Pre-Employment Drug Screening

Pre-employment Drug Screening -What you need to know

What You Should Know About Pre-Employment Drug Testing

Most companies require potential employees to undergo a drug test before finalizing the job offer. This is the policy for well-established and reputable companies, and it is an expected part of the application process for any position.

When a pre-employment drug test is required, the job offer is contingent upon the applicant’s passing the test with a clean result. Here’s what you should know about pre-employment drug testing and who you can turn to for this crucial step in the hiring process.

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  • The Surgeon General, as reported by NIDA, states that alcohol and drug abuse, including tobacco, costs the economy over $740 billion per year. 
  • The rate of positive pre-employment workforce drug screens in the general U.S. population hit a fourteen-year high in 2018, according to a new 2019 analysis from Quest Diagnostics. 
  • Looking at data from close to 9 million urine drug tests from January to December 2018, the overall rate of positivity increased from 4.2% to 4.4% of samples. 
  • This is nearly a 5% increase and the highest level since 2004. 
  • The rate of positive tests from opiates has dropped, from 0.39% in 2017 to 0.31% in 2018, a 21% decrease. 
  • Results from marijuana (THC) testing continue to rise: in the general U.S. workforce, positive results from 2017 to 2018 have gone up from 2.6% to 2.8% of samples, a greater than 7% increase. 
  • Positive results resulting from post-accident testing have also risen: from 7.7% in 2017 to 8.4% in 2018. 
  • Licensed farmers can now grow hemp, as long as it contains less than 0.3% THC. 
  • A recent study found that 20% of CBD products (1 in 5) were contaminated with THC. 
  • Fottrell Q. Americans struggling with opioid addiction miss 50% more work than everyone else.

What is a pre-employment drug test?

A pre-employment drug test is used to determine if a prospective hire uses illicit substances or abuses prescription medication. It may also be used for employees who are returning to work after an injury or absence, at which time it may be referred to as a pre-placement drug test. It is common for employers to require a job candidate to complete a pre-employment drug test, and a job offer may be contingent upon the applicant’s ability to pass. These drug tests typically screen for the use of the following illegal drugs (but can test for others if needed):

Methamphetamines (meth, speed, crank, ecstasy)

THC (cannabinoids, marijuana, hash)

Cocaine (coke, crack)

Opiates (heroin, opium, codeine, morphine)

Phencyclidine (PCP, angel dust)

Why employers should require pre-employment drug testing?

If workplace safety is of the utmost importance to a company, then conducting pre-employment drug tests can help mitigate risks associated with drug misuse. By indicating on a job application that an offer of employment may be contingent on the results of a drug test, an employer can help to deter substance abusers from applying altogether. For occupations that place employees in safety-sensitive environments, pre-employment drug testing is critical. as it can help reduce the number of costly workers’ compensation claims involving drug or alcohol use.

According to the National Institute on Drug Abuse (NIDA):

Drug use may represent as much as a five-fold increase in workplace injury claims


Can you "beat" a Drug Test?

This question is probably one of the most common questions asked to search engines due to the reason stated in the first paragraph. When a great job could be yours, you want to be prepared for the drug test. Drugs remaining in your system depends on many factors:

The person’s metabolism

The drug concentration or dosage

How often the drug was used

The type of drug

The type of drug test

The sensitivity of the test

Drug testing may include several types of specimens, such as:






Hair and nail clippings may provide information from 30 days up to a 6 month timeframe. In urine, drugs may be detected for up to a week to ten days. Blood and saliva will offer more information on immediate drug use, especially if the applicant appears impaired at the time of testing.

It is possible to undermine the test results of a urine drug screening by diluting the urine, purchasing synthetic urine or using an oxidizing agent to break up any detectable amounts in the urine. However, any employer with a comprehensive drug testing program will be able to detect if urine is tainted.


What You Should Know About Pre-Employment Drug Testing

Most companies require potential employees to undergo a drug test before finalizing the job offer. This is the policy for well-established and reputable companies, and it is an expected part of the application process for any position.

When a pre-employment drug test is required, the job offer is contingent upon the applicant’s passing the test with a clean result. Here’s what you should know about pre-employment drug testing and who you can turn to for this crucial step in the hiring process.


