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What Employers Hear From The Drug Test
Manufacturers
The following information is published to provide
the reader a perspective of the information commonly available to companies and
individuals considering implementing a Drug Testing program within their
organizations.
Background
Drug-Free Workplace programs, and
particularly their drug testing provisions, have been the subject of numerous
lawsuits over the past decade. In the public sector, these have involved
questions of the right to privacy, the Constitutional freedom from unreasonable
searches by the government when an agency acts as an employer, and due process.
All employers, even those with well-intentioned programs, can face court
challenges to their Drug-Free Workplace policy based on questions of negligence
(negligent hiring, supervision, libel, and slander), contract law, and
discrimination (racial, sexual, and disability).
Consulting with an attorney
experienced with labor and employment matters in your State is always the best
course of action to take before implementing a Drug-Free Workplace program.
There are, however, some general "rules of the road" that can help you avoid
mistakes and lessons learned the hard way by others.
The following suggestions about
minimizing legal risks and exposures are summarized from The Drug Enforcement
Administration's Guidelines for a Drug-Free Workplace.
Do:
Become familiar with common symptoms of drug use.
Assume that no one in your organization is immune to the problem of drug and
alcohol abuse.
Know your employees. Become familiar with each one's skills, abilities, and
normal performance.
Document job performance regularly, objectively, and consistently for all
employees.
Keep written records that objectively document the performance of troubled
employees. These can be used as a basis for referral for to the employee
assistance program and/or for testing.
Take action whenever job performance fails, regardless of whether drug or
alcohol use is suspected.
Know the exact steps to be taken when an employee has a problem and is ready to
seek help.
Obtain appropriate advice when a problem is identified or suspected, and have a
witness to any actions when confronting an employee.
Don't:
Misuse the Drug-Free Workplace program to discipline employees for unrelated
problems.
Single out any employee or group of employees for scrutiny under the policy. Be
consistent in your actions with all employee groups or classes.
Confront a suspected drug dealer [or user] alone. Always have a witness.
Implement a verbal policy. An effective policy must be written, circulated, and
acknowledged in writing by employees in order to have strong legal standing.
Treat employees who test positive differently. All employees who test positive
must be treated consistently to maintain the integrity of the program.
Take action against employees based on the results of a drug screen only. Always
obtain the results of a gas chromatography/mass spectrometry (GC/MS)
confirmation test before taking action.
Offer rehabilitation selectively.
Address drug abuse without including alcohol abuse in the policy.
Implement a policy and program unilaterally if the workforce is represented by a
union. The National Labor Relations Act requires that terms and conditions be
included in your bargaining agreement and a drug program falls into that
requirement.
QUESTION AND ANSWERS
1 - Why do companies use urine screening?
2 - How many companies are using pre-employment screening?
3 - If in- service testing is used, how often should
employees be screened?
4 - What about individual rights, privacy, and
confidentiality?
5 - Who should set up a drug screening program?
6 - How does one develop a policy?
7 - What level of drug in the urine indicates and individual
is impaired?
8 - How reliable are urinalysis methods?
9 - What does laboratory quality assurance mean?
10 - Many reports have appeared in the news media about legal
cases in which experts have questioned the validity of a urine assay result.
11 - Does this indicate that the assay methods are not
sufficiently reliable for broad application?
12 - What are the primary methods being used for initial
testing (screening) of urine specimens?
13 - What are "confirmation assays"?
14 - What is the preferred method for confirmation of
presumptive positives from initial urine screens?
15- What do assay "sensitivity" and assay "cutoff" mean?
16 - How can false positive results occur?
17 - How frequently do false positives occur?
18 - What substances have caused false positives with drug
screening assays?
19 - Do poppy seeds cause false positives for opiates?
20 - How can false positives be eliminated?
21 - How can safeguards be provided to ensure an employee
will not be accused wrongfully?
22 - Are rigorous and costly laboratory procedures always
necessary?
23 - Can passive inhalation of marijuana smoke lead to a
positive urine even if the person did not smoke a joint?
24 - Can time of previous drug use be determined from
analysis of urine?
