Our recent blog, Employers Get More Backup in Medical Marijuana Fight, got a very big response and some interesting questions. Here’s a quick refresher on the story. A Tractor Supply Company job applicant told the HR department that he legally used medical marijuana to treat HIV/AIDS. The company offered him the job, but quickly fired him when he failed the mandatory drug test. The court ruled in the company’s favor claiming that compelling the employer to keep the employee would essentially be forcing them to break federal law.
In one comment, a reader wrote that he would appeal the case and have the plaintiff’s sample re-tested to see if he was actually under the influence while on the job or just positive for having used the drug. While this is a very important distinction -- and one a lot of people would like to be able to make -- the truth is, right now there is no test that can accurately determine the level of impairment when it comes to marijuana.
In a Science Spotlight, the National Institute of Drug Abuse explained that the chemical profile of THC (the primary intoxicant in marijuana and its metabolites) diminishes very rapidly. While the concentration diminishes quickly, the impairment does not. The speed at which THC is metabolized by frequent users opposed to infrequent users is also an issue that makes testing challenging. According to the institute, the THC concentration in blood samples is an imperfect means for testing a person’s level of impairment. They say there are no current methods that can accurately reflect marijuana impairment.
Marijuana use can be detected in saliva for up to 24 hours after use and up to a month in blood and urine samples, but neither of these help a medical marijuana patient prove they are clean and sober while on the job. This is just one of the critical issues that need to be resolved as we see legalized marijuana ballots approved in states across the country.