| GENERAL INFORMATION
ON DRUGS OF ABUSE AND DRUG DETECTION TESTING: For information on drugs, you can click on
one of the
following links, or view brief summaries of common
drugs of abuse and drug testing.
Drugs and Human Performance Facts Sheets
Medline Plus
A Service of the U.S. National Library of
Medicine and National Institute of Health
NIDA
The National Institute on Drugs Abuse
The detection times in urine are significantly greater than detection times in
blood, which is also generally much more expensive. The presence of a drug or drugs in
urine does not provide information as to whether the individual is actually under the
influence at any particular time. Likewise, no determination can be made from urine as to
the amount of the dose or the time of the dose.
Blood testing, on the other hand may
provide more suitable information about whether or not an individual is "under the
influence", though this may not be conclusive in all cases.
Urine drug testing accuracy is variable
depending on how the testing is done. Drug
testing is extremely accurate and reliable when all aspects of the testing process are
done properly. On the other hand, the information obtained may be very misleading and
inaccurate when poor procedures or testing methods are utilized. Drug testing will only be
reliable when the consumer knows how it should be done and then demands from the industry
that it is done properly.
Unfortunately, today, the majority of drug testing is poorly done and plagued with
unreliable information. Below are aspects that should provide enough information to
empower the consumer to demand proper testing procedures. There are three aspects to
reliable drug testing:
- Strict collection procedures;
- Proper Testing Procedures;
- Random notification.
Specimen Collection: Collection of Urine should be done following a process of
positive identification of the individual and full chain of custody procedures. In
addition, and more importantly, the specimen should be certified by a means of temperature
measurement with a digital thermometer. Acceptable ranges of temperature measurement
should be within 96 to 99 degrees to preclude samples that are adulterated and or
substituted.
Witnessed collections are not necessary and in fact are not as reliable as the digital
measurement of temperature within 96 to 99 degrees. (If witnessed collection is done, it
should also have the digital measurement done).
Plastic "temperature strips" which are attached to the vial should not be
used to measure the temperature. Current widespread practice is for collection facilities
to allow temperature certification within a range of 90 to 100 degrees Fahrenheit. In
addition, it is also common to use "temp strips" for the determination of the
temperature. These practices do not preclude adulteration and/or substitution of the
specimen and are probably the source of most of the inaccuracy and unreliability of urine
drug testing today.
SAMSHA (Substance Abuse and Mental Health Services Administration) has unwittingly
encouraged these faulty practices by stating these wide limits (90 to 100 degrees) of
temperature acceptability within the regulations. This has fostered nationwide
incompetence in this area, allowing "positive" subjects to substitute or
adulterate their urine unchecked and resulting in indeterminable number of "false
negative" results.
DDL's procedure for collection of specimens is available to any collection facility
that desires to improve their collection procedures (see SPECIMEN
COLLECTION).
Testing Procedure:
Ensure all positive results are confirmed by
GC/MS or LC/MS analysis. This is critical to ensure no "false
positive" results occur.
There are two approaches to testing;
cut-off type tests and limit of detection tests. A
cut-off type test has an administrative "limit" set to report a
positive result. If the drug is identified, but is below the
limit, it is reported as "not detected".
The LIMIT OF DETECTION - The limit of
detection tests reports any detectable amount present within the
capabilities of the laboratory. This is typically well below
the administrative "cut-offs" discussed above. The most reliable "negative" test
results are those which are determined by a ZERO TOLERANCE testing procedure. SAMSHA
certified laboratories are required to adhere to established cutoff concentrations. In
other words, a specified amount of the drug or drugs is allowed to be present and still be
reported as "negative". This results again in an increased number of "false
negatives", or the reporting of a test result as "negative" when the drug
is actually present.
To provide the most accurate and reliable information in a "negative" test, a
ZERO TOLERANCE test should be done. Require that the laboratory follow zero tolerance by
requesting that the detection limit of the drug or drugs be ruled by the LIMIT OF
DETECTION of the GC/MS procedure. If the laboratory cannot accommodate that request, find
another certified laboratory that will. (SAMSHA laboratories will not perform zero
tolerance testing since the regulations require that established cutoff limits be
followed).
Zero tolerance
testing may also be more expensive, but will provide the most reliable information if
testing is "negative" (assuming of course that the specimen was collected
properly).
Random Call: Random notification is an important aspect of the reliability of
drug detection. The detection of any drug is subject to the timing and amount of the dose.
Subjects who have used illicit drugs may allow their system to clear if they have enough
time. The notification of the individual should be done so as not to allow enough time to
enable the person to clear the drug. Usually a limit of 24 hours is acceptable to detected
most drugs besides alcohol (ethanol). If ethanol is of concern the collection should be
done within 3 to 4 hours.
For information on drugs, you can click on
the following link to the
National
Highway Traffic Safety Administration "Drugs and Human Performance Fact
Sheets"
or view brief summaries of common drugs below.
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