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Argument for Accuracy in Hair Drug Testing

Hair is a poor medium for determining drug usage particularly when searching for cocaine metabolites.

Brief History:

The reported inventor of the technique to find cocaine in hair, Dr. Svetla Balabanova, reported in 1992 that she found cocaine in the hair of three-thousand-year-old Egyptian mummies that were in a German Museum. The find was remarkable because the plant that yields cocaine only grows in the New World, and pre-Columbian trans-oceanic trade had not been recorded in history. This was mystifying and created the need to repeat the tests and have other labs do confirmations as well. The procedure used was to first perform an immunoassay followed by “chromatography/mass spectrometry”.

The mass-media for the majority accepted this work and carried such articles titled, “Pharos on Crack” and “The Stoned Age”. The main focus of these articles was to try to explain the fact that cocaine was found. Some suggested a trans-Pacific route via the Silk Road to China while some speculated about unknown extinct plants that may have contained cocaine. Another group disputed the idea that cocaine was available in ancient Egypt and focused on the possibility the mummies were not genuine or that contamination was responsible.

Balabanova continued with her work and found more mummies testing positive for cocaine, some of them a millennium more recent that her previous group. No other published researcher was able to duplicate her discoveries and therefore, mainstream historians disregarded the discoveries, and the tenets of history regarding early trans-oceanic trade remained unchanged.

The fact that her work was not able to be duplicated allows us to believe that not all testing is infallible. All forms of testing and analysis must be able to show reproducibility and therefore reliability.

Factors that are Questionable:

Scientists have not yet determined if blood, sweat, or sebum is the depositing medium for depositing drugs in hair.

Should the analyte, if present, be there in larger quantities than in urine or blood specimens?

The hair sample must be washed. The washing sample may introduce contamination and has been considered controversial for a variety of reasons. These reasons are discussed further in the body of this document.

There is no liquefaction (procedure for making a solution from the hair sample) step. There are at least three different ways to liquefy hair. Comparative benefits and hazards do not appear to be clearly established.

Scientists have discovered that the relationship between levels of detected analytes and usage has not been established with hair tests.

Hair tests for drugs are closely related to hair tests for heavy metals (used for nutritional tests or environmental contamination tests). The medical establishment currently regards these tests as unreliable.

The Uncertainty of Hair Analysis for Trace Metals
Steven J. Steindel, PhD; Peter J. Howanitz, MD, JAMA (Journal of the American Medical Association) Editorial


Hair tests are not regulated, certified, nor accredited. Laboratory certification does not in itself guarantee a reliable test. The lack of certification for a lab test shows that the test has not reached that level of respectability. For urine testing, there are two nationally recognized FUDT Certifications: CAP (College of American Pathologists) and SAMSHA (Substance Abuse and Mental Health Services Association). Neither of these agencies give certifications for hair testing. CAP currently has nothing to do with hair testing and SAMSHA is developing guidelines for the procedure. If SAMSHA develops guidelines, one of the proposed guidelines is to require the test to be FDA approved.

SAMSHA currently is not certifying laboratories for drug hair tests.


Presently, urine is the only specimen collected for Federally regulated Workplace drug testing programs and for most private sector programs. Urine drug testing in the Federally related Workplace is currently recognized as the “Gold Standard” because of its proven accuracy, reliability, and fairness. This “Gold Standard” status is based on:

Use of Forensic Custody and Control Procedures from specimen collection to the final analytical procedure in the laboratory,

Exhaustive quality assurance procedures for both the initial and continuing certification of the laboratories in the National Laboratory Certification Program,

Analytical procedures to ensure no false positive results and minimize false negative results – Validity Testing,

Review of laboratory positives by a trained Medical Review Officer (MRO) for alternative explanations and as another quality assurance reviewer of the entire process

Procedures to ensure confidentiality of the donor throughout the process including the reporting of results to the intended recipient.

