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medical marijuana

Rewind 28 years. I am a newly-minted MRO—i.e., a Medical Review Officer, the federally-defined role for a trained (and what came later, certified) physician to review and interpret workplace urine drug test results. MROs discuss results with tested employees, explore authorized/prescribed controlled substance use and, absent that, report what we call a "verified positives" to their employers. So on this particular day in 1993, I am discussing a particular result with a particular client and asking this seemingly simple particular question:

"Why do you include alcohol in your (non-regulated) urine drug screen panel?"

The somewhat bemused employer representative responds as if the question is not only simple but also one whose answer should be self-evident:

"Well, to find out if the person drinks, of course. Can't have anyone drunk around here, especially with what we do and all the heavy machinery. Why do you ask?"

I respond (with apologies for stating what is obvious now but not so much in 1993):

"Well, for starters, alcohol consumption is legal; also, its presence in urine may reflect something the donor did safely and responsibly (and legally) the night before the test and doesn't necessarily correlate with impairment. But then again, the urine presence of marijuana or cocaine or methamphetamine would not necessarily correlate with impairment, either, but we measure them because they are not supposed to be there without medical authorization (or in the case of PCP/phencyclidine, never at all, because there is no medical reason to use this illegal substance). Alcohol is allowed to be there. The result may tell you nothing."

Richard Donze, DO, MPH
Medical Director of The Occupational Health Center at Chester County Hospital

The client, still bemused but now even getting a little testy, responds: "So what do you suggest we do?"

And I:

"Remove urine alcohol from your drug testing panel. If you think someone may be drunk at work, test their blood (this was before we were doing breath alcohol testing)."

My question in 2021 is whether Occupational Medicine provider-MROs now need to proactively have those same conversations with employers about marijuana in states where this substance has been legalized or at least medically decriminalized. My unsolicited advice is YES! If we don't, we risk looking like we are the ones behind the times because some of our clients have already requested whacking the weed off their panels.

Prior to medical cannabis becoming available in Pennsylvania for certain conditions in February 2018, marijuana positive urine tests generally resulted in some disciplinary action at the workplace—withdrawing the offer of hire, suspension and mandatory rehab or termination. The applicants and employees would frequently lie about their use or claim it was secondhand exposure, but occasionally acknowledge that they formerly used it but hadn't in years. A few honest souls would willingly admit that they actively used and say, essentially, "I was sloppy (or stupid) and you got me."

Since February 2018 the conversations can be very different. Some of the same lying and obfuscation still occurs, but more and more I am finding people that have state-issued medical marijuana cards and provide the documentation at the time of urine collection. Most surprisingly, many others without medical need now freely admit that they use it recreationally, and add that they've already discussed it with their employers and everything is OK. "You got me" has turned into "It's all good."

Conversations with employers haven't changed if they are regulated by a Federal agency, such as the Department of Transportation: in this case it's moot because cannabis use is still federally illegal. Even without that regulatory requirement, some employers still voluntarily imitate the federal zero-tolerance approach unless the person has a documented medical marijuana card. But increasingly we have been seeing more flexible and perhaps even creative approaches to dealing with marijuana positives. One company revealed their unwritten rules about which marijuana positives they let slide (maybe somebody in a clerical position), and which ones they will discipline or withdraw offers of hire (maybe somebody operating heavy equipment). I can't wait to see what might happen if one of those decisions is ever challenged.

But some non-regulated companies are letting them all slide, arguing that given increasing recreational and medical use (for the latter, especially since anxiety disorders were added to Pennsylvania's list of qualifying conditions in July 2019), it's just not practical to reject cannabis users and still expect to consistently hire qualified individuals—especially if their target applicant demographic tends to be individuals in their 20s and 30s, and even more especially with current pandemic-era workforce shortages. And as I say, a few of these companies have actually taken the next logical step to avoid running afoul of their own HR policies and asked us to remove marijuana from their urine drug test panels.

It almost seems as if the medical decriminalization of marijuana use in our State has created a more generally permissive attitude among some employers that are already treating it like alcohol—as if it were fully legal for recreational use, too. Maybe those companies are ahead of the curve in case legalization eventually occurs here, as many cannabis enthusiasts believe is now more than just a "pipe" dream (sorry), at which point marijuana use will indeed become like alcohol use. Alcohol is legal, obviously, and people over 21 are permitted to drink; but employers can require that they not drink on the premises or be drunk at work. It will be essentially the same for marijuana if and when it's legalized, but right now in Pennsylvania it is the same for medical marijuana: the law precludes employers from discriminating against someone in hiring and firing decisions simply because the person possess a state-issued medical marijuana card, but they can require that he or she not use or be under the influence at work.