What Is Tested in Pre-Employment Drug Screening?

Drug testing before an employment offer is final is usually conducted at an offsite healthcare facility. A urine test is the standard type of drug screening specimen and is the one mandated by the U.S. Department of Transportation (DOT).

The other types of pre-employment drug tests are the saliva test, blood test, and hair test.

A urine drug test can detect a variety of substances that may have been ingested up to five days prior to the test. Cocaine, marijuana, methamphetamine, and opiates are just a few of the illicit drugs that can be detected in a candidate’s urine. The urine can also be screened for other drugs as requested by the employer.

What types of laboratory tests are used for drug testing?

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

The immunoassay is performed first and is often used as a screening method. If the immunoassay is negative, no further action is required, and the results are reported as negative. If the sample is non-negative, an additional confirmatory GC-MS analysis is performed on a separate portion the biological sample. The more specific GC/MS is used as a confirmatory test to identify individual drug substances or metabolites and quantify the amount of the substance. Confirmatory tests, such as GC-MS should be utilized prior to reporting positive drug test results to employers.

What happens during workplace drug testing?

An applicant is notified that pre-employment drug testing will need to take place as part of the application process. They may have to present to the laboratory within a specified time frame, for example within 24 hours, to lessen the chance that drugs in their system will be excreted and undetectable. Applicants are directed to a specific laboratory to submit a sample for drug screening (usually for urine test results).

Once at the facility, the applicant must submit a sample at the discretion of the laboratory personnel and in keeping with their standard policies. Hair, sweat, saliva or blood drug test samples may also be used in pre-employment drug screen, although this is not common practice.

During the laboratory evaluation, strict chain-of-custody practices and standards are followed to prevent adulteration of the sample. This legal procedure requires documentation of each person who handles the specimen through the entire phase of testing.

Certain laboratory procedures may require direct visual observation while the specimen is being voided, although this is not common. This occurs most often when the donor has previously attempted to tamper with a sample.

How long do drugs stay in your system?

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 subject’s state of hydration and fluid balance frequency of drug use route of administration cut-off concentration used by the testing lab to detect the drug.

General guidelines are available for detection times. Many drugs stay in the system from 2 to 4 days, although chronic use of marijuana can stay in the system for 3 to 4 weeks or even longer after the last use. Drugs with a long half-life, such as diazepam , may also stay in the system for a prolonged period of time.

Drug Test Chart and Drug Detection Times* Drug Class Street Name Prescription Brand Name Examples Detection Time in Urine Amphetamine Stimulant speed Dexedrine, Benzedrine up to 2 days Barbiturates depressants / sedatives / hypnotics downers, barbs, reds Amytal, Fiorinal, Nembutal, Donna

How long does alcohol stay in urine?

Results from workplace drug testing are fairly quick and can usually be received in a few days. An employer may also request to have the test done with a rapid test that can provide results on the same day. Negative results are usually received within 24 hours; however, a non-negative screen will require further testing that may take a few days up to one week.

If the initial screen is negative, a medical review officer (MRO) will typically contact the employer with the results. If a positive result occurs, a MRO will contact the applicant for further questioning. It is important to notify the laboratory or MRO of any medications currently in use, including prescription , over-the-counter or herbal medications . The applicant may have to provide proof of a valid prescription and prescriber information for prescription medications.

Can a workplace drug test be false positive or false negative?

A concern for anyone undergoing drug testing is the possibility of a false positive result. Initial screening drugs tests may infrequently result in false positive results, although confirmatory (GC-MS) testing greatly lessens 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 drug use prior to the time of the sample collection. Certain substances, over-the-counter (OTC) or prescription drugs may result in false positives due to cross-reactivity with other substances, although many assays have been reformulated to avoid these possibilities.

Do poppy seeds cause a false positive drug test?

Poppy seeds and dextromethorphan have been reported to lead to a false positive result for opiates. Decongestants ( ephedrine ) have been implicated in causing false positives for amphetamines. The body metabolizes codeine to morphine and both substances may be found upon testing.

What can cause a false positive for cocaine?

