via Reliability of hair drug tests up for debate

The Birth of Junk-Science in Drug and Alcohol Testing

The attached article concerns the reliability of hair-strand tests routinely accepted in child welfare cases in Ontario   as evidence of parental drug or alcohol abuse.  A positive test can lead to loss of parental custody of children.

The risk for false-positive results appears to be higher in women because of the higher use of alcohol-based hair products and the limitations of these tests are addressed in the article.

Almost 98% of ingested alcohol is eliminated through the liver in an oxidation process that involves its conversion to acetaldehyde and acetic acid, but the remaining 2% is eliminated through the urine, sweat, or breath.¹

Ethyl Glucuronide (EtG) was introduced in 1999 as a biomarker for alcohol consumption,² and was subsequently suggested as a tool to monitor health professionals by Dr. Gregory Skipper, M.D.,  because of its high sensitivity to ethanol ingestion.³

This minor metabolite of alcohol was reported by  Skipper, M.D. and Friedrich Wurst, M.D., in November 2002 at an international meeting of the American Medical Society, to provide proof of alcohol consumption as much as 5 days after drinking an alcoholic beverage, well after the alcohol itself had been eliminated from the body.

In his study Dr. Skipper arbitrarily chose a value of 100 as a cut-off for EtG. The rationale behind this value is not cited.

In 2003, because of these and other reportedly remarkable results (e.g., positive findings, confirmed by admissions by the tested individuals, after traditional urine tests had registered negative), Skipper pitched the test to National Medical Services, Inc. (NMS labs) and it was developed as a Laboratory Developed Test (LDT).

So began EtG testing began in the United States, and this paved the way for the hair tests described. The urine EtG test introduced by Skipper is the index case and prototype for an array of unproven forensic tests introduced to the market as LDTs.