The Tests

EMIT (Enzyme multiplied immunoassay technique) This is the most widely used test by employers because of its low cost. More than 95% of employers use this as an initial test. Manufactured by the Syva company, its accuracy is so suspect that the company itself recommends a more refined GC/MS test to confirm positive results. Because many employers don't want to spend the $100 to $150 dollars charged for the GC/MS, employees have been fired on the results of the EMIT test alone. Courts have ruled that repetition of the EMIT test does not constitute confirmation of a positive drug finding.
This test does not measure drugs in the urine directly. Rather, a reagent is added to the urine sample to bind with the metabolite of the drug being searched for. Then a second reagent is added to decrease the enzyme activity of the first. The result is read by a light sensing instrument which measures the photometric spectrum. The problem is reagents combine with substances similar to drug metabolites. Hence Advil, Sinex or other medicines may be similar enough to certain illegal drugs to cause a positive reaction.

RIA This test is somewhat more sophisticated and more expensive than the EMIT test. Produced by Roche Diagnostics, Inc. under the name Abuscreen, this test is occasionally used by the armed forces. This more complicated procedure involves adding a radioactive antigen to the sample of urine and analyzing it by a machine. Mistakes come from poor calibration. The manufacturer states "a positive test result should be confirmed by a...GC/MS ".

TLC This stands for thin layer chromatography. The procedure involves adding solvent to urine to extract drugs and then comparing color spots on a TLC plate to that of a standard. TLC relies on the subjective judgment of a technician and requires considerable skill and training. False positives result from mis-interpretations. It is not widely used.

GC/MS Gas Chromatography/Mass Spectrometry. In this, the most sophisticated test, a sample of urine is injected into the machine. The urine separates as it travels from the injection port to the detector and as the sample emerges from the gas chromatograph, it is ionized by electron bombardment. The resulting positive ion mass fragments are read by the mass spectrometer. The results are produced on a computer print out.
While in theory the GC/MS test is excellent, in practice, errors creep in. Temperature, pressure, and storage time of samples must be rigidly controlled. Expensive environmental controls and immaculate cleaning practices must be observed. Too often, commercial labs have an economic incentive to rush testing, cleaning and maintenance. Mistakes most commonly happen when the highly sensitive machine is not thoroughly cleaned. Your sample could easily be contaminated by small traces from the previous urine sample.
Bobby Gladd a respected laboratory quality assurance analyst reports documentation of false reports of GC/MS tests in the environmental field. Researcher Gladd believes that many results could be challenged in court for faulty procedure. For those considering a legal challenge to false reports Gladd's firm might be for hire. His number appears under "useful Numbers".

Hair and Saliva Tests have received considerable publicity. In theory a snippet of hair near the nape of your neck could indicate illegal drug usage for the last several months. The accuracy of these tests has not been determined. The cost of hair tests and saliva tests have been prohibitive. Because employers are sticking with the inexpensive EMIT test, these tests have not been adopted and are not a matter of concern at the present.

Automated Tests Both the EM/2 and the FIT tests represent the next generation if tests which measure the rapid eye movement of the pupil. The makers claim a "97%" accuracy rate. This means 3,000 out of every hundred thousand workers would be falsely fired from their job. Problems with eye or nerve abnormalities raise questions about test accuracy. Makers claim they could video each test to guarantee its validity which raises difficult "chain of custody" issues.

The SEDI test relies on 200 computer generated questions concerning rapidly changing numbers. The employee must spot numbers outside a given range. This is an impairment test. Fatigue, emotional distractions, and even caffeine might create failures. Currently none of these factors are illegal in the work place. The ONLINE assay utilizing a micropartical technology claims a better than 98% accuracy rate. While these tests are pushed by various manufacturers, high cost remains a prohibitive factor. As we all know automated systems, like check outs in the super market, are constantly plaguedby errors. This automated technology suggests giving the employer constant, daily, twice a day, or more surveillance over employees.

Overall testing problems As drug testing has become a growth industry many "labs" which are nothing more than marketing firms have sprung up. While Federal jobs require the use of NIDA certified labs, private employers can choose whomever offers the best price.
In practice , control of samples is often careless. There are numerous cases of samples being mislabeled or mixed up. Increasingly, employers are not showing workers their actual lab reports. Without a lab report you might never know if a careful chain of custody was recorded. You could be the victim of another person's urine sample, as was heavyweight champion, Bone Crusher Smith. Smith's reputation was blackened by a positive drug test after his title fight with Mike Tyson. Almost a week later, an investigation reported that Smith's sample had been mixed up with that of another fighter. The mistake received little press play. If this happened to a celebrated heavyweight title fighter, what mistakes are made with the average working person.
Many employees of local labs are ill-paid and poorly trained. Sanitation and maintenance standards are left up to the lab. Restaurant kitchens are more closely inspected than these laboratories which issue test results that cost people their jobs, their standing in the community, and their self respect.


Void Where Prohibited