If benzoylecgonine, the main metabolite of cocaine is detected, the person cannot claim that the result is a false positive due to Novocaine or any other “-caine” type of drug. Benzoylecgonine is only found in nature as a metabolite of cocaine, and there would be no other valid reason for it to be present in a drug screen. As previously mentioned, confirmatory testing with GC-MS will identify individual drugs or metabolites in a sample, and almost eliminate the chance for a false positive result. (Doering, et al)

Does passive smoke inhalation cause a false positive for marijuana?

“Passive” smoke inhalation from being in a room with people smoking marijuana is not considered valid, as the cut-off concentrations for lab analysis are set well above that which might occur for passive inhalation.

Other abnormalities in the urine screen may indicate that results may be a false negative or that there was deliberate adulteration of the sample. For example: a low creatinine lab value can indicate that a urine sample was tampered with; either the subject diluted their urine by consuming excessive water just prior to testing, or water was added to the urine sample. creatinine levels are often used in conjunction with specific gravity to determine if samples have been diluted. To help avoid this problem, the testing lab may color the water in their toilet blue to prevent the sample being diluted with water from the toilet. subjects may also attempt to add certain enzymes to the urine sample to affect stability, but this often changes the pH, which is also tested.

All of these variables, and others, are looked at in the lab analysis.

In some labs, patients who receive a positive result may have the option to pay for an independent retest of the urine sample that was originally submitted. A new urine sample is not allowed for the retest as the drug in question may have been excreted from the body by that time.

The results of drug testing should remain confidential and kept separate from the regular employee work file.

Will CDB (cannabidiol) Make Me Test Positive for Marijuana?

Cannabidiol (CBD), one of the components found in cannabis, has been more frequently used in the U.S. since the government lifted a restriction on growing hemp. Licensed farmers can now grow hemp, as long as it contains less than 0.3% THC. Hemp is a cannabis plant that has little tetrahydrocannabinol (THC) in its make-up. THC is the chemical in marijuana that leads to the “high”.

CBD is promoted to help with conditions like pain, insomnia, and anxiety. Today, you can find CBD in everything from massage oil extracts, to skin lotions, to gummy bears, and it is easily accessible online or at stores. It is also the primary ingredient in the prescription medication Epidiolex , used to treat seizures in people with Lennox-Gastaut syndrome or Dravet syndrome.

People who are using CBD may wonder if it can affect their drug test? Researchers have found that pure CBD did not cause a false-positive on two commercial drug tests used in the U.S. However, because these products are not regulated by the FDA, they may not always be pure, which could lead to variable results. A recent study found that 20% of CBD products (1 in 5) were contaminated with THC. Another cannabis compound known as cannabinol (CBN) did react with the drug tests, as it is a tetrahydrocannabinol (THC) derivative.

Bottom line: even if your drug test turned up a false-positive for CBD, a confirmatory test would be used to distinguish CBD from other compounds. However, if your CBD product was contaminated with THC, your confirmatory test may have a positive result.

Can Employers Drug Test in States Where Marijuana Is Legal?

Can Employers Drug Test in States Where Marijuana Is Legal?

Yes. Legal rules vary from state to state where marijuana is now legal for recreational or medical use. Also, as marijuana stays in the system over a prolonged period of time , the employee may use marijuana legally, but be drug tested at a later time and lose their job.

In general, marijuana legalization laws in states where it is legal support employers in drug testing for marijuana use and firing people for it. Marijuana use is still illegal under federal law, and many employers prefer to maintain their drug-free workplace policies. However, laws are changing, and some states such as Maine, Arizona, and Minnesota have enacted employee protections. As each state has their own set of laws, it’s usually best to seek legal advice to discuss specific marijuana testing laws prior to employment.

Why Implement a Pre-Employment Test?

When an individual applies to a job they may be subject to a pre-employment drug test once a conditional offer of employment has been made. Pre-employment testing is the most common type of drug testing and is a way for employers to make the best hiring decisions possible. To ensure that an applicant is suitable for the position, especially those in a safety-sensitive working environment Pre-employment drug tests will proactively protect the company and its employees from the negative and potentially harmful effects of an employee that uses drugs on the job. Per a recent study from Current Consulting, the cost of abuse in a safety-sensitive industry is significantly higher than other industries. Their study put a cost to the employer of $50,000 per instance of employee drug abuse.

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