MROs are considered to be the gatekeepers of the workplace drug-testing process. As such, quality control is an ongoing major concern for the MRO, and written protocols, or standard operating procedures (SOPs), that are followed in the review and interpretation of each result are essential. The DOT regulations and the MRO training manuals from the American Association of Addiction Medicine (ASAM) and American College of Occupational and Environmental Medicine (ACOEM) are excellent models and establish high standards of practice.
Adequate documentation is necessary for each case, and standard forms or templates to be filled out and used to document review activities are excellent tools. If there are multiple MROs in the same practice, a process of documented peer review should be ongoing. Non-physician staff under the direct supervision of the MRO perform many administrative and data management tasks. For example, under DOT rules, staff members can review and release laboratory-negative results. The staff reporting the result to the employer may use an MRO name/signature stamp and initial and date the test result prodding his/her name as the staff member reporting the result. The MRO must personally review 5% of all the negative results as a quality control measure. This 5% review must also include review of results requiring corrective memoranda.
Quality control for laboratories is defined in Subpart F of Part 40, and most of that is internal. MROs, however, become involved with the requirement in DOT and DHHS regulations for blind specimen submissions to the laboratories. Under DHHS rules, the federal agencies must submit 3 blind specimens to the laboratory for every 100 employee specimens submitted. For DOT, large employers and third party administrators (TPAs) (those conducting testing on more than 2,000 covered employees) must submit blind specimens to the laboratory at a rate of 1 per 100 employee specimens. Seventy-five percent of the submitted specimens must be blank (contain no drug nor be adulterated or substituted), 15% must contain a known drug, and 10% must be adulterated or substituted.
Blind specimens must be indistinguishable to the laboratory from any other specimen, and as such will be reported to the MRO as will any employee specimen. Federal CCFs must be used and the blind specimens must be submitted as split specimens. The MRO should match the result from the laboratory with the known contents of the blind specimen, maintain a file on the laboratory’s performance, and report any “False positive” blind specimen results to the DHHS and/or DOT. Blind specimens may be obtained from several suppliers that are listed on the SAMHSA Workplace Programs website.
The MRO is also involved in situations where a donor is unable to provide a urine specimen for a federally required drug test. If an employee cannot produce the required urine volume of 45 mL for a DOT drug testy after being offered fluids to drink and 3 hours’ time to provide the specimen, the donor will he required to undergo a medical examination by a physician. The employer consults with the MRO in identifying a physician to conduct the examination (preferably as soon as practical after the “Shy bladder” incident). Regulatory guidance states that the physical examination must determine whether or not “a medical condition has, or with a high degree of probability could have, precluded the employee from providing a sufficient amount of urines”. MROs should consult with the examining physician and develop guidelines for the shy bladder evaluation. During this consultation, the MRO must tell the examiner that the employee was required to take a DOT drug test, but was unable to provide a sufficient amount of urine to complete the test, and the consequences of refusing to take a required drug test. Under DOT rules, a medical condition includes an ascertainable physiological condition (Eg: a urinary system dysfunction) or a medically documented preexisting psychological disorder, but does not include unsupported assertions of “situational anxiety” or dehydration. It is clear that the MRO, not the physician conducting the medical examination/evaluation, is responsible for making the final test result determination and reporting it to the employer in writing. The examining physician provides his/her findings to the MRO in writing and the MRO then determines if the test is canceled due to a medical explanation for the shy bladder or is a “Refusal to test” because there is no medical explanation for the donor’s inability to provide a urine specimen.
Thus far, this chapter has focused on the MRO role in the review and interpretation of urine drug test results, with particular emphasis on the federal (DHHS and DOT) regulations. Increasingly, workplace programs in the non-federal arena are using other specimens and other methodologies for detecting and deterring illicit drug use. This section provides a brief overview of alternative specimens used in workplace drug testing and describes the MRO role in the review and interpretation of these results.