25 - What adverse health effects can be correlated with the
presence of marijuana metabolites in urine?
26 - Can the level of "intoxication" of an individual
due to marijuana use be gauged by urinalysis?
27 - Can his or her "use patterns" be determined?
28 - How long after use can cocaine/ heroin/ phencyclidine/
marijuana be detected by urinalysis?
29 - If a urine sample is negative a day after a positive
sample, does this mean the first result was wrong?
30 - How are the results of a urine drug assay expressed?
What Employers Hear From The Drug Test Manufacturers
1 - Why do companies use urine screening?
Answer: The evaluation of employees to determine fitness
for duty has long been performed in industry. Within the context of
occupational medicine programs, physical examinations were initially performed
to ensure the selection of personnel free of medical conditions which would be
likely to interfere with their ability to work safely and efficiently. In
recent years, within the context of health promotion and wellness programs, an
additional purpose of the medical evaluation has evolved; that is, to address
risk factors that may impair employee health (e.g., poor nutrition, substance
abuse, hypertension). As the incidence and prevalence of drug abuse in the
United States have risen, many companies have developed pre-employment and
in-service drug screening programs. The primary purpose of these programs
is to protect the health and safety of all employees throughout the early
identification and referral for treatment of employees with drug - and alcohol -
abuse problems. The integration of drug screening with programs of
treatment, prevention, and drug education is proving to be an effective way of
managing substance abuse problems in industry.
2 - How many companies are using pre-employment screening?
Answer: Urinalysis for drug use is being used to screen
job applicants by many of the Nation's largest employers, including major
corporations, manufacturers, public utilities, and transportation, and many
small businesses. In general, most companies have an established policy
that they will not hire individuals who present positive urines indicating
current use of illicit substances. However, many of these companies also
counsel applicants who fail the drug screen to seek treatment and to reapply.
Several surveys have collected information on drug
testing in industry. These surveys have varied in size, target
populations, and focus, but together give a picture of the status of testing in
business and industry. Overall, 6 surveys have found that from 20-33% of
companies surveyed have a drug testing program, with significant differences
between companies of different types.
In general, the larger the company, the more likely
it is to have a drug testing program. One survey by the American
Management Association found that 15% of companies doing under $15 million do
testing, while 36% of companies doing over $1 billion do some testing. Of
Fortune 500 companies, over 50% report testing. Other surveys have also
documented this relationship. In a college placement Council survey, while
overall 28% of companies did testing, 58% of those with over 5,000 employees
have testing programs. Larger companies are leading in the adoption of
drug testing programs.
There are also significant differences by industry.
Federally regulated industries are most likely to test -- utilities (91%) and
transportation (81%); followed by manufacturing (44%), communications (34.5%),
mining/construction (15.3%), and with the lowest rates in retail (13.0%),
services (12.6%) and finance and insurance (8.7%) industries.
3 - If in service testing is used, how often should
employees be screened?
Answer: Company policy regarding the frequency of drug
screening is usually determined with consideration of risk factors associated
with safety, security, and health. Over the last 5 years, a continuum of
drug screening policies has evolved, ranging from post accident evaluation to
random, unannounced testing. The least intrusive is an
incident-driven policy wherein screening occurs only after an accident or
"incident" (e.g., a fight) or other "probable cause" event. High-risk or
safety sensitive occupations where public safety is of special concern may
require routine scheduled screening. In these cases, screening is often
tied to evaluation of fitness for duty or to annual physical examinations.
In extremely hazardous and high-risk occupations, periodic unannounced or random
testing to assure the health and safety of employees may be warranted.
4 - What about individual rights, privacy, and
confidentiality?
Answer: How best to deal with the problems associated
with employee drug use is a complex issue. Principles of public safety,
efficient performance, and optimal productivity must be balanced against
individuals' reasonable expectations of privacy and confidentiality. Job
situations where there is a substantial risk to the public safety will surely
justify greater permissible intrusions than would be acceptable where risks to
the employee or community are perceived as minimal. On the one hand, an
employer has the right to demand a drug-free workplace; on the other, an
employee has reasonable rights to privacy and confidentiality. Since
substance abuse is a diagnosable and treatable illness, policies and procedures
should be written to ensure the confidentiality of employee medical records, as
in any other medical or health-related condition. Urinalysis test results,
which could be part of such a diagnosis, should be treated with the same
confidentiality.
