Is Hair Testing for Drugs the ‘Gold Standard’?

By Roy Maurer Jun 17, 2015
Louisiana’s drug-testing law was amended to authorize laboratories to process the results of hair testing for drugs. Gov. Bobby Jindal signed House Bill 379 into law June 5, 2015, permitting the state’s employers to test hair specimens through laboratories certified by the College of American Pathologists. State Rep. Paul Hollis, R-Covington, sponsor of the legislation, called using hair samples “the gold standard” of drug testing.

Hair testing is the only drug-testing method available that provides up to a 90-day drug-use history, according to Dr. Barry Sample, director of science and technology at Quest Diagnostics Employer Solutions, a drug-testing service provider. When compared with urine testing, hair testing tends to provide a greater number of positives due to its longer detection window.

“Our hair testing detects nearly twice the number of positives as our urine test,” Sample said. “Unlike urine drug testing, which may only detect drug use within the past 2-3 days, hair testing is able to detect a pattern of repetitive drug use for up to 90 days.”

Another reason why some employers prefer testing hair rather than urine is because of the popularity of devices and chemicals available on the Internet to assist people in “beating” or urine tests, said Kathryn Russo, a shareholder in the Long Island, N.Y., office of Jackson Lewis and one of the practice leaders of the firm’s Drug Testing and Substance Abuse Management Practice Group.

Experts agreed that urine testing is well-suited to detect recent drug use, but a hair test is the most effective way to evaluate long-term patterns of use. “This makes it an excellent option for a pre-employment or random testing program,” Sample said.

Hair testing should never be used for “reasonable suspicion” testing or post-accident testing, Russo said, because that kind of testing “typically takes place immediately after the accident or reasonable suspicion determination,” and “hair grows very slowly, so it cannot be used to determine whether a person has used drugs today.”

Prohibitions and Issues When Hair Testing

Some of the tricky issues around hair testing for drug use include potential violations under the Americans with Disabilities Act (ADA), and federal and state anti-discrimination laws, as well as retesting concerns.

“If an individual used drugs 90 days ago and then completed drug rehabilitation, he or she conceivably could still test positive on a hair test, even though he or she is no longer a current user of illegal drugs,” Russo explained. “If the company takes adverse action based on the positive hair test, the applicant or employee could claim that he or she is erroneously regarded as a substance abuser when he or she is not, in violation of the ADA and comparable state laws.”

In addition, Russo noted that employers considering hair testing need to be careful with employees of certain religions, such as Sikhism or Rastafarianism, which prohibit members from cutting their hair. “Applicants and employees who are members of these religions should not be subjected to hair testing,” she said.

Retesting brings up another issue for employers considering using hair samples for drug tests. Maine, Maryland, Minnesota, North Carolina, Rhode Island, Vermont and Boulder, Colo., require that applicants and employees who test positive must be offered the opportunity to have a confirmatory retest on the original specimen, Russo said. “Retesting the original specimen may be technically difficult or impossible. We have been advised by individuals in the drug-testing industry that hair testing does not permit later testing of the original specimen, but employers should check with their own drug-testing vendors to get their technical expertise on this issue,” she said.

Hair testing for drug use is permissible in all states and localities except Hawaii, Iowa, Montana, Nebraska, Oregon and San Francisco, Calif. “In Connecticut, it is unclear whether hair testing is permissible because the drug-testing law refers only to urine testing,” Russo said.

Roy Maurer is an online editor/manager for SHRM.

Follow him @SHRMRoy

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