Hair, oral fluid, and sweat have been used for forensic testing for many years. The development and refinement of the use of these specimens for forensic drug testing is well underway and continuing. SAMHSA recognition of the state of the science in alternative specimen drug testing came with the release of the Notice of Proposed Revisions to the Mandatory Guidelines for Federal Workplace Drug Testing Programs (69 FR 19673), April 13, 2004. These were withdrawn from the process of becoming a Final Rule on June 30, 2006, but still remain available from SAMHSA and on the SAMHSA website as proposed guidelines.
Even though not used in federal drug-testing programs, the technology of testing alternative specimens for drugs is well-advanced and industry acceptance of this testing is widespread. Several testing laboratories have pursued and received FDA clearance for hair and oral fluid assays for the 5 drugs contained in the HHS 5 testing panel.
The role of the MRO is the same in reviewing confirmed laboratory results for alternative specimens as it is for reviewing confirmed urine findings. As with urine, all donors with nonnegative laboratory results should be given a chance to speak with the Medical Review Officer. The MRO should ask ‘Is this demonstrably the donor’s specimen? Is the chain of custody intact? Has the lab tested appropriately? Is there a legitimate medical explanation for the confirmed lab finding? Does the donor request a reconfirmation process?’
MROs are advised to openly discuss the benefits and controversies of alternative specimen testing with any employer considering doing this type of testing. Review of alternative specimen results by the MRO does not necessarily mean that the MRO endorses the testing itself, and should be restricted to establishing the presence or absence of a legitimate medical explanation for the confirmed lab finding. Action based on the result is completely the responsibility of the employer.
Also, many states define specimens that may be used for testing within that state, and in some cases prohibit the testing of some or all alternative specimens. In the realm of non-federal drug testing it is essential that the MRO be knowledgeable about the applicable laws of the state in which employers conduct their testing programs.
Hair testing can be completed for almost any desired analyte, but commonly forensic drug testing is restricted to the HHS 5 drugs. FDA clearance has been granted several laboratories at this writing for these 5 drugs. Hair may be collected from any part of the body, but head hair is clearly the preferred collection area. Some employers restrict collection to the head, but many recognize that head-shaving and alopecia are common, and allow collections from other parts of the donor’s body. Hair growth rates are different for different body parts, and should be taken into account by the MRO when comparing specimens from the same donor collected from different body areas. Below is a chart of relative hair growth rates in mm/day:
- Scalp crown 0.35
- Vertex 0.44
- Beard 0.27
- Chin 0.38
- Eyebrow 0.16
- Axilla 0.30
- Chest 0.40
- Thigh 0.20
Workplace convention is to collect and test a 1-cm by 3 cm (100 mg) specimen of crown hair, and therefore the window of analyte detection is considered to be 90 days. Clearly if the collector cut a specimen that is 2 cm by 2 cm there is a different window of detection, and that donor will have a different drug test than will the donor who gave a 1-cm by 3-cm specimen. Laboratories cut longer specimens to the correct measurement before testing.
As with urine, hair specimens are screened and confirmed. Analyte quantities are much smaller and results are reported in units per mass rather than units per volume. Below is a table of common screening and confirmation cutoffs currently in use:
- Cocaine 5 ng/10 gm
- Amphetamines 5 ng/10 gm
- Opiates 5 ng/10 gm
- PCP 3 ng/10 gm
- Marijuana 2 ng/gm; confirm 1 ng/gm
Results may also be reported in pg/mg units. Confirmation is usually done by liquid chromatography tandem mass spectrometry because of the small quantities of target analytes.
Although it is gaining wider acceptance in the workplace drug-testing world, hair testing remains to some degree controversial. The main areas of controversy are the potential for racial (or more correctly stated hair color) bias and ambient air contamination of the hair that may produce a false positive. Here is a brief synopsis of each controversy, and the reader is encouraged to research further before coming to any conclusions.
Several studies have shown that deposition of drug in hair is increased in hair with a higher concentration of melanin. Other studies have disputed this. If true, this may make donors with darker hair more likely to test positive than donors with lighter hair.
