Cannabis and Commercial Aviation Where State and Federal Transportation Policies Intersect to Provide Passenger Safety

CANNABIS AND COMMERCIAL AVIATION WHERE STATE AND FEDERAL TRANSPORTATION POLICIES INTERSECT TO PROVIDE PASSENGER SAFETY

May 15, 2018

INTRODUCTION. Commercial jet crashes have been well-tracked from 1959 to the present.

Boeing published an annual “Statistical Summary of Commercial Jet Airplane Accidents,”1 which summarizes worldwide operations from 1959–2015. A total of 1,918 accidents involving jet airliners of all types (including cargo) have killed 29,646 aboard and 1,216 on the ground. By comparison, the 2016 National Highway Traffic Safety Administration (NHTSA) reports that

37,461 people were killed in 34,436 motor vehicle crashes in 2016 alone. The magnitude of one year of traffic fatalities is equivalent to 56 years of aviation fatalities.

Piloting a commercial aircraft is considered to be a safety-sensitive duty. In 1991 Congress passed the Omnibus Transportation Employee Testing Act, requiring Department of

Transportation (DOT) agencies to implement drug and alcohol testing of all safety-sensitive transportation employees. Under the larger umbrella of the DOT is the Federal Aviation

Administration (FAA), the Federal Motor Carrier Safety Administration (FMCSA), the Federal

Railroad Administration (FRA), the Federal Transit Administration (FTA), and the Pipeline &

Hazardous Materials Safety Administration (PHMSA) where each agency has its own random drug testing rates (SEE TABLE 1).

After alcohol and tobacco, and excluding caffeine, cannabis is the third most popular recreational drug.2 It is logical to assume, therefore, that some pilots will be at least social users of cannabis. The purpose of this review is to examine the literature concerning the effects of cannabis on pilot performance and flying skill. Aerospace medicine literature consists of only a small number of studies that have examined the role of cannabis in impairing pilot performance, but as state laws change, this feature of “recreational drug culture” needs to be further examined and applied to safety-sensitive occupations.

2 TABLE 1. DOT Agencies Current Random Testing Rates in 2012 and 2018

2018 Random Drug 2018 Random DOT Agency Testing Rate Alcohol Testing Rate

25% Federal Motor Carrier Safety Administration 10% [FMCSA] (was 50% in 2012)

Federal Aviation Administration 25% 10% [FAA]

25% - Covered Service 10% - Covered Service Federal Railroad Administration [FRA] 50% - Maintenance of 25% - Maintenance of Way * Way *

Federal Transit Administration 25% 10% [FTA]

Pipeline & Hazardous Materials Safety 50% Administration N/A [PHMSA] (was 25% in 2012)

SCHEDULE I DRUGS. The Federal Controlled Substances Act (CSA, Title 21 U.S.C. § 811) makes no distinction between the medical and the recreational use of cannabis. The Drug

Enforcement Administration (DEA) is charged with policing drugs and is governed by the Code of Federal Regulations (CFR, Title 21 §1308.11),3 which classifies cannabis and other drugs of abuse using a four-digit Administrative Controlled Substance Code Number (“drug code”).

Marihuana4 (drug code 7360) is in a larger category of drugs called Schedule I drugs, which are characterized as having no medical use.5

Subverting this clean, numerical taxonomy system is the fact that cannabis is a botanical plant composed of more than 200 “cannabinoid compounds,” which have upregulating and

3 downregulating effects at the CB1 and CB2 receptor sites within the human body.6 As recently as

December 14, 2016, the DEA added a new four digit number to include “Extracts of Marihuana.”

The precise definition of Extracts of Marihuana (drug code 7350) is an extract containing one or more cannabinoids that has been derived from any plant of the genus Cannabis, other than the separated resin (whether crude or purified) obtained from the plant.7 The 7350 drug code took effect on January 13, 2017 and is specifically intended to be applicable to cannabidiol (CBD), if it is not combined with other cannabinols. CBD is interesting and of particular note because it is the least psychoactive – and arguably the most medical – of the known cannabinoids. Prior taxonomies focused almost exclusively on ∆-9 tetrahydrocannabinol (THC) and its psychoactive derivatives, but with the emergence of State-sanctioned cannabis industries, federal agencies like the DEA have had to gain clarity both on the bioactive compounds in the plant material as well as extractions of the cannabis plant.

STATE LAWS. Since 1996, twenty-nine states have enacted laws for the medical and recreational use of cannabis. On December 3, 2012, The Department of Transportation Office Of

Drug And Alcohol Policy And Compliance issued a statement clarifying its longstanding policies around the use of cannabis by safety-sensitive employees, including commercial pilots.8 In the guidance document, the DOT makes a well-defined statement that “state initiatives will have no bearing on the Department of Transportation’s regulated drug testing program.” The Department of Transportation’s Drug and Alcohol Testing Regulation (49 CFR Part 40) will not be amended based on state laws. Furthermore, the DOT does not authorize the use of any Schedule I drugs, including cannabis, for any reason.

