This backgrounder is not intended to discuss the merits of drug testing, or go into extensive details on the scientific considerations in setting up a program. It is simply intended to provide an overview of the main issues so that employers considering including testing as part of their alcohol and drug policy have a better understanding of the key issues.

TESTING AS PART OF A COMPREHENSIVE POLICY

Companies need to make a careful assessment of whether alcohol and drug testing should or should not be included in their overall policy. The introduction of testing in any workplace is a controversial decision, and should be made with full understanding of the role of testing in a comprehensive policy, and consideration of whether it is justified for certain employee groups.

Decisions are needed on who to test, under what circumstances, for what substances, using what technology, and what will be the consequence for failing a test, or refusing to be tested (including confirmed tampering with the sample).

WHO IS SUBJECT TO TESTING: UNDER WHAT CIRCUMSTANCES

Circumstances for testing can include:

• pre-employment or pre-assignment (e.g. to a higher risk position) often now referred to as “certification to a safety-sensitive position” where the requirement to pass a test is one part of the certification process leading to appointment to the position;
• as a condition of assignment to work at a particular site;
• after a significant accident or incident as part of a full investigation;
• with reasonable cause (to believe someone is unfit due to alcohol or drug use);
• on a random basis at a specified rate per year;
• as a condition of continued employment after a policy violation; and/or
• as part of a monitoring agreement after treatment.

Some companies may conclude testing will not play a role in the implementation of their policy. Others may conclude testing should be triggered for all employees under certain circumstances, or for certain groups of employees (e.g. high risk) under other circumstances. Each policy must be absolutely clear on when testing applies, and the procedures which will be used, as well as the justification for its introduction.

WHAT TO TEST FOR

Existing technology has developed methods to accurately test for the presence of a wide range of drugs. Workplace testing programs authorized through the United States Department of Health and Human Services (DHHS) and accepted throughout North America, focus on six substances most commonly associated with abuse in the general population.

The standard testing panel is marijuana, opiates, amphetamines, phencyclidine (PCP), cocaine, and alcohol.

Programs are not limited to these substances if there are problems and grounds to “expand” the slate. For the most part, however, additional drugs are generally only tested for in post treatment situations on the advice of the substance abuse specialist.

TEST PROCEDURES - DRUGS IN URINE

There are three stages to the testing process: sample collection, laboratory analysis, and medical review and reporting of results. All three stages have been strictly regulated in the United States, and these procedures have been accepted in Canada as meeting the highest standard of accuracy and integrity of the process. They are described in the sections that follow, and highlighted in the chart at the end of the section.

• Urine specimens are collected under highly controlled conditions at a designated collection site by trained and authorized personnel who ensure privacy during collection, security and integrity of the sample. Chain of custody documentation follows the sample throughout the process, noting everyone who handles it (with every effort made to minimize the number of persons handling specimens).
  
• Qualified laboratories must meet established scientific and technical guidelines for all drug testing programs, and therefore, only laboratories accredited and certified by the U.S. Department of Health and Human Services are used for this testing program.
  
• After the specimen has been properly collected and forwarded to the laboratory, it is analyzed for the presence of drugs using two steps. The first, an immunoassay test is a screen to determine if a drug is present; if the screening test is positive, a second confirmation test is done using highly technical and accurate procedures and equipment called gas chromatography / mass spectrometry (GC/MS).
  
• A sample will only be identified by the lab as positive if the presence of a particular drug is at or exceeds the cut-off level. Although laboratory equipment is sufficiently sophisticated to enable the identification of even minute traces of many drugs, higher cut-off levels are established to ensure accuracy and consistency in drug identification, and to discount minute nuisance intake as from the passive inhalation of second hand smoke, for example.

The positive levels for the five classes of drug tests are indicated in the table below:

* A ng/ml means nanograms per millilitre. A nanogram is one billionth of a gram.
A millilitre is one thousandth of a litre.
** morphine levels exceeding 2000 ng/ml trigger a further lab test for presence of 6-AM (6-acetylmorphine) at or above 10 ng/ml confirming heroin use; since it is only present for a short time, absence does not verify heroine was not used.

• If the results of the initial test are negative, the lab will advise the company or its Medical Review Officer that the test was negative and no additional tests on the specimen will be done.
  
• If the results of the test are positive, the GC/MS confirmation test is performed; only specimens that are confirmed positive on the confirmatory test are reported positive to the Medical Review Officer (MRO) for review and analysis, which will include discussion with the employee to determine whether there is an alternative medical reason for the results. The critical role of the MRO is outlined below.
  
