Deceptive non-alcoholic beers
- Published: Jun 1, 2010
- Author: Steve Down
- Channels: Base Peak
The introduction of non-alcoholic beer was a welcome innovation by the brewing industry for several reasons. It allowed drinkers to experience the taste of beer without suffering from the effects of alcohol, which is a vital consideration for workers having a lunchtime tipple during work, or for drivers who are expecting to use their vehicles after drinking.
In the same way, it provided an alternative for people recovering from alcohol addiction or for those simply trying to cut down their alcohol consumption while still enjoying a drink.
For patients in alcohol treatment programs, or people in jobs where alcohol is banned completely, such as machine operators or drivers of public transport, their word is usually not regarded as sufficient evidence of abstinence. Instead, they can be placed on an alcohol testing regime during which they are expected to be clean over a long period of time.
The basis of testing programs is generally the detection of ethyl glucuronide (EtG) and ethyl sulphate (EtS), two established metabolites of ethanol which are universally accepted as markers of ethanol intake. The presence of EtG in urine samples above the general threshold level of 0.1 mg/L is regarded as a sure sign that the subject has not been steering clear of alcohol.
There are a few occasions where positive test results have been shown to be the results of other activities. They are still caused by ethanol but not by drinking it. For instance, there are published studies on the detection of EtG and EtS in the urine of people after rinsing with an alcohol-containing mouthwash or using a sanitising hand gel.
It seems clear that alcohol absorption into the body from other sources could also produce these two ethanol biomarkers. Sources such as medications, perfumes, hygiene products and goods like wine vinegar or soy sauce.
At least those people in testing programs can be confident about non-alcoholic beer. Or, can they? Well, not according to a new cross-border study within Europe, which studied non-alcoholic beers on sale in Germany. Here, ethanol can be present up to 0.5 vol.% before it must be declared in beverages, so small amounts may be present without the consumer being aware.
Annette Thierauf and colleagues from Freiburg University Medical Centre, Germany, the University Clinic for Psychiatry II, Salzburg, Austria and the University of Bern, Switzerland undertook to study the effects of non-alcoholic beer on two men and two women aged 23-30 years who were described as social drinkers.
After five alcohol-free days, they each ate a light lunch before drinking 2.5 litres of non-alcoholic beer over 3 hours. During the session they were allowed just one pretzel. The team tested the beer and found that it contained 0.41-0.42 vol.% ethanol, so was correctly marketed as non-alcoholic without any declaration on the labels.
Urine samples were collected regularly up to 20 hours after the beginning of beer consumption for testing. They were spiked with pentadeuterated EtG and EtS as internal standards and EtG and EtS were measured by LC/MS with electrospray ionisation using selected reaction monitoring. This procedure gave lower limits of quantitation of 0.05 and 0.04 mg/L for EtG and EtS, respectively.
The total amount of alcohol ingested during the 3-hour period was estimated to be 8.3 g, which the team described as the equivalent of one shot of hard liquor or 26 mL of a spirit containing 40 vol.% ethanol. In light of that, their results were not all that surprising.
Both EtG and EtS were found at high levels in urine. In three of the volunteers, the EtG concentrations ranged from 0.30-0.87 mg/L, maximising 3-5 hours after the start of drinking but remaining above the drug testing program cut-off value for about 17 hours. EtS levels were lower but still detectable at 0.04-0.07 mg/L for approximately the same period.
In the fourth subject, the high levels of both metabolites were not detected until about 17 hours after the drinking period, in the next morning urine but they were remarkably high at 14.1 and 16.1 mg/L for EtG and EtS , respectfully. This person denied taking any extra alcohol after the test period. The researchers were unable to explain this anomalous result and declared that further metabolic studies on this individual would be performed.
So, had these subjects been participating in an ethanol monitoring program, they would have tested positive with all the ensuing allegations and implications, despite their perceived abstinence.
The dangers of hidden ethanol in non-alcoholic beers and other consumer products are clear. Individuals entering alcohol abstinence treatment programs should be educated about the potential occurrence of ethanol in unexpected products such as "non-alcoholic" beer in order to prevent their exposure and subsequent failure during testing.
The views represented in this article are solely those of the author and do not necessarily represent those of John Wiley and Sons, Ltd.