How Smoking Can Affect Your Breathalyzer Test Results

Categories: Criminal Defense

A field officer asking a driver to complete a field sobriety test.

Note: This article has been refreshed and revised as of February 28, 2024, to ensure the information remains current and accurate.

If you have ever experienced the misfortune of being stopped by law enforcement for DUI, you are aware of how it can upend your life. Even first time DUI’s can result in up to a year of probation and suspension of driving privileges, as well as having other collateral repercussions in your life. 

As you likely know, if you are pulled over by the police and suspected of driving under the influence (DUI) or driving while Abilities Impaired (DWAI), the officer may ask that you take what is known as a breathalyzer test. These tests have been used for years with some general accuracy, and are often used as the basis for prosecuting DUI’s in court. But are these tests always accurate; if not, when are they inaccurate? In this article, we will examine some things that may cause a false positive or at least increase the chances that the test will show a higher alcohol level than it should. Surprisingly, smoking is one of those things that may cause an inaccurate reading. Let’s explore a little further, including what can throw off a breathalyzer and what besides alcohol can set off a breathalyzer.

Does smoking affect breathalyzer tests? If you find yourself in a situation involving a breathalyzer test or facing DUI charges, don’t navigate it alone. Seek professional legal advice. Contact us today for a confidential consultation with experienced attorneys who can guide you through the process and explore your defense options.

History of the Breathalyzer and How It Works

Believe it or not, the breathalyzer in one form or another has been around since 1938. It all started way back in 1874 when physician, Francis Edmund Anstie, observed that breath actually excreted alcohol and that we could measure this excretion. However, it wasn’t until 1938 that Professor R. N. Harger introduced the Drunkometer. From there, the breathalyzer evolved into such products as the Intoximeter by Professor Glen Forester and the Alcometer by Professor Leon Greenberg, both introduced in 1941. It wasn’t until 1954 that Professor Robert F. Borkenstein introduced the Breathalyzer, which became the common name for breath alcohol measuring devices from that point on.

The most common breathalyzer used by modern law enforcement in the field is the electrochemical fuel cell breathalyzer. This device measures the chemical reaction that takes place because of the oxidation of alcohol/ethanol into acetaldehyde. This reaction produces an electrical current that triggers the indicator lights on the device.

Does Smoking Affect Breathalyzer Test

Scientific research has proven that smokers have a higher level of acetaldehyde in their lungs. Even if the smoker is completely sober, the acetaldehyde in a smoker’s lungs will show up on a breathalyzer test as if they were drinking. Now, if the smoker has had a drink or two, then the indicator on the breathalyzer will be higher than if that person was a non-smoker. This is because the device cannot distinguish between the acetaldehyde created by the oxidation of alcohol and the acetaldehyde that was already in the smoker’s lungs.

Surprisingly, smoking has the effect of slowing down the absorption rate of alcohol into the bloodstream. This fact leads to an ironic result: Even though the breathalyzer shows a higher concentration of alcohol than is present in the smoker’s bloodstream, that person is absorbing the alcohol more slowly and is likely to be less impaired than a non-smoker. In other words, if you are a smoker, you are likely to be less impaired than a breathalyzer says you are. 

In Colorado, marijuana use is legal for those over 21 years of age. So you may be wondering if marijuana smoke can produce the same effect on breathalyzer results by showing a higher reading than should be registering. The answer is, “Yes.” Marijuana smoke does produce increased levels of acetaldehyde and therefore may alter breathalyzer test results.

What Besides Alcohol Can Set Off a Breathalyzer: Other Factors That May Affect Test Accuracy

In addition to cigarette or marijuana smoke, there are a surprising number of things that may also be what can throw off a breathalyzer. 

Contamination of the Mouth – Things like mints, lozenges, lip balm, dental adhesive, smokeless menthol tobacco, asthma inhalers, and even dental work could give a positive reading, even when you haven’t been drinking.

Operator Error – An example of an operator error would be if the officer does not follow the operator’s manual or doesn’t follow the 20-minute rule before administering the breathalyzer test.

Outside Power Sources – Believe it or not, if the police room where the breathalyzer is being administered does not have a dedicated and grounded power circuit for the breathalyzer device, then microwaves, coffee pots, toaster ovens, and even cameras may affect the result of the test.

Physical Condition – Several physical conditions may cause an inaccurate readout from the breathalyzer as well. These include:

  • Dieting – if on a high protein regimen or fasting
  • Gastric Reflux
  • Hyperventilation before a test
  • Vomiting before a test
  • Diabetes
  • Prescription drugs
  • Liver disease and renal dysfunction
  • Body temperature

You may be surprised to learn that just a one-degree increase in your body temperature will result in a .03% increase in your blood alcohol concentration or BAC.

You Need an Experienced Defense Attorney by Your Side If You Are Arrested for DUI

If you or a loved one has been arrested for DUI in Colorado, you must speak with a lawyer at Mark S. Rubinstein, P.C., as soon as possible. We have an experienced defense legal practitioner, and we know the common errors that are made in administering breathalyzer tests as well as the myriad of other things that can create inaccurate results. These inaccurate results, if not properly defended against, can cause you to be unfairly penalized by our judicial system. Do not let this happen to you. Allow us to put our years of experience and our in-depth knowledge of defenses against DUI convictions to work for you.

A DUI on your record can negatively impact your life for years to come. It can not only affect your ability to drive, but it can even impact your ability to get that job you have been working towards for years.  Do not allow your DUI to have any worse impact on your life than necessary. Contact us today for a free consultation by calling our office or filling out our online contact form. We are here for you!

Mark Rubinstein

Attorney Mark S. Rubinstein has been practicing law for more than 30 years, including 25 years in Colorado. He founded Mark S. Rubinstein, P.C., in Carbondale after working for law firms in Denver and earlier in his career in San Diego. He focuses his practice in the areas of criminal defense and personal injury representation, and he is well known throughout western Colorado as an effective and unwavering advocate for his clients.