• The lab will also investigate whether the sample has been tampered with and will provide these results to the MRO.
  
• Only when satisfied that it is a true positive or tampered result will the MRO notify the company’s Program Administrator of this conclusion; otherwise, it will be reported as a negative.

Tests results provide qualitative and quantitative information indicating whether a specific substance is present in the urine. The concentration of a drug in urine is influenced by several factors: dose of the drug taken, how it is taken, frequency of use, time lapse from drug use to urine collection, amount of liquid consumed recently, time elapsed since last urination, time of day and any recent dehydrating exercise.

Different drugs are metabolized and excreted from the body at different rates. There are also differences in individual metabolism that influence the rate of elimination. Generally, the following time intervals for detection of drugs in urine after use at standard cut-off concentrations can be expected. The chart should be used as a guideline only, as retention times differ among individuals according to a variety of factors.

For drugs other than alcohol, a confirmed positive test simply indicates that the drug was ingested recently. Tests for alcohol use (breath) are more specific on the degree and timing of impairment, and can identify whether the person was under the influence of alcohol when the sample was collected through standard calculations equating test results to blood alcohol content.

A positive test confirms that laboratory analysis found the drug at or above the prescribed cut-off level. A negative test either confirms the drug was not found in the sample, or that it was present below the cut-off level.

ALTERNATIVE TECHNOLOGIES

Oral Fluid (saliva) testing technology is now available which will allow efficient collection of a sample and analysis in a laboratory following similar security procedures as those for urine drug testing. Although not widely used in Canada at this time, employers are increasing looking at introducing this alternative technology because it is perceived as less intrusive, and provides a tighter window to recent use of a drug. One certified Canadian laboratory has the technology in place to perform saliva testing at this time, and regulations allowing it for U.S. regulated (cross-border) programs are expected shortly. Although there are “quick tests” for saliva available on the market, these are not accurate and produce false negatives for certain drugs (e.g. fail to identify actual drug presence). Only lab based programs should be used for oral fluid testing.

Point of Collection (“quick”) tests are also beginning to be used under certain circumstances in Canada. Because amendments allowing it for U.S. regulated (cross-border) programs are expected shortly, the manufacturers have developed a higher quality product that is easily administered by trained collectors, and minimizes the possibility of tampering.

Current generation collection cups perform the initial “screen” in the cup and can also test for certain adulterants or evidence of possible tampering. A negative result can be obtained at the collection site. However, if the result is not negative, the sample must be sealed and forwarded to a certified laboratory for analysis in the same way lab-based testing is handled. A result that is not negative should not be perceived as being positive – it only means further analysis is required. Employers who use this technology should only use devices that test for possible adulteration or tampering, or they run the risk of false negative results.

TESTING PROCEDURES - BREATH ALCOHOL

Breath analysis for alcohol use is a widely used and accepted technology because breath is the most easily obtained bodily substance and the results are known within minutes of testing. Current-generation breath-alcohol analyzers have excellent accuracy, precision, sensitivity and selectivity or specificity for ethanol in breath specimens.

The concentration of alcohol in end-expiratory breath accurately reflects the alcohol level in the blood and can appropriately interpret the presence and degree of intoxication or impairment at the time the sample is taken.

Specific training and quality control measures are needed to ensure proper administration of the procedure and calibration of the device. Test results are displayed and confirmation results are printed using an Evidential Breath Testing Device. Collection is handled by a trained Breath Alcohol Technician, generally through an external collection agency; a company representative can be trained to operate the equipment if necessary because of unusual circumstances.

• generally two samples are collected a specific time apart to confirm the blood alcohol correlation;
  
• if the first test result is above the designated cut-off, a confirmation test will be done after a 15 minute waiting period (but within 30 minutes after the screening test) to ensure the presence of mouth alcohol from recent use of food or hygiene products does not artificially raise the test result;
  
• if the confirmation test is different from the initial test, the confirmation results will be considered the final test result, and in all cases, a breath alcohol testing form will be prepared for the company, with a copy for the tested individual; and
  
• breath test results are reported directly by the collector to the company Program Administrator.

TESTING PROCEDURES - URINE ALCOHOL

In those situations when a breath analyzer is not immediately available, alternative technology can be used. Usually a saliva screen is used to “screen out” negative results. If a donor screens positive, a second void urine sample is collected and sent to the lab for analysis using similar procedures for security as noted for urine drug testing. Because the density of urine is different than blood, appropriate calculations need to be made to determine a blood alcohol equivalent for policy administration purposes.