Were the federal government to unschedule (remove from the controlled substances list) or deschedule (move to Schedule II) cannabis, DOT policy should not change remarkably. Even

4 in the age of cannabis deregulation and legalization, safety should always remain the primary focus. Persons under the influence of any substance lack the judgment the general public desires.

Only a zero tolerance policy removes all doubt from aviophobics and The National Transportation

Safety Board alike. The most clear-cut policy and the only way to enhance rider safety is through complete abstention from cannabis.

FEDERAL AIRSPACE. Like the DEA, the Federal Aviation Administration (FAA) is also regulated by the Code of Federal Regulations (CFR). Section 14 CFR § 120.33(b) expressly prohibits pilots, flight attendants, flight instructors, and air traffic controllers from performing safety-sensitive functions while having a prohibited drug in their bloodstream. This restriction encompasses both cannabis and cannabis metabolites. A pilot who has a verified positive drug test result for cannabis on the required drug screen or a pilot who refuses such testing will be disqualified to hold an FAA-issued medical certificate.

In a July 2009 DOT publication9, Secretary of Transportation, Ray LaHood indicates that:

“Safety is our no. 1 priority at the U.S. Department of Transportation. And a cornerstone of our safety policy is ensuring that transportation providers across all modes – on roads, rails, water, or in the air, over land and underground – employ operators who are 100 percent drug- and alcohol- free.”

Yet, the threshold for the DOT is not zero (per DOT regulations 49 CFR Part 40): it is 50 ng/ml in a urine specimen (SEE TABLE 2). This indicates that there is some tolerance for cannabis use in a safety-sensitive workplace where a zero threshold would indicate zero tolerance for drugs. Global laws around driving under the influence of cannabis serve as a guide for aviation practices and are as varied as the countries themselves (SEE TABLE 3).

5 In the United States we are remarkably comfortable with instances of non-zero thresholds: like blood alcohol content (.08%). Where other countries like the Czech Republic, Brazil, the

UAE, and Bangladesh have all established a zero tolerance approach to alcohol. All 50 states have set .08% blood alcohol concentration (BAC) as the legal limit for driving under the influence (DUI) or driving while impaired (DWI). For commercial drivers (CDL), a BAC of .04% can result in a

DUI or DWI conviction nationwide. For those under 21 years old, there is a zero tolerance limit― where even the smallest amount of alcohol is grounds for a DUI or DWI arrest. Nevertheless, we have chosen to approach intoxication and risk to public safety with some level of acceptability.

TABLE 2. DOT Drug Testing: Initial Cannabis Drug Test Threshold and Confirmatory Testing

Initial Test Analyte Initial Test Cutoff Confirmatory Test Confirmatory Test Concentration Analyte Cutoff Concentration

Cannabis metabolites 50 ng/ml (non zero THCA 15 ng/ml (THCA) levels)

TABLE 3. Driving Under the Influence of Cannabis (Excerpt from Watson et al, 2016)10

6 THE NATIONAL TRANSPORTATION SAFETY BOARD. There are multiple agencies that involved in federal airspace. The FAA is the agency that decides whether planes fly and is commonly thought of as the regulator – they set the rules. The National Transportation Safety Board (NTSB) is the investigator that comes in after an aviation accident to determine what happened and if a pilot was under the influence of some medication or an illicit drug. The NTSB investigates all airplane crashes and may take years to identify “an approved probable cause of an accident.”

Aircraft accident reports outline the circumstances of a crash, eyewitness accounts, and pilot toxicology. Post-accident toxicology reports are a critical part of the investigation process and a finding of tetrahydrocannabinol (THC - the primary active substance in marijuana) or tetrahydrocannabinol carboxylic acid (THC-COOH - an inactive metabolite of THC) can be used to suggest recent cannabis use (SEE TABLE 4). The presence of THC-COOH offers some additional certainty with which to pinpoint the timing of cannabis use to within 3 hours of a crash.

Depending upon the levels, this may even indicate a more recent intoxication. Toxicology information is used to determine if the pilot's judgment and/or abilities were likely to be impaired at the time of the accident.

