Frequently Asked Questions

One of the main reasons is to promote, maintain and improve safety in the workplace. There are many occupations where an individual who is using or abusing drugs may affect the safety of himself / herself, his / her coworkers and the general public.

Secondly, an employer has the right to maintain an efficient, productive and competitive workforce. Drug use and abuse can lead to increased absenteeism, Worker’s Compensation claims, liability insurance rates along with decreased productivity and efficiency.

Drug testing will provide a means of identifying who is using drugs of abuse so that they may be given counselling or treatment before the problem can become serious.

Some employers conduct anonymous general samplings of workers to obtain statistics on drug use which allow them to evaluate the need for a formal testing program.

In selecting a firm to provide drug testing services, visit the laboratory to ensure that it has all of the following important qualifications :


  • Qualified personnel
  • Experience in the analysis for drugs in biological fluids
  • Experience with both external and internal chain of custody procedures to maintain sample integrity
  • Willingness to provide expert testimony
  • Experience testifying at legal proceedings relating to drug testing
  • Documented standard operating procedures
  • The equipment and instrumentation necessary to perform all aspects of testing, especially GC/MS facilities
  • A stringent Quality Assurance / Quality Control System
  • Security of laboratory facilities, samples and results
  • The ability to assist an employer in establishing a program to test for drugs of abuse


Sample collection and sealing is a critical portion of a drug testing program and an area which is likely to be questioned during any legal proceedings.

Sample containers should be provided by the laboratory. Each container must be sterile and sealed prior to use and should be accompanied by a Chain of Custody form.

A Certification / Consent form must be signed by the subject stating that the sample submitted is his/hers and that he/she is aware that the sample is to be tested for the presence of drugs. Urine samples should be collected by a designated collection supervisor who must seal the sample container with a numbered “destruct” seal in the presence of the subject. Sealing is important to protect the individual’s sample from tampering.

Ideally, the sample should be collected in a dry room (one with no running water) thus eliminating the need for a witness to the urination. Samples must be checked by the collection supervisor for temperature, colour and any abnormalities. If a urine sample has just been voided, the sample container will be warm and the urine yellow in appearance. Occasionally, a person may try to provide a sample which is not his/her own, not urine, or that has been altered by the addition of foreign material.

This is the most important area in a testing program. To ensure the integrity of the sample, the following must be observed.

  • Only clean, sterile, sealed containers are to be used for the collection of samples.
  • Once filled, the sample container must be resealed, preferably with a uniquely numbered “destruct” seal which cannot be removed intact once it has been applied.
  • Sample seals must be initiated by the subject and collection supervisor.
  • Sample number and date must be recorded on the chain of custody form.
  • Sealed/Locked shipping containers should be used.
  • Samples should be handled in the laboratory only by authorized, qualified personnel.
  • Sample containers should be resealed after a portion has been removed for analysis.
  • Reanalysis or positive samples from the original container to ensure proper sample identification in the lab.
  • Each step of the collection, sealing, shipping and analysis must be documented with date, time and signature of the person involved. This forms a continuous chain of custody so that the sample’s integrity can be assured at all times.
Confidentiality is assured by the use of uniquely numbered seals rather than subject names for sample identification. The laboratory reports the results using these reference numbers.

The person responsible for receiving the test results should discuss them with the individual in a confidential manner. The Employee Assistance Program or other rehabilitation programs should also be presented at this time.

There are a variety of methods available for the analysis of samples :

  • Enzyme Multiplied Immunoassay Technique (EMIT)
  • Radio-Immunoassay (RIA)
  • Fluorescence Polarization Immunoassay (FPIA)
  • Thin Layer Chromatography (TLC)
  • High Performance Liquid CHromatography (HPLC)
  • Gas Chromatography (GC)
  • Gas Chromatography / Mass Spectrometry (GC/MS)

The techniques are listed in order from least to most expensive. The first four have a similar confidence level with the remaining three increasing in confidence.

Usually, a small portion of a sample is first analyzed by an immunoassay technique to distinguish samples which are potentially positive for drugs from those that are negative. Potentially positive samples must then be confirmed using another portion of the original sample and analyzed by a technique providing a greater level of confidence. The best technique available to the analyst is GC/MS and should be part of any confirmatory process.

