breathalyzer test and blew a .133.
Eddie George was not arrested but took a cab home after the incident.
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As a DUI specialist Orange County, I get asked a lot whether or not it’s better to take a breath test, or a blood test, and I usually give the advice to choose breath. (Although there is a split of opinion on that, and some attorneys recommend blood). The presence of mouth alcohol, temperature, partition ratios, and the math effort used to convert breath to a blood alcohol level gives some room for argument.
One of the best ways to lower a breath test, however, is to hyperventilate, which cools the airways and, as breathalyzers are temperature dependent, makes for a lower test. The academic studies seem to bear this out:
“…a group of men drank moderate doses of alcohol and their blood-alcohol levels were then measured by gas chromatographic analysis of their breath. The breathing techniques were then varied.The results indicated that holding your breath for 30 seconds before exhaling increased the blood-alcohol concentration (BAC) by 15.7%. Hyperventilating for 20 seconds immediately before the analyses of breath, on the other hand, decreased the blood-alcohol level by 10.6%. Keeping the mouth closed for five minutes and using shallow nasal breathing resulted in increasing the BAC by 7.3%, and testing after a slow, 20-second exhalation increased levels by 2%. “How Breathing Techniques Can Influence the Results of Breath-Alcohol Analyses”, 22(4) Medical Science and the Law275.For another study with similar findings, see “Accurate Measurement of Blood Alcohol Concentration with Isothermal Breathing”, 51(1) Journal of Studies on Alcohol 6.
Dr. Michael Hlastala, Professor of Physiology, Biophysics and Medicine at the University of Washington has gone farther and concluded:
“By far, the most overlooked error in breath testing for alcohol is the pattern of breathing….The concentration of alcohol changes considerably during the breath…The first part of the breath, after discarding the dead space, has an alcohol concentration much lower than the equivalent BAC. Whereas, the last part of the breath has an alcohol concentration that is much higher than the equivalent BAC. The last part of the breath can be over 50% above the alcohol level….Thus, a breath tester reading of 0.14% taken from the last part of the breath may indicate that the blood level is only 0.09%.” 9(6) The Champion 16 (1985).
The one thing that seems pretty clear is that holding your breath (which police sometimes ask you to do) results in a much higher test. That can make the difference between being over the limit and under the limit. Be careful out there, and if you need an attorney, my number is (877) 568-2977.
Lawrence Taylor, in his excellent duiblog (duiblog.com), points out that “breathalyzers” do not measure alcohol: they actually measure the presence of a molecular group in chemical compounds. Ethyl alcohol (aka ethanol) contains the group, and so when the machine detects its presence (or, more accurately, infrared energy is absorbed by it), it simply assumes that the detected compound must be ethyl alcohol.
Problem: there are thousands of compounds containing the molecular group  of which well over one hundred have been found on the human breath.
Breathing gasoline or paint fumes, for example, or merely absorbing the fumes through the skin, can create false breath test results for days afterwards. And as Dean taylor has posted in the past, the problem is particularly acute when the suspect happens to be a diabetic, as diabetics often have high levels of acetone in their breath  a compound which contains the group in its molecular structure.
However, you do not need to be a diabetic to have high levels of acetone. Scientific research has established that acetone can exist in perfectly normal individuals at levels sufficient to cause false high breath-alcohol test readings.  See “Excretion of Low-Molecular Weight Volatile Substances in Human Breath: Focus on Endogenous Ethanol”, 9 Journal of Analytical Toxicology 246 (1985).
Fasting or radical dieting, such as with the Atkins diet, can also cause significantly elevated acetone. Studies have concluded that fasting, for example, can increase acetone in the body sufficient to obtain breathalyzer readings of .06%.  This is cumulative  that is, the .06% will be added by the machine to any levels actually caused by alcohol or other compounds.  Thus, a true breath alcohol of .03%, for example, would be reported by the machine as .09%. “The Likelihood of Acetone Interference in Breath Alcohol Measurement”, 3 Alcohol, Drugs and Driving 1 (1987).  And low-carbohydrate diets have long been associated with high levels of acetone production.
Of course, for many years law enforcement denied that any such problem existed.
How reliable are breathalyzers? Not very.
From the popular website Cracked.com:
“Blood alcohol content, or BAC, is a measurement by volume of alcohol in your body. It can be taken with a blood test or with a breathalyzer. Here is a helpful chart for understanding what the numbers mean:…”
http://www.cracked.com/funny-1095-blood-alcohol-content/
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