5a - Who should set up a drug screening program?
5b - How does one develop a policy?
Answer: The first priority should be to establish whether
there is a need for a screening program. Is drug use present and
significant? Can a drug use deterrent be established by means other
than urine screening? The decision of whether or not to establish a
drug-testing program will also depend to a large extent on the work setting.
The initial question that management should consider is, "What is the purpose
for testing?" The key concerns must be for the health and safety of all
employees (i.e., early identification and referral for treatment) and to assure
that any drug detection or screening procedure would be carried out with
reasonable regard for the personal privacy and dignity of the worker.
The second critical question to consider is what you
will do when employees are identified as drug users. Once these issues are
clarified, experts should be consulted to assist in drafting a policy.
6 - What level of drug in the urine indicates and individual
is impaired?
Answer: Although urine screening technology is extremely
effective in determining previous drug use, the positive results of a urine
screen cannot be used to improve intoxication or impaired performance.
Inert drug metabolites may appear in urine for several days, even weeks
(depending upon the drug), without related impairment. However, positive
urine screen do provide evidence of prior drug use.
7 - How reliable are urinalysis methods?
Answer: A variety of methods are available to
laboratories for drug screening through urinalysis. Most of these are
suitable for determining the presence or absence of a drug in a urine sample.
Accuracy and reliability of the methods must be assessed in the context of the
total laboratory system. If the laboratory uses well-trained and certified
personnel who follow acceptable procedures, then the accuracy of the results
should be very high. Laboratories should maintain good quality control
procedures, follow manufacturer's protocols, and perform a confirmation assay on
all positives by a different chemical method from that used for the initial
screening. The Department of Health and Human Services (DHHS) has
published Mandatory Guidelines for Federal Workplace Drug Testing Programs
(Guidelines), as well as Standards for Laboratory Certification. All
Federal agencies are required to follow these Guidelines and may only purchase
services from laboratories that have been certified through the DHHS-sponsored
National Laboratory Certification Programs. Drug testing guidelines for
Federal agencies specify use of Immunoassays for initial screenings and gas
chromatography/mass spectrometry for the confirmation tests.
Equally important are the procedures that are
followed to document how and by whom the sample is handled from the time it is
taken from the individual, through the laboratory, until the final assay result
is tabulated. This record is referred to as the "chain of custody" for the
sample.
8 - What does laboratory quality assurance mean?
Answer: Quality assurance procedures (QA) are documented
programs which the laboratory follows to ensure the highest possible reliability
by controlling the way samples for analysis are handled and instruments are
checked to be sure they are functioning correctly, and by minimizing human
error. Standard and blank samples are analyzed along with the unknown
samples to ensure that the total laboratory system is producing the expected
results. These known samples are referred to as quality control samples.
Quality assurance is described in detail in NIDA's Standards for Certification
of Laboratories engaged in Urine Drug Testing, and in the NIDA Research
Monograph 73 entitled Urine Testing for Drugs of Abuse.
9a - Many reports have appeared in the news media about legal
cases in which experts have questioned the validity of a urine assay result.
9b - Does this indicate that the assay methods are not
sufficiently reliable for broad application?
Answer: There is little controversy among experts in
those cases where appropriate methods were used, good laboratory procedures
where followed in the context of a good quality assurance program, and
adequately trained personnel carried out the analysis and interpretation.
10 - What are the primary methods being used for initial
testing (screening) of urine specimens?
Answer: Most urine screening today is done by immunoassay
methods such as radioimmunoassay (RIA), enzyme immunoassay (EIA), and
fluorescence polarization immunoassay (FPIA).
11 - What are "confirmation assays"?
Answer: If an initial screening assay shows a sample as
being positive, a second assay should be employed to confirm the initial result.