The Society of Forensic Toxicologists (SOFT) and the Toxicology Section of the American Academy of Forensic Sciences remain on record as not supporting hair testing for employee substance abuse programs due to lack of scientific knowledge, technologies and certification programs. . (David L Black, PhD., DABFT, DABCC, Director AEGIS Sciences Corporation, 2004)

Pathway of entry:

It is not clear by what mechanism drugs enter the hair. The sebum, blood or perspiration could be responsible for the delivery.

Gary L. Henderson, Martha R. Harkey, and Reese T. Jones


Current RIA (radioimmunoassay) techniques were developed for urine, which comes from inside the body. Hair is a different medium that can be contaminated by a variety of substances, and the potential for cross-reactivity of the test to other substances has been established. There should be an awareness that most commercially available RIA kits are designed for urine specimens, which is a liquid, and therefore have not been evaluated for possible matrix effects from different hair, which is considered a solid, digestion techniques or for cross-reactivity to other possible components in hair, such as cosmetics.

Cutoff levels:

On the drug tests that give results in terms of numbers, the results are usually given in a ratio of picograms per milligram or nanograms per milligram (pg/mg or ng/mg) of the analyte to the substance as a whole. This is considered the concentration of the analyte.

1 nanogram = 1/1,000,000,000 of a gram, a unit not likely to show up on any MSDS (Material Safety Data Sheet)


The cutoff level is a pre-designated concentration, above which the sample is declared positive, and below which is declared negative.

Currently there is no government established cutoff level with hair tests and different companies have varying levels of what is determined appropriate.


When cocaine is metabolized, it results in several higher metabolites in addition to the parent drug itself:

Benzoylecogonine (BZE)
Ecogonine methyl ester (EME)
Ecgonine ethyl ester
M-hydroxybenzoylecgonine (m-OHBZE)
P-hydroxybenzoylegonine (p-OHBZE)
N-desmethyl benzoyl ecgonine (norBZE)

Testing companies generally report results as positive and negative for Cocaine metabolites and if there is a positive, results are confirmed with GC/MS for a few of the metabolites: Benzoylecgonine (BZE) and Cocaethylene and simply Cocaine.
These results are reported in pg/mg with a generalized cutoff level of 300pg/mg which is, from the above reference, 3/1,000,000,000 grams.

Benzoylecgonine (BZE) is the most common tested-for metabolite with urine RIA tests. BZE s simply cocaine with a methyl group (-CH3) replaced with a simple hydrogen. In other words, BZE is cocaine with a part hydrolyzed, that is, reacted with water.
Chemical formula = C16H19NO4
Molecular weight = 289.326 g/mol

Cocaethylene is the ethyl ester of benzoylecogonine. It is chemically related to cocaine, which is the corresponding methyl ester. Cocaethylene is formed in the body when cocaine and alcohol have been taken simultaneously: the transesterfication is catalysed by carboxylesterases in the liver. It does not occur naturally in the coca leaves.
Chemical Formula = C18H23NO4
Molecular weight = 317.42 g/mol


Environmental Factors

1. Drug residue in the air from drugs that are smoke (marijuana, crack cocaine, heroin)
2. Persons, such as a hairdresser or a friend, that could have residue on their hands which could unwittingly contaminate a test subject’s hair.


1. Chemical treatments such as hair colorings and permanent curl or straightenings.
2. Shampoos, gels, and conditioning agents.

Stearic Acid (saturated fatty acid) molecular weight of 284.48
*Sodium Laureyl Sulphate (surfactant) molecular weight between 290-310
Isopropyl Myistate (emulsifier) molecular weight 270.46

*A binding compound and even posses the property to be absorbed into the skin.

These are common compounds found in nearly every type of hair shampoo, conditioners, lotions, and cosmetics for hair and some for skin.

The molecular weight of Benzoyleconine (BZE) is 289.326 which is noticeably in the same range as Sodium Laureyl Sulphate that has the property to be absorbed into the skin.

Disclaimer: While every effort has been made to ensure the accuracy of this publication, it is not intended to provide legal advice as individual situations will differ and should be discussed with an expert and/or lawyer.For specific technical or legal advice on the information provided and related topics, please contact the author.

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