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Wrongful Termination: Cocaine in Hair

Sampling procedures, collection procedures and testing procedures should all be evaluated when there is a question in the results.

I have been provided material for the above-referenced case in confidence by Pamela Carter of the Carter Law Group located in New Orleans, LA. Upon review of the above-referenced case material, I have the following findings:

1. The units of measure and the cut-off limits are different between Psychemedics and Quest Diagnostics Laboratories.

a. Unit of measure for Psychemedics Laboratories is ng/mg with a cut-off limit of 5ng/mg.
b. Unit of measure for Quest Diagnostics Laboratories is pg/mg with a cut-off limit of 300pg/mg.
i. Note that 1pg=1000ng

2. The hair test from Psychemedics with lab ID no. 116713882 listed a positive cocaine result of 15.4ng/mg and a positive Benzoylecogonine (BZE) of 0.3ng/mg on 10/11/2010.

a. Mr. Client requested in writing that this sample be reevaluated and the results of the re-run of the original extract listed a positive cocaine result of 18.5ng/mg and a positive BZE of 0.4ng/mg of on 11/4/2010.

3. On or about 11/12/2010, approximately 38 days following the collection of the hair sample collected for analysis at Psychemedics, Mr. Client had an independent hair test at Quest Diagnositics.

a. This sample was photo ID verified and was accessioned under the no. 685661S.
b. This hair sample was negative for cocaine and it’s metabolites.

4. The hair media collected for Psychemedics analysis was armpit hair.

5. The hair media collected for Quest Diagnostics analysis was mustache hair.

6. No clear indication was presented regarding the collection body, DISA or representatives of DISA for collection of the hair samples, used clean implements or changed gloves for each individual sample collection.

7. The average rate of growth as listed by Toxicology Associates Hair Analysis Testing website is:

a. Armpit = approximately 12mm or 1.2cm of growth per month.
b. Mustache = approximately 9m or 0.9cm of growth per month.

8. A study of known cocaine users in treatment demonstrated over 10 subjects that a heavy user of cocaine would likely test positive for cocaine in hair at or about 6.4-19.2ng/mg and would likely test positive for BZE in hair at or about 0.3-2.5ng/mg. (Cone 1991)

9. A study of known cocaine users in treatment that used approximately 1-3 times per week demonstrated over 6 subjects that this moderate user would likely test positive for cocaine in hair at or about 0-5.7ng/mg and would likely test positive for BZE in hair at or about 0-1.1ng/mg. (Harkey et. al. 1991)

10. A controlled study performed where 25 subjects were given doses of cocaine ranging from 0.6-4.2mg/kg tested positive for cocaine in hair at or about 0.1-5ng/mg and tested positive for BZE in hair at or about 0.1-.36ng/mg.(Henderson et. al. 1993).


External contamination or mislabeling of samples either collected or analyzed cannot be eliminated in these findings for the case of Mr. Client. It is unusual for results of hair testing within approximately 38 days, even though the hair was collected from different regions of the body, to have rendered such different results. Hair growth rate can vary amongst individuals by 0.5cm to 1.5cm per month. Increasing doses of cocaine ingested generally result in increased levels of detectable cocaine and it’s metabolites in hair, however a clear dose relationship has not been established. (Welch 1995)

A study conducted of a small amount of external contamination resulted in a concentration of >1ng/mg and a moderate BZE level generally <0.5ng/mg still being detectable in hair for up to 10 weeks following contamination. These results question the reliability of hair testing. In fact, even with the most sophisticated decontamination procedures, it is not possible to distinguish a contaminated specimen from a specimen from an active user. (Romano et. al. 2001)

A controlled study of hair ranging in color from blonde to dark brown/black from five subjects was performed. The hair samples were contaminated with cocaine HCL and treated with synthetic sweat for purposes of evaluating the efficacy of hair testing and the industry’s decontamination procedures. This study, conducted by RTI (Research Triangle Institute), involved sending samples to independent laboratories and analyzed by RTI. Only one hair sample analyzed that was decontaminated within one hour of exposure yielded negative results for cocaine and its metabolites. The balance of the hair samples were shampooed daily for 10 weeks. From approximately 21 days post contamination until the end of the study, the mean BZE to cocaine ratio for all hair types exceeded 0.05ng/mg, the proposed federal mandatory guideline requirement. None of the decontamination procedures or strategies used was effective at removing all of the contamination. Some of the contaminated hair samples from this study would have been reported as positive for cocaine use based on the federal mandatory guidelines. (Stout et. al. 2006)

By 3rd Degree Investigations, Inc.
Chemistry Forensic Consultant and Expert Witness
Dana Way started her career working in a laboratory in 1989. While working as a Chemist for Commonwealth Laboratories and later for Roche Analytics Laboratories, she learned analysis and reporting, laboratory methods and procedures, method development, and worked with a variety of analysis instruments. Dana started a company called 3rd Degree Investigations in 2005. Since then her work as a defense expert has sent her across the country where she has testified in both state and federal criminal and civil courtrooms. Additionally Dana has acted as a consultant for federal and state law enforcement agencies.

Copyright 3rd Degree Investigations, Inc.

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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