New Iowa Laws Cause
Worries About False Positives on "Drug" Tests
See
The Des Moines Register's
Analysis of Iowa's New "Drug" Testing Law
Drug testing in Iowa
From the Des Moines Register
letters@news.dmreg.com
http://www.dmregister.com/
April 16, 1998
By Lynn Hicks -Register Business Writer
DRUG TESTS BRING WORRIES OF ACCURACY
"I go to extraordinary lengths before I call a positive."Dr. David
Berg, Medical review officer
The water-cooler talk is true: Poppy seeds can produce a positive test for heroin, and
cold medicine can suggest methamphetamine.
But medical experts say workers have little to worry about as changes in Iowas
drug-testing law go into effect today.
Thats because the new law requires medical review officers to evaluate drug
tests. They act as judges, determining whether the positive test is a result of illegal
drug use or a legitimate medical cause.
See
Hemp Foods Really
Do Cause Positive Drug Tests; Interview with Don Wirtshafter
"Im there to protect people from false positives as much as Im there to
find drug (evidence) for their employers," said Dr. David Berg, an MRO and director
of occupational medicine for the Des Moines office of HealthSouth. "I go to
extraordinary lengths before I call a positive."
Accuracy is a concern as private-sector employers gain more power to test employees for
drugs and alcohol. Occupational health clinics and laboratories say the law could lead to
more business, but they dont expect a rush starting today.
Business groups have been pushing for a change for years, and some construction
companies and other safety-sensitive employers are moving quickly to start testing, said
James Aipperspach, president of the Iowa Association of Business and Industry. But most
are still learning about the changes and deciding what options to take.
Employers are not required to test. They could randomly test workers for alcohol and
other drugs. They could test if they have reasonable suspicion that a worker is under the
influence. They could require workers to get treatment after a confirmed positive drug
test, or they could fire them. Critics say the law gives employers more power than police.
They also question the reliability of testing, and say the workers would have little
recourse if they falsely test positive.
The new law protects employers from liability unless they clearly should have known a
false positive test result was in error and ignored the correct test result.
The Iowa Civil Liberties Union isnt saying whether it will fight the law. But
lawyers and legislators have talked to the group about a challenge, said executive
director Ben Stone.
Random testing could result in more false positives, said Craig Zwerling, a University
of Iowa professor and expert on drug-testing.
Statistics vary widely on the likelihood of false positives,
depending on the test and the lab. Civil libertarians say 5 percent is a conservative
estimate.
Medical experts acknowledge that false positives arent impossible. But they say
urinalysis, the most common means of drug testing, has improved.
(Ed. note: They have been used for more than a decade. This is an
admission that there used to be even more false positives.)
The Iowa Methodist Medical Center laboratorys testing is more than 99 percent
reliable, said Rich Snyder, who supervises drug testing.
(Ed. note: Presumably, this is the best, but if there are
four million "drug" tests annually, this means that there would be forty
thousand false positives.)
The lab uses a combination of gas chromatography and mass spectrometry, which is
considered by most experts to be the most precise procedure for the detection of banned
substances. The new Iowa law requires such a technique to be used to confirm positive
tests.
(Ed. note: Second tests are an admirable precaution, but this has
the effect of aggravating the anti-marijuana character of the tests. Lay off cocaine for a
couple of days and you will be clean, but you will still test positive for marijuana if
you have used it a week before. This is why it is being recognized that "drug"
testing can encourage hard drug use.)
See
Random Drug Testing At Work Drives Employees To Swap Cannabis For Hard
Drugs -- UK Report
Employees can request a second confirmatory test at another lab, at their expense. If
that test comes back negative, the employer must reimburse the employee.
But tests still read some innocuous substances as illegal drugs. Because of the poppy
seed problem, the federal government is raising the threshold for the detection of opiates
in urine. Additional tests can be done to determine whether a Vicks inhaler is causing a
methamphetamine positive, experts say.
Medical review officers also look at more than the test, searching for evidence of
needle tracks or asking whether the person is on a prescription drug.
Testers also watch for adulterated samples. An industry is booming on the Internet,
providing drug users with tips and products to taint their tests. Snyder said most of the
methods, such as mixing the urine with bleach or soap, are easy to catch.
Medical review officers also are on guard for every excuse
imaginable. Theyve heard them all, including the one gold-medal snowboarder Ross
Rebagliati gave when he tested positive during the Olympics. Second-hand marijuana smoke
will produce a positive test only in extreme cases, research has shown.
"Theres no way," Berg scoffed.
Reporter Lynn Hicks can be reached at hicksl@news.dmreg.com
or (515) 284-8211.