Then there are times when local governments go even further than the state, as when the Philadelphia City Council passed a new ordinance related to workplace marijuana testing on April 22, 2021. When it goes into effect on January 1, 2022, Philadelphia will be the third jurisdiction in the country (New York City is another) to prohibit marijuana screening of prospective employees as a condition of employment; this will make such testing an unlawful employment practice for certain private employers (along with labor organizations and employment agencies). However, it's not a global prohibition against ALL workplace marijuana testing; for example, employers can still test CURRENT employees (as in fitness for duty/suspected impairment scenarios). Also, individuals in certain jobs and professions can still be tested pre-hire; for example, positions in law enforcement; or involved in the care of children, medical patients, disabled and other vulnerable individuals or any type of work that can impact public health and safety; and predictably, jobs that require a commercial driver's license or are related to federal contracts and/or governed by federal regulations.

There's an interesting and critical distinction between the State law and the new Philly ordinance: the Pennsylvania statute still allows marijuana testing, but constrains an employer's options if the test is positive and the individual has a State-issued medical marijuana ID card; after January 1, 2022 in Philadelphia, unless the job category matches one of the exceptions, the employer can't even test.

Whether other employers in the region (outside of Philadelphia) decide to leave marijuana in their discretionary urine drug testing panels or take it out in anticipation of eventual full legalization, at the very least the current availability of medical marijuana requires some retooling of fitness for duty policies. Again, to keep things simple, we have been advising that employers address medical marijuana the way they have traditionally treated alcohol. But even with that, there will also need to be a few adjustments because of the key differences in assessing impairment due to marijuana use, such as the need for blood THC levels as opposed to breath testing for alcohol, and always in combination with a clinical exam (See Sidebar).

So, is it time to take out those discretionary urine drug screen panels and fire up the gas or electric spinning string trimmers? If you're still asking this question, you are already behind the curve: Stop, look and listen—the weed-whacking has already begun.

SIDEBAR: Guidance on Determining Possible Impairment due to Medical Marijuana Use

General Statement

According to the Pennsylvania Medical Marijuana Law ("PA MMJ Law"), an employer may not discriminate against an employee simply because the employee possesses a valid State-issued Medical Marijuana I.D. card ("MMJ card"), and if such use produces a marijuana-positive urine drug screen. However, an employer can require that someone with a MMJ card not use the substance at work, and can also restrict the employee from performing certain job tasks if the employee is found to be "under the influence" ("UTI") of marijuana as defined below:

Can't-do list per PA MMJ Law (but only if UTI, not just for having MMJ card):

"Section 510.Prohibitions.

The following prohibitions shall apply:

(1) A patient may not operate or be in physical control of any of the following while under the influence with a blood content of more than 10 nanograms of active tetrahydrocannabis per milliliter of blood in serum:

  • Chemicals which require a permit issued by the Federal Government or a state government or an agency of the Federal Government or a state government
  • High-voltage electricity or any other public utility.

(2) A patient may not perform any employment duties at heights or in confined spaces, including, but not limited to, mining while under the influence of medical marijuana.

(3) A patient may be prohibited by an employer from performing any task which the employer deems life-threatening, to either the employee or any of the employees of the employer, while under the influence of medical marijuana. The prohibition shall not be deemed an adverse employment decision even if the prohibition results in financial harm for the patient.

(4) A patient may be prohibited by an employer from performing any duty which could result in a public health or safety risk while under the influence of medical marijuana. The prohibition shall not be deemed an adverse employment decision even if the prohibition results in financial harm for the patient."

Defining UTI due to MMJ

  • Per the PA MMJ Law: Blood (not urine) level of 10 ng/mL of "active tetrahydrocannabis" (presumably this is delta-9-tetrahydrocannabinol, a.k.a. "THC").
  • The American College of Occupational and Environmental Medicine ("ACOEM") feels a lower threshold is more appropriate; in their 2015 "Marijuana in the Workplace" paper, ACOEM said that > 5ng/mL is "likely impaired" even in a chronic user, arguing that 5ng/mL is roughly equivalent to a breath/blood alcohol of 0.04g% that is often used as Fitness for Duty ("FFD") threshold, perhaps because the Federal Motor Carrier Safety Administration uses this level to remove someone from "safety-sensitive duties, which can be a surrogate for a kind of an occupational standard.
  • ACOEM goes on to say that a blood test is recommended to "establish an initial presumption of impairment . . . but may not [necessarily] establish impairment in [any given] individual worker."
  • ACOEM recommends combining the blood test with a "medical evaluation for impairment . . . with consideration of the behavior, which led to the referral for testing."
  • Therefore: A marijuana blood test should only be done in the context of suspected impairment and validated (or not) by a clinical evaluation (a FFD exam), and NOT as a standalone evaluation just because someone reports using MMJ as authorized by a MMJ card (the latter would be discriminatory).

