Ethyl glucuronide, EtG, is a biomarker for recent alcohol use. The media has reported that individuals have been accused of abusing alcohol because of a positive EtG test result. Only to find out later that the individual was accidentally exposed to alcohol in a cleaning agent or hand cream. Similar to other drug test results, such as opiates and cannabinoids, if the cutoff is too low, a positive due to accidental exposure is difficult to rule out.
A number of years ago the cannabinoids test cutoff was 20 ng/mL to identify marijuana abuse. A number of instances were reported in the scientific literature of positives due to passive inhalation. The drug testing community responded by raising the cutoff levels to 50 ng/mL in order to rule out wrongly accusing an individual of marijuana abuse. Similarly, the opiate test cutoff was 300 ng/mL to identify opiates abuse. When it was identified that poppy seed containing foods might cause a positive opiates drug test, agencies such as the Department of Defense reacted by raising the cutoff to 2,000 ng/mL. Thus, individuals would not be wrongly accused of opiates abuse.
EtG is a biomarker of alcohol ingestion, but definitive data about a reliable cutoff to differentiate between alcohol abuse and accidental exposure is still under investigation.
Information in the scientific literature has reported that levels greater than 500 ng/mL are extremely unlikely to be caused by accidental exposure to alcohol. Hearsay information describes an individual who only used a hand sanitizer and tested positive for urinary EtG at a level of about 750 ng/mL.
Because of the concerns about accidental exposure to alcohol containing products, Ammon Analytical Laboratory has adopted a prudent approach to testing for urinary EtG.
The screening cutoff for EtG is 500 ng/mL. All positive EtG results are confirmed by an alternate scientific method, mass spectrometry. Thus, Ammon Analytical Laboratory provides a reliable means of identifying urinary EtG.
Similar to other laboratory tests a positive EtG result should be used as a sign. In this case a sign of alcoholic beverage consumption. Upon reporting the result to a physician further evaluation of the donor is important.
Post Written by: Jerry Meenan
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