Hair testing, instant drug testing gaining popularity
Question: We took notice when hair testing and instant, on-site drug testing became available a few years ago, but we didn’t adopt the methods right away because they didn’t seem proven yet. But what about now? Are those methods becoming accepted for workplace drug testing?
Answer: Both methods of drug and alcohol testing have caught on rapidly, becoming standard parts of occupational health, says Ben Hoffman, MD, MPH, medical director with Business Health Management in Hampton, NH, and Boston. Hoffman has studied occupational drug testing extensively and is one of the few medical review officers (MROs) in the country who oversee hair testing programs. He tells Occupational Health Management that hair testing proponents have encountered some stumbling blocks, but health professionals have eagerly adopted the technique.
One of the big controversies has involved the possibility that hair testing results can be influenced by hair color and race. Critics have contended that darker hair is more likely to test positive, and since some races are more likely to have dark hair, the testing can be unfair on a racial basis. Hoffman has studied the debate and says the criticism is unjustified. He is publishing a study soon in which he conducted the first hair testing research addressing possible bias in a workplace setting.
"There was no bias," Hoffman says. "Hair color bias should not be a deterrent to using hair testing. There have been some studies showing that some hair colors will take up a cocaine solution more than others in the lab, but our study shows that there is no such effect in a real-world setting."
The bias might occur at low thresholds, since there may be some physical difference in how different hair types retain drug products, Hoffman says. But at the levels employers use to detect drug use, the issue is moot, he says.
The same sort of debate applies to the issue of bystander exposure being detectable in a hair sample. Critics have argued that hair testing can produce a positive result when the subject has not consumed drugs but was in the vicinity and the hair absorbed marijuana smoke, for instance. Hoffman says research also has proven that the relatively high cutoff points for positivity avoid any problems with bystander exposure. Also, the tests measure mostly metabolites of drugs that occur in the hair only when the subject has actually consumed drugs.
"Being in the same room, you could involuntarily inhale some and produce metabolites, but the levels would be much lower than what the cutoffs allow," he says. "You need a high level of consumption to test positive."
There is one issue concerning hair testing that Hoffman says is a legitimate concern. Variations from lab to lab can threaten the reliability of the results, so Hoffman advises paying particular attention to finding a qualified lab. Ultimately, Hoffman says the country needs federal regulation of hair testing labs.
Occupational health professionals and employers have eagerly embraced the hair testing technique since it first appeared on the scene and OHM first reported on it. (For the earlier report, see OHM, June 1996, p. 64.)
"I find that it’s very popular," he says. "Many very big companies are using it, and I see it all over the place these days. The type of client that instantly finds hair analysis appealing is one that knows there is a drug problem on the job. They have knowledge of drugs at work, but the urine testing didn’t pick it up so hair testing provides a way to more successfully detect drug users."
A main supplier of hair tests, Psychemedics in Cambridge, MA, reports that it has completed more than 2 million corporate drug tests. The company reports that its hair tests have been used by more than 1,600 corporations, including many Fortune 500 companies.
On-site or instant drug testing also has become a routine part of many occupational health programs, Hoffman says. Employers and providers find on-site testing to be especially useful when the worker is at a remote site such as an oil rig, and for post-accident or for-cause testing. Another use is for a situation in which the employer needs very quick turnaround for economic reasons.
"Think of two big employers next to each other vying for the same hourly retail employees," he says. "They can’t wait long to make a job offer. A typical drug test could cause them to lose good people because the person goes next door and takes a job. You can save yourself a day or more by using on-site testing."
There are several manufacturers promoting on-site test kits, with most suggesting their use for pre-employment testing for alcohol and a wide range of illegal drugs. The test usually is performed with a test card or stick dipped in a urine sample, or sometimes the sample cup itself contains the testing medium. The instant tests can be inexpensive, but even if you charge more than for other testing options, many employers are willing to pay for results that come in less than five minutes. The tests originally were developed for use in the criminal justice system in 1990, but then employers and occupational health providers slowly took interest over the next few years.
Hoffman offers one caveat about on-site testing: The tests may produce unusually high rates of false negatives. A positive result would be confirmed by other testing before the applicant is turned down, but a false negative will just allow the applicant to go right to work. That could be an important point to consider if the job is safety sensitive, he says.
"On-site tests can be useful in some situations, but I think the false negative rate is a concern," he says. "Unless there is an overwhelming reason to use them, I discourage employers from using them."
[For more information, contact:
Ben Hoffman, Medical Director, Business Health Management, 4 Liberty Lane, Hampton, NH 03842. Telephone: (603) 929-1640.
Psychemedics Corp., Cambridge, MA. Telephone: (617) 868-7455. ]
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