Two different assays operating on different chemical principles having both
given a positive result greatly decreases the possibility that a methodological
problem or a "cross reacting" substance could have created the positive.
A confirmation assay usually should be carried out
by a method which is of comparable sensitivity and which is more specific (or
selective) than a screening assay. Examples of confirmation methods
currently in use include gas chromatography (GC), gas chromatography/mass
spectrometry (GC/MS), and high performance liquid chromatography (HPLC).
These are sophisticated instrumental methods requiring highly trained
technicians to operate them. Properly run, they are capable of providing
highly selective assays for a variety of drugs.
12 - What is the preferred method for confirmation of
presumptive positives from initial urine screens?
Answer: Gas chromatography coupled with mass spectrometry
(GC/MS) has evolved as the preferred method for confirmation of a positive urine
screening test, primarily because it provides the greatest level of specificity
and therefore the greatest margin of certainty and legal defensibility.
Additionally, it is the only method which provides a documented data record
suitable for review and interpretation by an outside expert. This method
of confirmation is required of laboratories which are certified for urine drug
testing for Federal employee programs.
13 - What do assay "sensitivity" and assay "cutoff" mean?
Answer: The ability of any assay to detect low levels of
drugs has an inherent limit. The concentration of drug in the urine sample
below which the assay can no longer be considered reliable is the "sensitivity"
limit. The "cutoff" point is the concentration limit that will
actually be used to assay samples. Any sample which assays below this
level is considered a negative. Manufacturers of commercial urine
screening systems set cutoff limits to their assays well above the sensitivity
limits of the assay to assure accuracy and reliability and to minimize the
possibility of a sample which is truly negative giving a (false) positive
result.
For example, standards for testing of Federal
employees require all initial immunoassay screens for detection of marijuana use
to be set at 100 ng/ml, although virtually all commercial immunoassays are
"sensitive: enough to be run at cutoffs far below this level. Setting the
cutoff at 100 ng/ml not only decreases the possibility of a false positive
resulting from operating the assay too close to its limit of sensitivity, but
also significantly decreases the possibility of a positive test resulting from
passive inhalation.
14 - How can false positive results occur?
Answer: It is theoretically possible for substances other
than the drug in question to give a positive result in a screening assay.
This is sometimes referred to as "cross reactivity." However, most
substances which could possibly cause such a cross reaction have been evaluated
by the assay manufacturers and found not to interfere. These companies can
supply brochures for all their drug screens which detail the extent to which
other drugs or substances cross react with the assay.
False positive results can occur due to human error.
This is directly dependent on the experience of the laboratory personnel
conducting the test and on the laboratory quality assurance procedures any good
laboratory imposes to recognize such errors.
15 - How frequently do false positives occur?
Answer: While there have been some reports of the
occurrence of false positives, these can usually be traced to poor quality
control procedures at the laboratory site or to the fact that appropriate
confirmation procedures were not used to verify the "presumptive positive."
Typically the samples which were the subject of these reports were specimens
which tested positive by an initial screen but could not be confirmed by the
confirmation assay. Such "unconfirmed positives" should always be reported
as negatives.
16 - What substances have caused false positives with drug
screening assays?
Answer: Ibuprofen, a nonsteroidal anti-inflammatory agent
used for pain relief found in Advil, Nuprin, and similar over-the-counter (OTC)
drugs was found to interfere with the Syva EMIT test and cause apparent false
positives for the marijuana metabolite. Syva has corrected the problem by
altering the formulation of the EMIT kit. These substances no longer cause
false positives in initial screening assays. This potential error was
never a problem for other immunoassays, nor for EMIT if a confirmation assay was
used.
Phenylpropanolamine (PPA) and ephedrine, found in
OTC diet pills and cold remedies, are similar in chemical structure to
amphetamines and can produce an apparent (false) positive for amphetamines in
immunoassay screens.
Neither ibuprofen, PPA, nor ephedrine preparations
will lead to a false positive error, however, if an appropriate GC/MS
confirmation assay is carried out, because the GC/MS technique can specifically
identify the illicit drug.
