Hair follicile testing

Often the most important part of drug testing is deciding what type of drug test to conduct. You must ask yourself, “What ‘question’ am I asking this donor?” The question may be “Are you impaired?” or “Do you have a habit of drug use?” By thinking in terms of the question you need to answer, you can select the appropriate testing method for the situation.

When you need to know if there has been recent drug usage or if the donor is currently impaired, urine testing is recognized as the industry standard. When the question is “Does this person have a habit or pattern of drug use?,” hair testing is fast becoming the test of choice. Using a small sample of hair cut at the crown of the head, hair analysis evaluates the amount of drug metabolites embedded inside the hair shaft over a longer timeframe, with the standard test going back 90 days. The test result can also be used to determine approximate usage levels of the drug.

The standard 90-day hair test uses an inch and a half of hair from the head. If head hair is not available, then body hair can be tested, showing a broader range of approximate-ly twelve months of detection. It is extremely important to understand that Hair-testing does not detect the most recent 1-2 weeks of drug use because the hair has not grown out from scalp, for more immediate usage of 7-10 days urinalysis is recommended.

Standard hair-testing cutoff levels are designed to catch repeat drug abusers, while urinalysis cutoff levels are more sensitive and can detect trace drug usage. The question of external contamination creating a “false positive” test result is not a concern since hair testing is a metabolite-based process. Like urinalysis, hair testing reports levels of drug use making it applicable to rehabilitation programs where patterns of past drug use are reviewed.

The standard 5-Panel hair test mirrors that of other testing methodologies. It screens for Cocaine, Marijuana, Opiates (Codeine, Morphine & 6-Monoacteyl Morphine), Amphetamine, (Meth/amphetamine & Ecstasy), and Phencyclidine (PCP). Several other drug panels are also being analyzed in hair, including Oxycodone, Hydrocodone, and Hydromorphone. While urinalysis offers drug panels not currently found in hair, many new panels are being developed for hair analysis.

Hair testing is prevalent in industries where there is a high level of concern for health and workplace safety, such as heavy manufacturing or food service industries. Since hair testing is a quick and easy observed collection, sample substitution is impossible to do without cooperation of the sample collector. In addition, hair testing results cannot be altered with the use of shampoos or other external chemicals. These elements have aided in its ability to withstand legal challenges, gaining wide court support for hair analysis.

Hair Follicle Drug Testing FAQ

What is hair drug screening?

 
What is hair drug screening?
A hair screen is an examination that uses a small sample of hair to identify specific drugs used by the person being tested. A hair follicle drug test measures the drug molecules and their specific metabolites that are produced only after the drug has been processed by the human body. After the drug is processed, trace amounts of its metabolites are inserted into hair follicle by the bloodstream.

What time period does a standard hair follicle test cover?
A standard hair follicle screen covers a period of approximately 90 days, but is susceptible to time variation depending on the growth rate of your hair. The hair sample is cut as close to the scalp as possible and the most recent 3.9cm (or 1.5 inches) are tested. It is possible to go back even further than 90 days since the time period is limited only by the length of the hair sample, but is standardized to a 90 day history.

What type of drugs can be detected in a standard hair test?
Cocaine (Cocaine & Benzoylecgonine), Marijuana, Opiates (Codeine, Morphine & 6-Monacteyl Morphine), Methamphetamine (Methamphetamine/Amphetamine & Ecstasy), and Phencyclidine (PCP). These five drug classes are mandated for testing by the Federal Government.

How fast does head hair grow?
Hair collected at the crown of the head grows on the average of approximately 1.3 cm (or 1/2 inch) per month. This growth rate varies among people by approximately + .2 cm per month which can create a possible time variation of up to +1 week per month.

Can body hair be drug tested like hair from the head?
Body hair can be drug tested just as hair from the head. The growth rates for body are considerably slower than the hair from your head. Most body hair is replaced in about one year. It is challenging to precisely represent the time period of a standard screen with body hair so substances may be detected in body hair for up to 1 year after the substance left the blood stream.

How much hair is needed?
A standard screen with GC/MS confirmation requires 40+ milligrams of hair or approximately 50 – 70 strands that are up to 3.9cm (or 1.5 inches) in length. The thickness and pigment color of different types of head hair (thick black vs. thinning gray) is the basis of this variation.

What if I am almost bald or have no hair?
Hair can be collected from several head and/or body locations (excluding pubic areas) and combined to obtain the required amount of hair. In the rare case where no hair is collectable, complete urine/adulteration testing may be utilized.

How effective is hair follicle testing in detecting drug usage?
In comparison to a urinalysis drug test, cocaine, PCP, opiates, and methamphetamine have proven hair analysis far more effective than urine testing in identifying low-level drug use over an extended period of time since these are normally out of the bloodstream in within 3-7 days. The detection of marijuana is currently less sensitive than the other drugs in identifying low level drug users, but is considered approximately equal to urinalysis in identifying marijuana users. The detection period for hair is limited only by the length of the hair sample and is approximately 90 days for a standard screen.