As well, employers should exercise caution in using urine alcohol results for disciplinary purposes, as the result may not necessarily prove impairment at the time the sample was taken even if the cut-off is reached or exceeded. Collection of a second void sample will be more reflective of the current state of impairment then the first sample collected as alcohol may have been stored in the bladder for several hours. Urine alcohol testing requires Medical Review Officer to examine possible alternative reasons for a positive result.

TESTING ACCURACY

The process to collect and analyze breath alcohol samples is fully accurate provided an Evidential Breath Testing Device is used by a fully trained breath alcohol technician (BAT). The science on which urine drug testing rests is equally solid provided the process is handled by trained collectors, there is no break in the chain of custody, a screen positive is confirmed by GC/MS analysis and a qualified Medical Review Officer (MRO) reviews all lab positive, adulterated, substituted, or invalid results with the employee.

Although there has been considerable discussion about false positive test results (where a sample is reported to contain a drug that is not actually present above the cut-off level), any possible error in the sample analysis is eliminated through the two-stage screening process and regular calibration of equipment. To avoid any problem, companies should only contract with labs that meet the highest possible standards and are certified by the U.S. Department of Health and Human Services, with trained and qualified collectors, and with an experienced MRO who is fully independent of the laboratory.

CRITICAL ROLE OF THE MRO

It is the Medical Review Officer’s job to determine if the laboratory result should be verified as positive, adulterated, substituted, invalid or cancelled after dialogue with the donor. Some the issues they must deal with are:

• Second-hand Smoke: It is possible for the passive inhalation of marijuana to result in detectable levels of cannabinoids in urine given sufficient time and intensity. However, research has found that it would be extremely improbable that subjects would tolerate this type of noxious smoke environment for the length of time required to absorb the level of marijuana necessary to show a positive result. The cut-off levels are sufficiently high to eliminate exposure to second-hand smoke as a sole viable reason for a marijuana positive test.
  
• Cocaine is still used in certain dental or medical procedures, which could be verified by the MRO after a cocaine positive finding by the lab.
  
• Medications: Certain legal "over-the-counter" or prescription drugs can show positive for metabolites of tested for substances. For example, certain medications and diet pills may contain components that may be detected in the initial screen as an amphetamine-like drug, but these are properly identified by the GC/MS test or in a confirmed prescription. As such, the result would be reported as negative.

  Codeine (contained in some cold medications) can be metabolized by the body into morphine, and therefore, could show positive for morphine in a test. When morphine is identified, the lab may be asked by the MRO to also look for codeine residues as an indication that the individual did, in fact, take codeine. Also, employees have an opportunity to note on their copy of the chain of custody form any legal or prescription drugs they are taking at the time of collection of the sample and advise the MRO accordingly.

  Donors having codeine or morphine levels at or above 15,000 ng/ml must provide valid proof they were authorized to use or were validly administered a medication. At levels between 2000 ng/ml and 15,000 ng/ml, the MRO must have evidence of misuse/abuse in order to determine if the test is verified as positive.

• Poppy Seeds: Depending on the source, poppy seeds eaten with food (e.g. poppy seed cake) can show positive for opiates but the steps taken to verify test results would eliminate the possibility that ingestion of poppy seeds would be reported as a positive result.

SPECIMEN TAMPERING

Tampering can take place when a person knows in advance that he/she will be asked to provide a sample (e.g. primarily in pre-employment/assignment or regular medical situations) where an attempt to substitute a clean sample is used, or in any situation with the help of an additive to “mask” presence of the drug. Collection agencies and labs are aware of most, if not all, of the methods used to tamper with a sample (e.g. dilute it to move the drug level below the cut-off, use additives to mask the drug, substitute other samples or substances) and take appropriate steps to minimize or eliminate this possibility through the collection procedures and analysis checks. Therefore, there is no requirement for observation at the initial collection stage. However, in the event of confirmed tampering, some companies exercise the option to require observed collection on the next test, and in the case of companies complying with U.S. transportation regulations, there are requirements for observation in certain circumstances.

"The information in this article is not intended to be legal advice, but simply presents an overview of current issues in Canada."

© Barbara Butler & Associates Inc.

SETTING UP A TESTING PROGRAM: KEY QUESTIONS AND ANSWERS
RECENT LEGAL DECISIONS


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Updated 2006