United States Drug Testing Laboratories (USDTL) launched two new tests for monitoring long-term alcohol exposure on Friday. Using fingernail and hair specimens, the new assay is the first and only test to report a donor's alcohol exposure for the past 90 days reliably.
The NailStat and HairStat® EtG tests measure ethyl glucuronide (EtG) in fingernails and hair samples. EtG is a minor product of alcohol metabolism and is therefore a direct alcohol biomarker. A USDTL study sponsored by NIAAA of 600 college students showed that EtG levels in nails and hair related extremely well to the number of drinks reported.
"For the first time, we have a tool that provides direct evidence of alcohol exposure with an approximate dosing history," said USDTL President and Scientific Director Douglas Lewis.
Previous alcohol tests, such as blood phosphatidylethanol (PEth) and urine EtG, did not provide a large enough exposure history for many healthcare professionals monitoring abstinence or level of exposure. PEth tops out at three weeks prior to collection in blood samples, while urine only provides a few days at best using EtG analysis. EtG in hair and nails has the best timeline follow-back history of any alcohol assay, using LCMSMS high sensitivity methodology.
"Nail samples are the preferred specimen over hair samples since fingernails show no gender bias," said Lewis. "Because cosmetic treatments destroy the presence of some drugs and biomarkers in hair, many women are not able to provide a valid sample."
USDTL developed the tests for practitioners who are interested in a clinical diagnostic when alcohol may contribute to a health condition. USDTL tested nail and hair EtG through two Small Business Innovative Research (SBIR) grants from the National Institute on Alcohol Abuse and Alcoholism (NIAAA). NIAAA has long sought accurate, objective measures of alcohol exposure that would be available to researchers, clinicians, courts and businesses.