How do drugs get into hair?
After a substance is ingested, whether orally, smoked, snorted, or injected, metabolites are produced as the drug is processed by the human body. As these drugs and metabolites circulate in the blood stream, they enter and nourish the hair follicle and are then inserted into the hair strand.

Hair Testing Questions & Answers

Q. What is Hair Screening?

A. A State-of-the Art method for detecting drugs in hair using enzyme-immunoassay (EIA). EJA measures the drug molecules permanently entrapped in the hair which were incorporated following ingestion.

Q. What drugs are included in a standard Hair screen?

A. Cocaine, marijuana, opiates, methamphetamine, and phencyclidine (PCP). These drugs were identified as “illegal drugs” in The President’s Executive Order 12564 and are the five drugs mandated for testing by the Federal Government.

Q. What time period does a standard test cover?

A. A standard screen covers a period of approximately 90 days. The hair sample is cut as close to the scalp as possible and the most recent 3.9 centimeters are tested.

Q. How fast does head hair grow?

A. Studies indicate that hair collected at the crown of the head grows on the average approximately 1.3 cm (or 1/2 inch) per month. this growth rate varies among people (estimated at ±.2 cm per month (iSO), consequently the same 3.9 cm length of hair can represent different time periods.

Q. How much hair is needed?

A. A standard screen with GC/MS confirmation requires 20 milligrams of hair or approximately 60 strands.

Q. How does Hair Testing compare to urinalysis?

A. The primary difference is the wider window of detection with hair. Cocaine, methamphetamine, opiates and PCP are rapidly excreted and usually undetectable in urine 72 hours after use. The detection period for HAIR is limited only by the length of the hair sample and is approximately 90 days for a standard screen. Additional advantages include non-intrusive collection procedures, virtual elimination of test evasion; greater accuracy through test repetition capability. The combination of an increased window of detection and resistance to evasion makes HAIR far more effective than urinalysis in correctly identifying drug users.

Q. How soon after use can a drug be detected in hair?

A. It takes approximately 5-10 days from the time of drug use for the affected hair to grow above the scalp.

Q. What is the shortest time period that can be accurately evaluated?

A. In most situations the minimum time period is approximately one month. Due to variability of hair growth rates, EIA cannot go back in time to determine if an individual used drugs on a particular day or week.

Q. Can tests be run on people with little or no hair?

A. Yes, hair can be collected from several locations on the head and combined to obtain the required amount of hair. In addition, body hair can be used as an alternative to head hair.

Q. Does body hair give the same type of results as head hair?

A. Yes, body hair can be used to test for the five standard drugs. Body hair growth rates are considerably more variable and slower than head hair. Most body hair is genetically controlled and replaced within one year. Therefore, it is difficult to accurately represent the time period of a standard screen with body hair.

Q. Can hair collected from a brush be used?

A. No, the Testing Lab requires a hair sample to be collected using proper chain-of-custody protocols that will withstand a legal challenge. The Testing Lab requires that the sample be submitted with Sample Acquisition Materials. The test subject must initial the sample to certify the authenticity of the sample at the time of collection.

Q. How does the Testing Lab establish its cut-off levels?

A. Cut-off levels are established by the minimum detection levels for GC/MS confirmation.

Q. What are the differences between Hair cut-off levels and urinalysis cut-off levels:

A. In general, cut-off levels for urinalysis have been established to reduce the possibility of an evidential false positive due to passive inhalation. A true comparison of Hair/urine cut-off levels is impossible, since the time frame differs (90 days vs. 3 days). SAMHSA’s (NIDA’s) recommended cut-off levels for forensic urinalysis tests are expressed in nanograms per milliliter (ng/ml) of urine. HAIR cut-off levels are expressed in nanograms per milligram (ng/mg) of hair.

Q. Does the Testing Lab perform GCMS confirmation of all positive Hair results?

A. The Testing Lab provides automatic confirmation for ALL specimens that screen positive screen (opiates, PCP, methamphetamine, cocaine and marijuana).

Q. Can Hair be affected by cross-reacting substances such as over-the-counter medications?

A. Enzyme-immunoassay antibodies (EIA), similar to those used to test urine, are used for the initial screening test for drugs of abuse in hair; therefore the potential for substances such as over-the-counter medications to cause a false positive screening result does exist. To eliminate the possibility of reporting a false-positive due to cross-reactivity, the Testing Lab automatically confirms by GC/MS all positive results for methamphetamine, opiates, PCP, cocaine and marijuana.

Q. How effective is Hair Testing in detecting drug users?

A. In side-by-side comparison studies with urinalysis, the cocaine, PCP, opiates, and methamphetamine assays have proven hair analysis far more effective than urine in identifying low-level drug use. The marijuana screen is currently less sensitive than the other drugs in identifying low level drug users but is considered roughly equal to urinalysis in identifying marijuana users.