Immunuossay Techniques used by laboratories for initial testing purpose will detect the presence of a specific drug above a threshold level with 95% confidence. These techniques use antibodies which recognize the shape of a specific drug and produce a positive result. However, other compounds and drugs which are similar in shape to the drug of interest may also react with the antibody, thus producing a positive result. This phenomenon, called cross-reaction, may potentially lead to a false positive with drugs. For this reason, confirmation using a chemically different technique is essential.

In order to prove beyond a doubt the identity of a drug present in a sample, GC?MS is the only technique which can be used. GC/MS produces a fragmentation pattern of a compound which is reproducible and unique to that compound and hence undeniable identification. This fragmentation pattern is analogous to a fingerprint. GC/MS is the only analytical technique which will withstand legal scrutiny.

In the case of alcohol, confirmation is performed using GC with a Flame Ionization Detector (FID). This is the acceptable technique for positive identification of this drug since it does not produce a characteristic fragmentation pattern.

A false positive occurs when a sample is reported to contain a drug that is not actually present in the sample.

If all protocols listed below are followed, then false positive cannot occur:

  • All steps have been taken to ensure the integrity of the sample.
  • All tests are performed by qualified personnel.
  • Adherence to a stringent quality assurance / quality control program.
  • Confirmation of positives using GC/MS (GC-FID for alcohol only)
  • All documents are checked by two qualified individuals to ensure that there are no typographical errors.
  • All results are reviewed by a qualified supervising chemist before being forwarded to the client.
In preemployment drug testing programs, the following items should be considered.

The protection of the individual from unfair hiring practice is guaranteed by the Canadian Human Rights Act, the Ontario Human Rights Code and other provincial human rights legislation across Canada. It is illegal to discriminate against employment candidates on the basis of a “handicap” or “illness” and most human rights commissions in Canada seem willing to treat alcohol or drug dependence as a handicap. In fact, the Canadian Human Rights Act specifically states that a “disability” includes a “previous or existing dependence on alcohol or a drug”.

An employer must abide by the human rights regulations pertaining to discrimination based upon a handicap, in this case alcohol or drug dependence, unless the handicap interferes with the performance of the essential duties of the job in a safe, reliable and efficient manner. According to the labour law and occupational health and safety regulations, an employer also has the legal responsibility to provide a safe working environment for his/her employees. These two factors can justify the institution of a drugs of abuse testing program in many instances. An employer also has the responsibility to operate a business in such a way as to ensure the continual employment of his/her workers in a competitive market. Therefore, the employer must have his/her employees operating in a “reliable and efficient” manner.

Drug testing for existing employees raises a few additional issues. Existing employees in a unionized workplace are generally protected from fundamental changes to their working conditions under a collective bargaining agreement. In this situation a drug testing program should be instituted as a joint effort between union and management wherever possible.

A positive determination of drug use or dependency does not necessarily constitute grounds for dismissal if the dependency does not amount to a permanent disability making it impossible for the employee to carry out his/her job requirements. Even where this is the case, the employer may owe a duty to shift the employee is capable of performing. In this case, reasonable accommodation might consist of emphasizing the use of rehabilitation programs. Provincial and federal human rights legislation should be considered since the use of grounds of medical or drug related nature as justifiable cause for termination may well lead to a complaint of discrimination. An employer who is considering a drug testing program or who is developing a drugs of abuse policy should review the proposed policy with a legal advisor prior to its implementation.

The following table* illustrates some of the drugs that can be tested for. It also lists common street names, trade names, techniques of ingestion, effects, and how long they remain in the urine (Clearance Time).

* “Coffee, Tea and Me” , Addiction Research Foundation, 1987

* “Facts About Drugs”, Addiction Research Foundation, 1986

* “Compendium of Pharmaceuticals and Specialties, 1987, 22nd Edition, The Canadian Pharmaceutical Association, EMIT Package Inserts, Syva Company, 1984-87