17 - Do poppy seeds cause false positives for opiates?
Answer: Poppy seeds commonly used on bagels or other
baked goods frequently do contain sufficient amounts of morphine to produce
detectable concentrations of morphine in urine, even though the amount of
ingested morphine is insufficient to cause any behavioral effect in the
individual. It has been reported in the literature that ingestion of three
poppy seed bagels can lead to urine morphine levels in excess of 2,500 ng/ml and
codeine levels greater than 200 ng/ml.
Therefore a positive urine resulting from poppy
seeds is not a false positive, since the drug is actually present in detectable
levels. Obviously, a caution must be exercised in interpreting such
a positive result as an indicator of heroin use.
One method to distinguish true heroin use is to
analyze the urine specimen for 6-monoaccttylmorphine, a heroin metabolite which
cannot come from poppy seeds. Recently testing programs have begun routine
screening for this metabolite in urines tested opiate positive by an immunoassay
screen. The assay requires use of GC/MS methods at very low concentrations
and is therefore a highly sophisticated procedure
18 - How can false
positives be eliminated?
Answer: Probably the two most important reasons for the
occurrence of false positives are poor quality assurance (QA) procedures in the
laboratory and the absence of an appropriate confirmation assay to confirm
presumptive positives arising from an initial screening procedure.
A good laboratory will impose a stringent and
well-documented QA system and will also use a well-validated confirmation assay
for all samples that test positive in a first screen.
19 - How can safeguards be provided to ensure an employee
will not be accused wrongfully?
Answer: One essential part of any drug-testing program is
the medical review of laboratory results. A positive drug test result does
not automatically identify an employee/applicant as a user of illegal drugs.
Confirmed positive test results for amphetamines, barbiturates, opiates, and
even cocaine can result from legitimate medical treatment.
The DHHS Guidelines for drug testing by Federal
agencies require that a licensed physician, with knowledge of substance-abuse
disorders, be contracted to review and interpret any positive test results.
The guidelines specify:
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In carrying out this responsibility, the Medical
Review Officer shall examine alternate medical explanations for any positive
test result.
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This
action could include conducting a medical interview with the individual, review
of the individual's medical history, or review of any other relevant biomedical
factors.
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The Medical Review Officer shall review all medical
records made available by the tested individual when a confirmed positive test
could have resulted from legally prescribed medication.
If procedures such as those prescribed for the
Federal drug testing program are followed, the chances of an individual being
wrongfully accused of using illicit substances will be virtually eliminated.
20 - Are rigorous and costly laboratory procedures always
necessary?
Answer: The need to use assay systems which are based on
state-of-the-art methods and rigorously controlled procedures should be
mandatory in situations where the consequences of a positive result to the
individual are great. In a case where the consequences are less severe, such as
a counseling situation, it might be acceptable to use less rigorous systems.
For instance, pediatricians sometimes use portable screening systems in their
practices to assist in the diagnosis and treatment of drug problems in
adolescents. Deterrence screening programs might employ screening assays
alone when warnings are the only consequence of a positive assay. Such
programs should however use more rigorous procedures when more severe actions
are to be taken.
21 - Can passive inhalation of marijuana smoke lead to a
positive urine even if the person did not smoke a joint?
Answer: Inadvertent exposure to marijuana is frequently
claimed as the basis for a positive urine. Passive inhalation of marijuana
smoke does occur and can result in detectable body fluid levels of THC
(tetrahydrocannabinol, the primary pharmacological component of marijuana) in
blood and of it's metabolites in urine. Clinical studies have shown,
however, that it is highly unlikely that a nonsmoking individual could
unknowingly inhale sufficient smoke by passive inhalation to result in a high
enough drug concentration in urine for detection at the cutoff of currently use
urinalysis methods.
22 - Can time of previous drug use be determined from
analysis of urine?