Q. Does external exposure to certain drugs, like marijuana or crack smoke, affect the HAIR results?

A. ALL hair samples that produce a positive screening result are washed extensively to remove external contamination and re-screened for the potential positive drug. If the secondary HAIR screen is positive and the ratio of the wash solution is greater than 10% of the confirmation result, the Testing Lab will consider this sample contaminated. If the ration of the wash solution is less than 10% of the confirmation result, the Testing Lab will consider the sample as positive. Marijuana does not follow the wash patterns of the other drugs. To rule out the possibility of external contamination for marijuana, the Testing Lab exclusively detects ONLY the metabolite (THC-COOH) which is only produced by the body and cannot be an environmental contaminant. In addition, the Testing Lab will NOT analyze pubic hair for the presence of the THC-COOH metabolite.

Q. Does treatment of the hair affect test results?

A. Commonly used hair products (e.g. shampoos, conditioners, sprays, mousses and gels) have no significant effect on Hair results. In fact, normal hair washing helps to remove external contamination. Extensive bleaching, perming and dyeing may damage the protein matrix of hair allowing a portion of the drug from the hair to be extracted, lowering the final quantitative result with certain drugs. Treated hair can be readily identified from the wash ratios and/or staining procedure. Treated hair results will be reported indicating that the correlation between the extent of drug use and the quantitative result were affected.

Q. Is the Testing Lab’s internal chain-of-custody comparable to a urinalysis laboratory.

A. The Testing Lab’s internal chain-of-custody is modeled after the requirements in the SAMHSA (NIDA) guidelines.

Q. What is done with the excess hair that is not tested?

A. The hair not used from the time period being tested (i.e. three months equals 3.9 cm) and all remaining hair is stored in the chain-of-custody sample acquisition pouch. Negative hair is stored for one month. Positive hair is stored for one year.

Q. How long are positive and negative test result reports kept on file?

A. All laboratory records and test results are kept for a three year period.

Q. Has the Testing Lab had to defend hair analysis in a lawsuit filed by an employee or applicant?

A. The Testing Lab has worked closely with customers who have been challenged or named in lawsuits based on action taken from positive hair analysis results. To date, based in part on the Testing Lab’s chain-of-custody documentation and ability to provide valid and reproducible re-tests, all threats or lawsuits were dropped.

Q. What experience does the Testing Lab have providing Expert Witness Testimony?

A. The Testing Lab’s forensic experts have qualified as expert witnesses in Ohio, New York State, California, Texas, Nevada, Alabama and Arizona in over 250 civil, criminal, and Superior Court trials.

Q. What other drugs are available to be tested in hair analysis?

A. Currently, nicotine, methadone, simple benzodiazepines, tricyclic antidepressants, assays and mescaline have been detected in hair. However, many details such as cutoff levels and dose response relationships have not yet been established for these compounds.

Q. What is the basis of the racial bias claims for hair analysis?

A. Racial bias suggests that different racial groups will incorporate drugs into hair at a different rate as compared to another racial group (Caucasian vs. black African). Hair color is determined by the amount of pigment (melanin) contained in the shaft. Drugs are believed to bind to melanin in a different manner than other cellular structures in the hair.

Q. How do drugs get into hair (what is the basis of hair analysis)

A. As drugs circulate in the blood stream, they enter and nourish hair follicle cells. As cells grow, they trap the drug molecules within the hair cells and are eventually “sealed” in the keratinized hair shaft. Thus, the amount and time the drug(s) are in the blood stream is proportional to the amount of drug detected in the hair.

Q. What is external contamination?

A. Drugs that are deposited on the hair shafts by any means (dust, sweat, combs, etc.) are considered external contaminants. These contaminants must be removed prior to the testing being performed.

GLOSSARY OF TERMS

Abnormal Wash Ratio (AWR)

Terminology for samples showing an inconsistent relationship of drug detected in the wash as compared to drug detected in the hair sample. AWR samples can be caused by heavily damaged, treated or contaminated hair and may require additional testing.

Chain-of-Custody

Protocol established to maintain integrity and confidentiality of all samples submitted. Chain-of-Custody begins with the collection procedure but must be maintained throughout shipping, testing, result reporting and record/specimen storage.

Gas Chromatography/Mass Spectrometry (GC/MS)

Highly specialized method of analysis used to detect presence of substances in a specimen. GC/MS is considered the “Gold Standard” and represents “state of the art” technology.

Parent Compounds & Metabolites

All drugs are taken into the body, utilized and then broken down into compounds known as “metabolites.” The original substances are referred to as “parent compounds.”

The following are a few examples:

Parent Compounds Metabolites
Cocaine Benzoylecgonine
THC (Marijuana) Carboxy-THC
Methamphetamine Amphetamine
Heroin/Morphine/Codeine Morphine/Codeine

 
Process of cleansing unrelated matter and chemicals from the hair sample prior to testing. This procedure eliminates traces of external contamination from the hair sample. Portions of each wash are saved in case a sample tests positive at which time the ratio of the drug found in the wash will be compared to the ratio of the drug found in the hair.

Window of Detection

The period of time that a particular test correlates to. This time frame is dependent on the length of the hair sample tested. On the average, hair grows at a rate of 1.3 cm (about .5 in) a month. The EIA Standard Screen requires 3.9 cm (about .5 in) and will detect drug usage over an approximate 90 day period.