Drug Testing FAQ’s

Drug testing is that the evaluation of a urine, blood, or other sorts of biological sample to determine if the subject has been using the drug or drugs in question. There are many circumstances that will result in drug testing:

• Pre-employment or random, work-related drug testing to spot on-the-job drug abuse
• Drug testing for school or professional athletes
• Post-accident drug testing – a vehicular or on-the-job accident that will have involved human error and resulted in casualties or property damage
• Safety-related – if an employee’s job may lead to questions of safety issues if a judgment or physical ability were impaired

Drug testing is usually done when applying for employment, especially for positions that will involve federal transportation, airline industries, railways, and other workplaces where public safety is of the utmost importance. However, workplace drug testing is now common normally for several U.S. employers to minimize the impact of drug abuse and lower productivity within the workplace. The Surgeon General reported that alcohol and drug abuse, including tobacco costs the economy $524 billion annually. In 1997, it absolutely was reported that 5.4 percent of all workers tested positive for illicit drug use. Many companies may offer employee assistance programs to support substance abuse treatment.

Workplace drug screening is primarily limited to drugs with the potential for abuse, including some prescribed drugs, and alcohol. Prescription drug abuse has been reported as a growing problem within the U.S. Sports drug testing could also be required for college-level and professional athletes. Illegal recreational drugs, performance-enhancing drugs like anabolic steroids, erythropoietin, diuretics, recombinant human growth factors, alcohol, or other drugs could also be required in sports testing.

Pre-employment workplace drug testing usually requires that the applicant provides a urine sample, but can also infrequently require blood, saliva, sweat, or hair. In certain jobs, especially people who require a high level of safety, employees are also subject to random drug screening, as well. Random drug screening may be used in instances of workplace accidents, and if the employer has suspicion that the worker is abusing drugs. Random drug testing may occur without cause for suspicion depending upon company policy.

It is important to make certain that the drug testing occurs at a reputable and licensed laboratory. Any credible drug screening program will involve a two-step process. Initial (immunoassay) and confirmatory (gas chromatography-mass spectrometry [GC-MS]) testing are the methods most typically utilized to check for drugs. Using a combination of both tests allows a high level of sensitivity and specificity, meaning there’s a very low chance for false positives or false negatives.

The immunoassay is performed first and is commonly used as a screening method. If the immunoassay is negative, no further action is required, and therefore the results are reported as negative. If the sample is positive, an extra confirmatory GC-MS analysis is performed on a separate portion of the biological sample. The more specific GC/MS is used as a confirmatory test to spot individual drug substances or metabolites and quantify the number of the substance. Confirmatory tests, like GC-MS should be utilized before reporting positive drug test results.

An applicant will be notified that a workplace drug test prior to employment must take place as part of the application process, and may appear in the laboratory within a specified time frame, for example within 24 hours, to reduce the chance that drugs in their system will appear and go undetected. Applicants are directed to a specific laboratory to submit a sample for drug screening (usually urine). Once at the facility, the applicant must submit a sample at the discretion of laboratory personnel and in accordance with their standard policies. Samples of hair, blood, sweat, or saliva can also be used to screen medication before work, even if it is not routine practice. In laboratory testing, strict practices and standards in the chain of custody are followed to avoid sample collection. This legal procedure requires documentation of each person handling the specimen throughout the trial phase. Some laboratory procedures may require direct visual observation while the specimen is being erased.

Employers may use a standard five-panel trial of “street drugs” that include marijuana (THC), cocaine, PCP, opiates (e.g. codeine, morphine) and amphetamines (e.g., methamphetamine ). Some employers may choose a nine- or ten-panel drug review that includes a variety of prescription drugs, such as oxycodone, benzodiazepines, barbiturates, or propoxyphene. Alcohol can also be screened in the sample. Other recent abuse drugs, such as MDMA (ecstasy) may be included. Which drug test is used depends on the private employer, federal requirements, or other workplace guidelines that may already be in place.

Many variables can affect the amount of time the drug remains detectable in urine or other biological samples, including the half -life of the drug, state of hydration and fluid balance, frequency of use, route of administration, used cut-off laboratory concentration testing to detect the drug, and many other variables. Every person and circumstance is different, and the best way to avoid detecting an abusive drug is to not use the drug.

General guidelines are available for detection times. Many drugs stay in the system from 2 to 4 days, although chronic marijuana use can stay in the system for 3 to 4 weeks or longer after the last use. Drugs with a long half -life, such as diazepam, can also stay in the system for a long period of time. Drugs can be detected in hair samples for up to six months, although urine samples are used for most drug screening tests in the workplace. Examples of drugs that may be detected on hair testing include alcohol, marijuana, cocaine, and amphetamines.

*Note: This table should be used as a general guideline only. Many variables may affect the amount of time that a drug remains detectable in the urine or other biological samples, including a drug’s half-life, the subject’s state of hydration and fluid balance, frequency of use, route of administration, cut-off concentration used by the testing lab to detect the drug, or other variables.

One concern for anyone undergoing a drug test is the possibility of a false positive result. Preliminary tests on diagnostic drugs can often result in a false positive result, although the validation (GC -MS) test greatly reduces the chances of a false positive – reducing the risk to close to zero.

It is important that a person undergoing drug testing complete an accurate history of all prescription, OTC, and herbal medicine use prior to the time of sample collection. Certain ingredients, over-the-counter (OTC) or prescription drugs can result in false positives due to cross-reactivity with other ingredients, although many tests have been modified to avoid those possibilities. For example, poppy seeds and dextromethorphan have been reported to lead to a false positive result for narcotics, and decongestants (ephedrine) have been shown to cause false positives for amphetamines. The body converts codeine to morphine and both substances can be found in the test. On the other hand, if benzoylecgonine, the major metabolite of cocaine is detected, the subject cannot say that the result is a false positive due to the administration of Novocaine, or any other “-caine” drug. Benzoylecgonine is found only in nature as a metabolite of cocaine, and there is no other valid reason that it is present in a drug screen.4 As previously mentioned, validation testing in GC-MS will identify individuals who drug or metabolite in a sample, and virtually eliminate the chance for a false positive result.

Other abnormalities in the urine screen may indicate that the results may be a false negative or the sample means adultery. For example, a low lab creatinine value may indicate that a urine sample is contaminated – either the subject coated their urine by consuming excess water prior to the test, or water was added to urine sample. Creatinine levels are often used in conjunction with specific gravity to determine if samples have been diluted. To avoid this problem, the test lab may color the water in their bathroom blue to prevent the sample from being diluted with water from the bathroom.

Subjects may also try to add certain enzymes to the urine sample to affect stability, but this often changes the pH, which is also tested. The argument of inhaling “passive” smoke from being in a room with people smoking marijuana is invalid, because the cut-off concentrations for lab analysis are set above what can happen in passive inhalation. All of these variables, and more, are viewed in lab analysis, keeping them one step ahead of those trying to foil drug tests.

In some labs, patients who receive a positive result may have the option to pay for an independent examination of the urine sample originally submitted. A new urine sample is not allowed for re-testing because the drug in question may have been excreted from the body at that time.

Drug test results must remain confidential and kept separate from the employee’s regular work file.