The second controversy about ambient contamination producing false positives is of special concern to those donors, especially law enforcement and pharmaceutical workers, who may be handling drug contaminated items. To address and hopefully eliminate this concern, washing techniques have been developed and refined during the past decade.
For cocaine, hair-testing laboratories are also addressing the ambient contamination controversy by testing for cocaine metabolizes and establishing reporting criteria that require the presence of the metabolite to equal a certain percentage, usually 5%, of the total parent cocaine concentration. The assumption here is that for metabolism to take place the drug must have been ingested rather than adsorbed onto the hair. The most common metabolite used is benzoylecgonine, but also frequently reported are norcocaine and cocaethylene. There is also some thought that norcocaine might be a more accurate metabolite to use in this instance.
Oral fluid is the combination of fluids found in the mouth from the serous and mucous secretions of the glands of the oral cavity as well as the upper bronchial tree. It is not simply saliva.
Oral fluid is collected in many ways, but the most favored is an oral swab that is directly inserted into a preservative-containing tube and sealed for shipping. One advantage of this type of collection is that all collections are observed; hence it is thought there is minimal opportunity for the donor to attempt adulteration of the specimen. This is also true, of course, for hair collection.
Oral fluid cutoffs recommended by the Oral Fluid Advisory Board are listed below. Guidelines for laboratory based oral fluid drug testing, March 20, 2007.
- Marijuana 2 ng/mL
- Cocaine 8 ng/mL
- Opiates 40 ng/mL (6 AM 4 ng/mL)
- Amphetamines 50 ng/mL (Including MDMA, MDA, and MDEA)
- Phencyclidine 2 ng/mL
The window of detection for oral fluid drugs is 1 to 24 h. Ingested drug is metabolized, filtered into the glands, and secreted in the glandular fluid. This secretion mixes with residual drug that is adsorbed on the buccal membranes after smoking or chewing. The filtration and secretion process is heavily pH-dependent, and unfortunately this results in testing issues for the only acidic drug m the HHS 5 panel that is also the one confined most frequently in these testing programs marijuana. The acidic active metabolite of marijuana, THCA, is very minimally filtered and secreted, so only parent THC that is residual in the oral cavity is effectively found in the testing of oral fluid that is most commonly done today. There are early studies available that show that THCA may be found in pg/mL quantities in oral fluid, but at this writing this is not commonly confirmed and reported.
At this writing there are no effective validity tests for oral fluid specimens, but since the collection is an observed one it is thought that adulteration currently is a minimal problem. AS oral fluid testing becomes more widespread, we would expect that to change as it has with urine, but hopefully the evolution of oral fluid adulteration products; will be slow and difficult
Point-of Collection Testing
Point-of-collection testing (POCT) kits for drugs of abuse testing are available for both urine and oral fluid, and are aggressively marketed today. These are usually some proprietary version of immunoassay technology that can be read almost immediately after collection. Accuracy varies widely, and if Kilos are asked to be involved in the review of the POCT nonnegative results, it is wise to insist that the specimen to be reviewed be shipped under chain of custody to a certified laboratory for confirmation. Certified laboratories will usually re-screen these specimens before confirmation, and confirmation rates will vary.
The main benefit of POCT is an almost immediate negative report for the employer. Employers vary widely in the way they handle POCT non negatives, and some make a decision based solely on the screening result. Clearly, this should be discouraged because technology varies so widely in accuracy. Not only does the employer risk the loss of a potential employee because of a false-positive screen that does not confirm, there is also the risk of hiring somebody based on a false-negative screen.
POCT usage is expanding in workplace testing programs, particularly in the retails hospitality, construction, and temporary staffing sectors, as well as widespread application in the criminal Justice market for probation and parole testing programs & workplace testing they are most commonly used for pre employment testing as part of applicant screening and qualification processes. They are not authorized for use in DHHS or DOT mandated testing programs, and only the NRC allows their limited use in its Fit for Duty programs. State laws or regulations may restrict or prohibit POCT devices, and if permitted, frequently require laboratory confirmation of POCT presumptive-positive results.