Although breath testing is widely used to measure blood alcohol content (BAC), it is not appropriate for all people. Breath testing measures the amount of alcohol that is evaporated from the alveolar tissue in the lungs. Breath is expelled from the deepest portion of the lungs, passes through the throat, and then exits from the mouth. However, where residual alcohol is retained in the mouth, the resulting BAC reading will reflect mouth alcohol and not deep lung air.

Scientifically, it has been shown that mouth alcohol dissipates in 15 minutes. For this reason, police officers are mandated to “continuously" observe the test subject for 15 minutes prior to initiating a breath test. This 15-minute observation period is necessary in order to discount contaminants from skewing the result. Contaminants include: additional alcohol, food, gum, breath strips, asthma inhalers, tobacco, and other substances which may affect alcohol readings. However, even when a person does not ingest anything 15 minutes before a test, there are other problems which affect mouth alcohol, namely the subject having dental work or suffering from acid reflux, also known as GERD.

GERD

Gastroesophageal Reflux Disease, also known as GERD, is the term used to describe a backflow of acid from the stomach into the swallowing tube or esophagus. Almost everyone experiences gastroesophageal reflux at some time. The usual symptom is heartburn, an uncomfortable burning sensation behind the breastbone, most commonly occurring after a meal. In some individuals reflux is frequent or severe enough to cause more significant problems and to be considered a disease.

GERD occurs when the pyloric valve, which separates the stomach from the esophagus, does not close completely, thus causing liquids and gasses from the stomach to rise into the throat and oral cavity.

People who have GERD will show disproportionately high readings on breath machines because of the resulting mouth alcohol. This is because the alcohol from the stomach rises into and permeates the mouth and throat, mixing with the breath passing from the lungs, through the throat and mouth, and into the machine. Any BAC result is going to reflect absorbed alcohol from the stomach, and not the distributed and eliminated alcohol that should be reflected in breath tests.

GERD occurs beyond the control of the person, who cannot stop it in order to take a breath test. Even if the police officer continuously observes the person for 15 minutes, the officer can’t observe GERD.

Dental Work

Anyone who has had dental work, such as dentures, bridges, or braces on the teeth may retain mouth alcohol. Alcohol becomes trapped with food particles and gets retained in the crevices of dental work. Other contaminants get trapped as well, like mouthwash, cough drops/syrup, and breath strips. Denture wearers are at risk because of the risk of food and alcohol getting trapped in the space between the dentures and the gums. Even where dental adhesives are applied, contaminants get trapped. Bridge wearers are also at risk for this same reason. People who have braces in their teeth are very aware that food particles become trapped in the metal. Additionally, people who have had teeth removed or where wisdom teeth have grown in may have “pockets" where food gets trapped. Where the alcohol is trapped along with food, it does not dissipate in the 15 minutes that the police officer waits before initiating a breath test. Thus, mouth alcohol remains in the mouth. The resulting BAC levels will reflect a disproportionately high alcohol reading.

Some types of food create alcohol readings as well. Bread products that contain yeast, such as white bread, sourdough bread, pretzels, pastries, doughnuts, etc., may get lodged in the teeth, dentures, or dental work. Alcohol is produced by the fermentation process in yeasts. Even when baked, the dough may retain some alcohol, although not enough to make a person feel intoxicated. However, the readings may be reflected on the breath test. Even a small amount of alcohol in the mouth will have a huge difference in BAC readings on the breath machines.

Although breath testing is a widely used and popular method of determining blood alcohol levels, it is not conclusive and is not always accurate. There are many factors that can skew a breath result, where a test will show high levels of alcohol present, even where it is not so. Breath tests are designed to measure deep lung air, but if mouth alcohol is present, the tests don’t show deep lung air. Instead, they reflect mouth alcohol. It does not take much mouth alcohol to skew the results, resulting in arrest and conviction for DUI. Many studies have proven that mouth alcohol reflects BAC. Police agencies have tried to keep up with science, in installing “slope detectors" to detect mouth alcohol. But, where food and alcohol get lodged in the teeth, under dentures, or in pockets of the gums, or where a person suffers from GERD, a slope detector does not help and in fact offers a false sense of security in the BAC readings.

To lay a good defense, science and the law must come together in order to prove that the breath tests were inaccurate. Any conviction for a DUI is treated like a brand of shame, which is even more horrible when it is based on false tests. An experienced DUI attorney is necessary to fight the case with all the weapons necessary. DUI cases are specialized because of the science behind the testing procedures, which are used to convict for DUI. An experienced DUI defense attorney will have the knowledge and the experts to prove your case, and prove your innocence. No one should be convicted because of bad science. A knowledgeable and skillful attorney will know the best defenses and fight for your rights.