Wednesday, 14. September 2011
The Intoxilyzer 5000 breathalyzer machine doesn’t just catch drunk drivers. There are many factors other than alcohol that can influence a breathalyzer test result. As a result, many American drivers are at risk of getting a DWI, even if they haven’t been drinking.
How Does the Breathalyzer Work?
It is crucial to understand that the breathalyzer does not measure the alcohol content of blood. Only a blood test can measure blood content.
The breathalyzer actually measures electrical current. When a person has been drinking, this electrical current is produced when an ethanol (ethyl alcohol) is oxidized to acetic acid (vinegar) at the test site. The current is processed by the machine and then converted into an approximation of blood alcohol content.
Minnesota police use the Intoxilyzer 5000, an infrared radiation breath test machine. When a person breathes into the chamber, the device sends out an infrared beam of light through the breath sample. The machine then measures the wavelength of the beam of light. Chemicals oxidizing from the alcohol group absorb more light and will send a higher reading back to the machine.
The Breathalyzer and Diabetes
Acetone is a chemical compound naturally produced in the human body. It is also oxidized in the same way the body processes ethanol. The average person does not produce high enough levels of acetone to create a measurable reaction. However…
People with diabetes may have acetone levels hundreds or thousands of times higher than the average person. The infrared beam cannot distinguish between ethanol and acetone, so a person with diabetes could very easily get a false-positive breathalyzer test.
The Breathalyzer and the Low-Carb Diet
Diabetics aren’t the only people with high levels of acetone in their body. A ketogenic diet is a high-fat, high-protein, low-carb diet. The diet which burns the pounds rapidly also spikes acetone levels in the body. This can, and has, led to false-positive breathalyzer tests.
The Breathalyzer and Asthma Inhalers
Researchers have found that inhalers taken for asthma can produce high, inaccurate breathalyzer readings—even those inhalers without ethanol. In Spain, a research study on an infrared spectrometer (like the Intoxilyzer) produced startling results:
All of the test subjects had baseline results of zero. After a puff on the inhaler, every one of the participants had breathalyzer readings above the legal limit.
The Breathalyzer and Your Lungs
The infrared spectrometry breath test requires that a person breathe for 4-5 seconds, and that the volume of their breathe must be at least 1.5 liters. Studies have shown that people with smaller lung capacity can obtain highly inaccurate BAC levels or may be unable to register a reading at all and may be seen as refusing to test. Conditions that lead to smaller lung capacity include:
- Any other congenital lung disease
The Breathalyzer, Fumes, and E85
In a study of fumes on the Intoxilyzer 5000, researchers sprayed paint in a room for 20 minutes while a subject wore a protective mask. The subject, a professional painter, was then given a breath alcohol test. Although a blood test showed no alcohol, the breathalyzer reading was 0.075—barely under the legal limit.
This study could also prove problematic for the growing number of drivers using E85 to fuel their vehicles. The ethanol-based fuel produces ethanol emissions which, if inhaled, could alter BAC results.
The Breathalyzer and Acid Reflux
People suffering from gastroesophageal reflux disease (GERD) have an increased risk of getting a false-positive result above the legal limit on a breath-alcohol test. Even if only a very small amount of alcohol is consumed, many GERD patients have tested above the legal limit of 0.08, placing them in danger of a DWI conviction.
Because of all the above factors it is essential that you contact a DWI defense lawyer if you are ever arrested for drunk driving.
Clean Air Trust
University of Washington
St. Louis College of Pharmacy
Bmj.com (British Medical Journal)
International Journal of Obesity