Q&A - Mouthwash & Roadside Alcohol Testing

Counter Attack LogoYesterday, over a 6 hr. span, my husband had consumed 4 cans of beer, and 2  5oz glasses of 11.5% white wine, with lots of ice.  My husband is 165 lbs. He had an 8 hr. sleep. He woke up in the morning, did his usual coffee, shower, shave, etc. ( 1hr. total)  he then brushed his teeth, and gargled with his mouthwash.  He then left for work, and 10 minutes later, there was a roadblock at 7:30 a.m.  The officer smelled alcohol.  He was given a breathalizer, and it blew WARN. He was given a 3 day IRP, and vehicle impounded for 3 days.

Now my question for you is this:  He had 6 drinks over 6 hours, and there was a total of 9 hours lapping before the test.  Should the alcohol not have been out of his system?  After thinking about it, I thought maybe it was the mouthwash.

I  did some research, and it says that mouthwash can elavate and increase your mouth alcohol level.  Our mouthwash is 26% alcohol. (SCOPE OUTLAST 5x longer was the brand) Is it possible that 10 minutes after rinsing with mouthwash could it have caused mouth alcohol, and therefore gave a false reading?  And if so, what can we do about it?



Yes, mouthwash can affect breath tests and screening device users learn about it as part of their training. Typically I provided mouthwash when training officers in the use of the device and the students practiced with it on each other. One would rinse their mouth and then keep it closed, no talking or eating etc. and periodic samples would be taken to see how long it took to not produce a reading. The other would rinse, and then talk while the other repeated the tests.

At the time, we were to observe a 10 minute waiting period and try to have conversation with the driver if we had any suspicion that there was a recent drink or in this case, recent mouthwash (or any other alcohol containing liquid) use. Generally by then the alcohol present in the mouth would have dissipated and not affect the reading.

I have also written on how long it takes to sober up here in the forum.

The blue copy of the IRP form that your husband was given has a set of instructions on the back that tell you how to go about having the prohibition reviewed.

Submitted by E-mail

He was offered another test, but he didn’t take it, because we didn’t know about the mouthwash.  I think the officer should have suggested he take a second test, instead of asking him, as well as stating that the lower number would prevail, and my husband would have taken it.

We could ask for a review, but I feel without a second test, chances of him winning would probably be slim, at a cost of another hundred dollars.  This has been an educational lesson.

Counsel on Second Sample

The Acumen Law Corporation blog contains an article on demanding a second sample at roadside. Their counsel, valid at this time and subject to change if the laws change, is that the driver should always demand a second sample. The lowest reading of the two would apply and there is no downside for the driver in making this demand.

Police in BC advise a driver who has blown a warn or fail reading of the following:

In accordance with the Motor Vehicle Act, I am informing you that you have the right to a second test by providing a second sample of breath into a different Approved Screening Device.

You must request the second test forthwith and prior to the service of your Notice of Prohibition.

By legislation the lower of the two test results will prevail.

Do you understand?

Would you like to provide a breath sample?

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