Weakness of using MJ blood levels for determining UTI from a 2014 Journal of Medical Toxicology article:

  • "With more states adding . . . medical marijuana laws . . . driving limits have become an important focus of research."
  • "The degree of ethanol-induced impairment has been used as a standard by which other drugs can be compared."
  • "Ethanol, unlike marijuana, has highly predictable pharmacokinetics and blood alcohol concentrations correlate closely with psychomotor disturbances."
  • "Unfortunately, although . . . elevated . . . THC . . .may suggest a greater likelihood of psychomotor disturbance, undetectable serum concentrations do not rule out impairment."
  • That is, the person may be high with a low THC level, and sober with a high THC level.
  • "Roadside psychomotor testing by drug recognition experts in law enforcement [an analog of FFD evaluations by medical providers in a clinical setting] will continue to play a crucial role in driver impairment cases until a consensus on cannabinoid testing can be reached."
  • Bottom-line reality: Just as with those urine alcohol levels mentioned in the body of the article, urine THC levels do not necessarily correlate with impairment, and while blood levels generally do correlate much more closely and consistently than urine, they aren't perfect either.

Suggested to-do list for non-federally-regulated employers

If one doesn't exist already, create a MMJ policy that includes the following elements:

  • Articulate that under State law, unless federally regulated the employer may not discriminate against an employee simply on the basis of the employee possessing a MMJ card, and perhaps having an abnormal urine drug screen that is positive for marijuana because of the authorized use of that substance; however, the employer can require that the employee not use the substance at work, and not be under the influence as it relates to performing certain safety sensitive duties.
  • Define the types of duties that someone may not do while UTI. This can include the ones listed in the State law and described above if pertinent to the company and potential job duties (e.g., prohibiting mining and working with high voltage would obviously only apply in workplaces that included those activities, but not be generally applicable).
  • In addition, or instead, the employer should make their own list of duties for the more generic categories included in the State law; e.g., activities the employer deems "life-threatening" or that "could result in a public health and safety risk" (see State law excerpt above). Such duties might include activities such as operating hazardous equipment or driving for work, but only if vehicle size is not governed by the Federal Department of Transportation ("DOT"), since if driving that kind of commercial motor vehicle, marijuana use would be prohibited by the federal DOT regulations even if a particular state allowed medical and/or recreational marijuana use.
  • Define a blood THC level that would represent or at least strongly suggest being UTI, especially when combined with a clinical fitness for duty evaluation, similar to setting the UTI level for alcohol, which has this range of options:
    • Employers governed by the federal DOT must use a blood/breath alcohol level of 0.04g%.
    • Some employers that aren't federally regulated use 0.04g% as well because it represents a kind of a standard for safety-sensitive work.
    • Other non-federally-regulated employers may choose to use the State DUI level, which in Pennsylvania is 0.08g%, while others go lower than the DOT, such as 0.02g%.

So for marijuana, employers have a choice to go with the State level of 10 ng/mL which is the most liberal approach, or something more conservative such as ACOEM's 5 ng/mL, or something in between. I advise a discussion with counsel.

  • Establish training programs to help supervisors determine whether or not someone appears to be impaired and thus subject to a clinical fitness for duty evaluation and substance abuse testing, which may already exist as a policy put in place to justify FFD evaluations and/or "for cause"/"reasonable suspicion" urine drug or blood/breath alcohol testing.
  • Establish a process for arranging for a FFD evaluation when someone appears impaired, and define the substance testing scenario IN ADVANCE based on the following questions:
    • Will there will be ALWAYS be substance abuse testing (most likely to "catch" someone but also more expensive), or only if there is clinical evidence of impairment on the physical examination (may miss some substance abusers if they aren't impaired enough to fail the clinical exam, but more economical)?
    • When substance abuse testing is done, will it ALWAYS include all three elements (that is, a urine test to potentially detect 5-10 other controlled substances, a breath alcohol test, and a blood test for marijuana)? or
    • Will the employer determine the type of testing at the time the employee is sent? For example, do (a) a blood marijuana test only if the employee is known to have a MMJ card and/or there is an odor suggesting recent marijuana use; (b) a breath alcohol test only if the employer/supervisor strongly suspects alcohol use; and (c) a general urine drug screen only when the person seems impaired but alcohol is not suspected and there is no known MMJ card.

As always, feel free to contact us at The Occupational Health Center with any questions on your drug testing panels and/or your fitness for duty policies. These waters continue to be choppy, but we are happy to help you keep your corporate ships afloat.

The Occupational Health Center (OHC) at Chester County Hospital has been serving the work-related health care needs of the business community since 1988. For more information about medical marijuana and drug testing, contact 610-738-2450.

Related Information from Chester County Hospital:

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