Ethyl AlcoholEthyl Alcohol (Ethanol)EthanolAlcohol, Beer, Liquor, Wine, Liqueurs, Etc.OralDepressantFlushed,dizzy, incoordination, slow reflexes, hangover, headache, nausea, shakiness10-18 Hours
Hydroxy Amphetamines
Methoxy Amphetamines
& Metabolites
& Related Compounds
Methedrine, Ionamin
Bennies, Uppers, Speed, MDA, TMA, PMA, Adam, EveOral, Intravenous (IV)Central Nervous System (CNS) StimulantReduced appetite, increased breathing & heart rate & blood pressure, dilated pupils, dry mouth, fever, sweating, headache, blurred vision, dizzinesss24-48 Hours (a)
& Metabolites
& Related Compounds
Downers, Goof-balls, Barbs, Reds, Red-birds, Red Devils, Blue Heavens, Purple Hearts, RainbowsOralSedative/hypnotics (CNS Depressants)Calmness, muscle relaxation, induced sleep, "high" feeling, slurred speech, staggering, slowed reactions, relaxation of normal emotional controls, can impair skills & judgement, dangerous to drive or perform tasks requiring concentration and coordination when under influence of barbiturates.72-96 Hours (a)
& Metabolites
& Related Compounds
Valium, Rival, others
Librium, Novopoxide, others
Clonopin, Rivotril, others
Dalmane, Novoflupam, others
Hisnosedon, Narcozep, others
Mogadon, Atempol, Mogadan
OralSedative, TranquilizerCalms hyperactivity, tension & agitation, diminished emotional responses, muscle relaxation, reduced alertness, impairment of muscle coordination, perception & intellectual function, dizziness, low blood pressure, fainting, physical dependence48-96 Hours (a)
CannabinoidsTetrahydro-Cannabinol (THC)
& Metabolites,
Other Cannaiboids
Marijuana, Hashish, Hash OilGrass, Hash, Pot, WeedSmoked, OralMood-altering (Psycho-active)Euphoria (high), talk and laugh more than usual, increased pulse, red eyes, perception may be distorted (sound, colour, etc.), impairs attention, short-term momory, logical thinking and ability to drive car or perform other complex tasks.Weeks
CocaineCocaine and MetabolitesCoke, Crack, Snow, Blow, FlakeSnorting (sniffing), IV, Topical, Oral, SmokedCNS Stimulant, Local anestheticEuphoria, increased energy, mental alertness & sensory awareness, reduced need for food, rest & sleep, bizzare, erratic and violent behaviour, accelerated heartbeat, increased blood pressure, breathing & body temperature, pupil dilation, sweating.48-72 Hours (a)
MethadoneMethadone DoxylamineAmidon, DolophineOralAnalgesicEuphoria, reduction of pain, respiratory depression, cyanosis, coma, circulatory collapse48-72 Hours
& Metabolites
Hyptor, Optinoxan, Parest, Somnafac, Sopor, MandraxQualudes, LudesOralSedative, HypnoticSedation, fatigue, dizziness, sleep, euphoria, tingling and numbness in extremities, seisures, respiratory depression7-14 Days
& Metabolites
& Related Compounds
Epimorph, Morphotec, others
Paverol, 292, others
Dilaudid, Hymophan
Hydodan, Robidone, Dicodid
Oxcocet, Oxycodan, others
Levo-Dromoran, Dromoran
SmackOral, IV, Smoked, Intramuscular (IM), Sub-cutaneous (SQ), Snorted, SuppositoriesNarcotic AnalgesicSurge of pleasure (rush), reduced pain, restlessness, nausea, vomiting, drowsiness72-96 Hours (a)
Phencyclidine (PCP)PCP
& Metabolites
& Related Compounds
Angel Dust, Hog, Peace Pill, Horse Tranquilizer, Animal TranquilizerSnorted, IV, Oral, SmokedAnalgesic,
Very diverse effects depending on doses and individual. Increased heart rate, respiration & blood pressure, shallow respiration, flushing, profuse sweating, numbness, incoordination, nausea, vomiting, blurred vision, rolling & watering of eyes, loss of balance, dizziness, convulsions, coma, violent outburts6-8 Days
& Metabolites
Darvon, Progesic, othersOralAnalgesicReduced pain perception, drowsiness, dizziness, nausea, vomiting, constipation, euphoria, excitement, insomnia, itching, skin rashes, CNS and respiratory depression, convulsions7-14 Days
(a) Clearance items may vary depending on drug used, dosage, frequency and individual metabolism.