Pubdate: Mon, 21 Apr 2003
Source: Augusta Chronicle, The (GA)
Copyright: 2003 The Augusta Chronicle
Contact:  http://www.augustachronicle.com/
Details: http://www.mapinc.org/media/31
Note: Does not publishing letters from outside of the immediate Georgia and 
South Carolina circulation area
Author: Albert Ross Jr.

DRUG SCREENING LABS STAY BUSY

A common allergy pill could get a person busted on a drug test.

Medications such as ephedrine can come across as an amphetamine on a drug 
screening, said Dr. Jimmy Lea, a toxicologist at Medical College of Georgia 
Hospital.

"You run into trouble with that, in that there are a lot of 
over-the-counter drugs that cross-react and cause false positives," he 
said. "Especially this time of year, when you've got people taking allergy 
medicines."

Once a rarity, drug tests are now common for many in this country. 
President Reagan introduced drug testing for federal employees in 1986 when 
he signed the Drug-Free Workplace Order, according to Kent Holtorf's book 
Ur-ine Trouble. Private-sector employment testings were launched two years 
later with the passing of the Drug-Free Workplace Act. Today, labs conduct 
drug tests for several reasons, including employment screenings, probation 
periods, workers' compensation or accidents. Phil Williams of Mullins 
Laboratory said the lab did drug screenings in the late '80s for parents 
who wanted to know whether their children were using drugs.

Labs must be extra careful to ensure that a legal substance does not 
produce a positive test.

In order to guarantee that a pill or poppy seed bagel doesn't yield a 
positive result, some labs administer alternate tests to confirm whether a 
specific drug is being used.

They also perform tests to determine whether a specimen has been tampered 
with or mixed with a chemical to mask a drug.

Generally, urine is used as a test specimen because it gives a greater 
window of detection for drugs than blood or other bodily fluids. The 
process also collects a sample without the use of needles.

"Most of these drugs have a very short half-life," Mr. Lea said. "Think of 
the kidney as a sink. Everything you take in is going to be processed 
through that sink. It comes out as urine."

Immunologic screens use antibodies to detect drugs such as cocaine, 
marijuana, barbiturates, opiates, amphetamines and PCP, Mr. Williams said.

If a test comes back positive, it can be confirmed with thin-layer 
chromatography or gas chromatography-mass spectroscopy, processes similar 
to developing a picture.

Labs also have tests that can detect attempts to mask a drug. For example, 
if for some reason the immunologic screen and the chromatography differ, a 
dipstick method can be used to determine whether the sample has been 
altered. Mullins Lab uses a device called AdultaCheck 4.

The AdultaCheck tests for creatinine, glutaraldehyde and nitrites and 
checks the pH levels. If the creatinine level is low, someone has diluted 
the urine.

The pH level might change slightly, but if it goes above a certain level, 
it is not normal. There should be no sign of glutaraldehyde or nitrites 
because the body doesn't produce them.

Their presence can suggest that someone used an additive to mask a drug. 
Although people use such adulterants to mask their test, Mr. Williams said 
there is nothing anyone can consume to cover drugs in urine.

"Anybody that I know that does drug screens checks for specific gravity and 
creatinine concentration," he said. "If they're low, then that basically 
tells you that the specimen wasn't adequate to assess the individual's status."
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MAP posted-by: Beth