Answer: Not specifically. Urine specimens positive
for cannabinoids, for instance, signify that a person has consumed marijuana or
marijuana derivatives from within 1 hour to as much as 3 weeks or more (in
extreme cases) before the specimen was collected. Generally, a single
smoking session by a casual user of marijuana will result in subsequently
collected urine samples being positive for 2-4 days, depending on the screening
method employed and on physiological factors which cause drug concentration to
vary. Detection time increases significantly following a period of chronic
use. Determination of a particular time of use is thus difficult.
The same issues would hold for other drugs, although the time after use during
which a positive analysis would be expected might be reduced to a few days
rather than a week or more.
23 - What adverse health effects can be correlated with the
presence of marijuana metabolites in urine?
Answer: No studies have attempted to correlate
metabolites in urine with specific adverse health effects. The presence of
metabolites in urine indicates previous use of marijuana, and use of marijuana,
at least on a chronic basis, is likely to lead to adverse health effects.
Specific effects, however, cannot be correlated with a single urine
concentration of metabolite.
24a - Can the level of "intoxication" of an individual due to
marijuana use be gauged by urinalysis?
24b - Can his or her "use patterns" be determined?
Answer: Impairment, intoxication, or time of last use
cannot be determined from a single urine test. A true-positive urine test
indicates only that the person has used marijuana in the recent past, which
could be hours, days, or weeks depending on the specific use patterns. An
infrequent user should be completely negative in a few days. Repeated
positive analyses over a period of more than 2 weeks probably indicate either
continuing use or previous heavy chronic use.
25 - How long after use can cocaine/ heroin/ phencyclidine/
marijuana be detected by urinalysis?
Answer: Detection times are dependent on the sensitivity
of the assay. The more sensitive the assay, the linger the drug can be
detected. Drug concentrations are initially highest hours after drug
use and decrease to undetectable levels over time. The time it takes to
reach the point of nondetectability depends on the particular drug and other
factors such as an individual's metabolism. The sensitivity of urine assay
methods generally available today allows detection of cocaine use for a period
of 1-2 days. These detection times would be somewhat lengthened in cases
of previous chronic drug use but probably to no more than double these times.
Metabolites of the active ingredients of marijuana may be detectable in urine
for up to 10 days after a single smoking session. However, most
individuals cease to excrete detectable drug concentrations in 2-5 days.
Metabolites can sometimes be detected several weeks after a heavy
chronic smoker (several cigarettes a day) has ceased smoking.
26 - If a urine sample is negative a day after a
positive sample, does this mean the first result was wrong?
Answer: No. Urine concentrations of drugs such as
THC, PCP, or cocaine decrease rapidly with time. Using the Federal cutoff
levels, light or occasional use may only be detectable for 1-3 days.
Therefore, samples collected 1 day apart may show positive on the first sample
and negative on the second sample. The negative second sample cannot be
used to draw any conclusions about the accuracy of the first sample.
Other factors that can change the concentration of
the drug in urine are:
Dilution of the drug by consuming large amounts of
fluids or by use of diuretics variation of the excretion of drug based on the
time of day when the collection takes place.
These factors could result in repeated samples
collected over several days alternating between positive and negative.
27 - How are the results of a urine drug assay expressed?
Answer: Frequently the results of an assay are reported
by the laboratory simply as positive or negative. If a sample is reported
as positive, this means that the laboratory detected the drug in an amount
exceeding the cutoff level it has set for that drug. Different
laboratories using different procedures and methods may have different cutoff
levels. For this reason, one laboratory could determine a sample to be
positive and another determine the same sample to be negative if the actual
amount of drug in the sample fell between the cutoff levels used by the two
laboratories.
Analyses may also be reported quantitatively.
The actual concentration of the drug is expressed as a certain amount per volume
of urine. Depending on the drug or the drug metabolite that is being
analyzed, urine concentrations may be expressed either as nanograms per
milliliter (ng/ml) or as micrograms per milliliter (mg/ml). (There are
28,000 micrograms in an ounce, and 1,000 nanograms in a microgram.)
Cocaine metabolites may be detected in amounts as high as several micrograms in
a heavy user, but the levels of metabolites from marijuana use rarely reach one
microgram per milliliter and are usually expressed in nanograms per milliliter.
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