When you hear someone mention the phrase “drunk driving,” images of a person standing on the side of one of Media’s roads blowing into a hand-held breath testing device likely enter your mind. Indeed, the breath test has essentially become the de facto perception of a DUI charge.
This actually prompts many of those that come to see us here at The Law Offices of Joseph Lesniak, LLC to question why would law enforcement officials measure one’s breath to determine the alcohol content of their blood (you may share the same question). Comprehending the answer requires that you understand the pathway alcohol travels from you consuming it to subsequently breathing it out.
Ethanol escaping your body when you breathe
According to the Alcohol Pharmacology Education Partnership, the type of alcohol used in beverages is ethanol. When you consume ethanol, it breaks down into its component molecules, which (due to it being a water-soluble compound) can then pass through the organs of your digestive tract through a process known as passive diffusion. From there, it enters into your bloodstream and is then transported throughout your body via the veins. Eventually, that ethanol ends up in your lungs, where some of it vaporizes upon coming into contact with oxygen. That gaseous alcohol then leaves your body when you breathe.
Pointing out deficiencies with breath testing
The aforementioned process continues as the ethanol works its way out of your system through metabolism. The rate of vaporized alcohol must remain in equilibrium with the concentration still in your blood. The fact that concentration lowers with each breathe may highlight some of the shortfalls of breath testing (as your BAC is technically lowering with each breath, which makes getting an accurate measurement akin to hitting a moving target).
You can find more information about challenging DUI charges throughout our site.