What does blood test contaminated mean?

January 14, 2010

When a verdict of contaminated is passed upon any kind of diagnostic test it, usually means that the test has something from the external environment in it; simply put, the sample was tampered with. This is something that should not happen and would compromise the integrity and accuracy of the test conducted. Sample tampering is quite common when it comes to the tests for banned or dubious substances in the blood. Tampering is something that is usually not conducted for more serious medical tests that diagnose disease; however, even these are prone to contamination if not stored properly. One example is a test for bilirubin in the blood. If the sample is not stored away from light, the bilirubin count will be much less than in should actually be.

Drug testing is usually where this practice is the most common. Most employers will ask for some kind of medical test to be conducted on prospective employees to check for the presence of disease or banned narcotics. These include the testing for tetrahydrocanabinol from cannabis, methamphetamine from Speed, and any other drug that is considered banned. Benzodiazepines can also be tested from a blood sample though these are legal drugs that tend to be misused by addicts. Contamination usually occurs in urine samples more than in blood samples because contaminated blood samples can only be created by using someone else’s blood instead. This is what makes serum testing more accurate than urine testing. One of the greatest flaws of urine testing is that the urine can be rendered so dilute that nothing in it can be tested. Serum testing cannot have this problem because the constant blood pressure and the body itself will ensure that only a fixed volume of blood exists in the system. Drinking excessive amounts of water will therefore just cause a temporary and minute change in the constitution of the blood.

One of the most famous methods of cheating on urine tests is to drink an excessive amount of water to ensure that no useful quantities of banned substances can be measured. This is a trick that most samplers can figure out from the color of the urine itself. Devious minds have found a way behind this as well by simply having a tablet of vitamin B. This tends to make the urine color its usual yellow and may sometimes require a trained eye to notice the difference.

Submitted by M T on January 14, 2010 at 08:23

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