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Effects of Mouth Alcohol on a Breath Instrument

by A. Khan (co-op student to S. Biss)

DUI Lawyer & Student Experiment

Purpose:

To study effects of mouth alcohol on a breath instrument.

 

Apparatus:

Intoxilyzer SD-5

 

Materials:

Disposable mouthpiece

Fresh Burst Listerine

 

Procedure:

  1. Alcohol-free subject blows into Intoxilyzer SD-5 to be certain that Blood Alcohol Concentration (BAC), Breath Alcohol Concentration (BRAC), Mouth Alcohol Concentration (MAC) and Stomach Alcohol Concentration (SAC) readings are all at zero.

  2. Take a sip of Listerine Mouthwash swish it around in mouth, gums and discharge of it after cleansing mouth. Record Time.

  3. Blow into Intoxlyzer SD-5 at 2 minutes subsequent to the taste of the mouthwash.

  4. Record result to the trial sheet.

  5. Repeat steps 2-4 at 5 minutes, 10 minutes.

 

Alcohol Free

Subject blows .000

Results of Blood Alcohol Concentration (BAC) ratings prior to use of mouthwash. Subject is alcohol free and has no Blood alcohol concentration, Breath alcohol concentration,   Mouth alcohol concentration, or Stomach alcohol concentration

DSC02394.jpg

Second Test

Subject blows .039

Results of BAC readings after the second test.   Subject blows 39 mg/100 mL which is half the legal limit in Canada. Test taken 5 minutes after Listerine swished in mouth. Subject has consumed no alcohol.. Intoxilyzer indicated 39 mg/100mL even though subject has no actual has Blood alcohol concentration or Stomach alcohol concentration

DSC02396.jpg

Mouth Alcohol Source

Apparatus

Listerine bottle used in Mouth Alcohol Experiment. Contains ethyl alcohol.

DSC02395.jpg

Third Test

Subject blows .000

Results of BAC readings after the third test.  Test taken 10 minutes after Listerine swished in mouth.

DSC02393.jpg

First Test

Subject blows .194

Results of BAC readings after the first test. Subject blows 194 mg/100 mL which is 2 1/2 times the legal limit in Canada. Test taken 2 minutes after Listerine swished in mouth. Subject has consumed no alcohol. Intoxilyzer indicated 194 mg/100mL even though subject has no actual has Blood alcohol concentration or Stomach alcohol concentration

Results for Alcohol Experimentation
Mouth Alcohol Results
moutha1.gif

Conclusions:

​

Through this experiment, it is evident that the effects of Mouth Alcohol do not affect the overall Blood Alcohol Concentration readings on an Intoxilyzer SD-5 unless the subject test is taken shortly after alcohol is placed in the mouth.  When undertaking any  breath instrument test, the operator should always make sure that the last drink was consumed and no new alcohol was introduced into the mouth 15-20 minutes prior to the test. 

​

It is also evident that recent mouth alcohol can have a profound impact on the readings of the Intoxilyzer SD-5.

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If you are a member of the public, please don't attempt to use what you see or read at this site in Court. It is not evidence. The author is not a scientist. The author has a great deal of experience in cross-examining scientists about these issues, but the author is not a scientist. Hire a criminal lawyer in private practice in Ontario. Your lawyer can retain an expert. The author is a retired lawyer, not a lawyer in private practice. Read the statement of the purpose of this web site below.

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WARNING: Please do not attempt to use any text, image, or video that you see on this site in Court. These comments, images, and videos are NOT EVIDENCE. The Courts will need to hear evidence from a properly qualified expert. The author is not a scientist. The author is not an expert. These pages exist to promote discussion among defence lawyers.

Intoxilyzer®  is a registered trademark of CMI, Inc. The Intoxilyzer® 5000C is an "approved instrument" in Canada.

Breathalyzer® is a registered trademark of Draeger Safety, Inc., Breathalyzer Division. The owner of the trademark is Robert F. Borkenstein and Draeger Safety, Inc. has leased the exclusive rights of use from him. The Breathalyzer® 900 and Breathalyzer® 900A were "approved instruments" in Canada.

Alcotest® is a registered trademark of Draeger Safety, Inc. The Alcotest® 7410 GLC and 6810 are each an "approved screening device" in Canada.

Datamaster®  is a registered trademark of National Patent Analytical Systems, Inc.  The BAC Datamaster® C  is an "approved instrument" in Canada.

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