Most people think nothing of driving down the road while consuming a Monster Energy Drink or a Red Bull. They think that because there is no alcohol in these drinks, it could have no ability to impact their breath tests. Unfortunately, the scary reality is that many energy drinks do contain trace concentrations of alcohol that can produce false positive readings on breath tests.
Mouth Alcohol Effect and the 15-Minute Rule
Breath test results can indeed be falsely elevated by energy drinks, and a 15-minute mouth alcohol deprivation period is required to eliminate this effect. Research has shown that, despite not being classified as alcoholic beverages, many energy drinks contain low concentrations of ethanol, which can lead to a brief “mouth alcohol effect” on breathalyzers.
Study Shows Prevalence of Ethanol in Energy Drinks
A study titled “Potential Effect of Alcohol Content in Energy Drinks on Breath Alcohol Testing” by Lutmer, Zurfluh, and Long (2009) investigated this phenomenon. They found that 88.9% (24 out of 27) of the energy drinks tested contained detectable levels of ethanol, with concentrations ranging from 5 to 230 mg/dL. This prevalence and concentration were notably higher than previously reported for other non-alcoholic soft drinks; for instance, 13 out of 27 energy drinks (48.1%) had ethanol concentrations above 0.06% w/v, and 9 were even higher than 0.096% w/v, which was a significant increase compared to earlier findings for soft drinks.
Impact of Consumption on Breath Test Results
When volunteers consumed between 24.6 and 32 ounces of these energy drinks, 11 out of 27 (40.7%) beverages produced positive readings on a portable breath-testing instrument when samples were taken within 1 minute of finishing the drink. These initial positive results ranged from 0.006 to 0.015 g/210 L. A statistically significant correlation was observed between the ethanol concentration in the drink and a positive breath alcohol test result above the lower limit of detection (P < 0.01), with no beverage below 64 mg/dL ethanol causing such a reading.
False Positives Are Temporary and Avoidable
However, the key finding regarding false elevation is its temporary nature. All breath tests conducted using a portable breath test, DataMaster, and Intox EC/IR II instruments yielded alcohol-free readings (0.000 g/210 L) when taken at least 15 minutes after the completion of drinking. This demonstrates that the initial positive readings are due to mouth alcohol, which disperses rapidly. The study also clarified that energy drinks do not contain enough alcohol to be absorbed into the bloodstream and cause a measurable blood alcohol content (BAC); for example, consuming around 200 ounces of an energy drink with 0.23% w/v ethanol would be required to reach even a 0.02 g/dL BAC. Even when mixed with alcoholic drinks, the inherent ethanol content of energy drinks has a negligible impact (less than 1%) on calculated BAC.
Recommendations for Accurate Breath Testing
Therefore, to prevent false-positive readings, the study concludes that it is crucial to afford subjects a minimum 15-minute observation period prior to any breath-alcohol testing. This is particularly relevant in contexts where such observation periods might not be strictly mandated, such as in the IRP scheme.