TABLE 4. A Sample report of NTSB drug testing from flight LAX06LA293

0.0649 (ug/ml, ug/g) TETRAHYDROCANNABINOL (MARIHUANA) detected in Blood 0.0434 (ug/ml, ug/g) TETRAHYDROCANNABINOL (MARIHUANA) detected in Liver 1.2207 (ug/ml, ug/g) TETRAHYDROCANNABINOL (MARIHUANA) detected in Lung 0.1681 (ug/ml, ug/g) TETRAHYDROCANNABINOL CARBOXYLIC ACID (MARIHUANA) detected in Blood 2.5154 (ug/ml, ug/g) TETRAHYDROCANNABINOL CARBOXYLIC ACID (MARIHUANA) detected in Liver 0.313 (ug/ml, ug/g) TETRAHYDROCANNABINOL CARBOXYLIC ACID (MARIHUANA) detected in Lung

WORKING MEMORY AND COGNITIVE EFFECTS. Cannabis (THC) and its metabolites are the most frequently detected substances in workplace drug testing and can last up to 30 days in the body.11,12,13 The effects of cannabis on cognitive function and psychomotor performance are dose- related.11,14,15,16,17 Reduction in motor skills has been described.2,11,15,16,17,18,19 This includes

7 reductions in physical strength, impaired balance, coordination and steadiness.2,18 Complex tasks requiring rapid responses and discriminating judgement are particularly sensitive to the effects of cannabis.16 Studies have also demonstrated that cannabis produces significant impairment of driving performance.20,21,22 It is worth noting that performance degradation is particularly pronounced in inexperienced cannabis users, but is also present in chronic users.

Working memory is extremely important in everyday activities, but especially in aviation activities. Working memory involves the temporary storage of information derived from sensory systems, long-term memory stores, and motor programs. Working memory is a type of stew for the mind: where ideas from the past and the present amalgamate into a decision for use in the present. Complex cognitive tasks require conscious thought, reasoning, and a combination of divided and focused attention.23,24 This all comes from working memory. Cannabis has a well ascribed detrimental effect on working memory function. (Yet, it is this very action on the amygdala that is beneficial in a medical capacity for PTSD patients that seek to address recursive memories and night terrors.)

One interesting study by Meacham et al25 examined the performance of 6 pilots who were classed as “infrequent cannabis users.” After being trained to fly a specific flight sequence using an instrument flight simulator, the pilots were all given either a controlled dose of cannabis or a matched placebo. Each pilot flew the instrument sequence under both cannabis and placebo conditions. The results of this experiment showed that each pilot suffered a significant deterioration in flying performance during the 30 minute period after consuming cannabis, but not after taking placebo.

In their review of the relevant literature, Pope et al found that there is evidence of a residual effect of cannabis on attention, psychomotor tasks and short-term memory during the 12 to 24 hour

8 period following cannabis use.26 This effect may occur after just a single dose of cannabis. The residual drug effects of cannabis appears to consistently involve impairment of performance on tests of focused attention, visual and verbal memory, and visual motor functions.26

TOXICOLOGY. Comprehensive toxicology testing analyzes specimens in blood, urine, and in the brain where concentrations of tetrahydrocannabinol (THC) can be detected.27,28 THC's primary metabolite is also analyzed during toxicology; it can be detected in cavity blood and urine, but not in the brain. In some cases, toxicology testing may occur postmortem at autopsy. There are many considerations in screening for drugs after death. For example, if no THC is detected in a pilot's brain, but it was detected in cavity blood, it is likely that some of the THC resulted from postmortem redistribution. Such an investigation may find no or inconclusive operational evidence of impairment for a pilot – even given the presence of THC metabolites. Given the long half-life of cannabis, although a pilot used cannabis at some time before the flight, there may be no evidence that he or she was impaired at the time of the accident.

THE ROLE OF THE MRO. The Medical Review Officer (MRO) is critical player in safe aircraft operation and public safety. The MRO is a licensed physician who is responsible for receiving and reviewing laboratory results generated by the employer's drug testing program. He or she evaluates medical explanations for drug test results. The MRO must interpret and enforce DOT regulations. Jim L. Swart, who was the Director of the Office of the Secretary of Transportation in

2012, made clear that MROs will not verify a drug test as negative based upon learning that the employee used “recreational marijuana” in a state that has passed “recreational marijuana initiatives” nor will the MRO verify a test result as negative based on information that a physician recommended that the employee use a drug listed in Schedule I of the Controlled Substances Act.

(e.g. “medical cannabis”).29 These expectations are fully outlined for the MRO in the Drug and

9 Alcohol Testing Regulations (49 CFR Part 40) where the DOT makes clear that cannabis, in all forms, remains illegal under federal law and that the DOT expects MROs to treat cannabis, whether used recreationally or medicinally, as illegal.

The implications of medical cannabis use for CDL drivers is also clear, but what about drug tests for employees not regulated by the DOT? The reality is that most MROs follow DOT testing guidelines for all drug tests in an effort to ensure consistency. Even when a non-DOT regulated employee tells the MRO that he/she is certified to use medicinal cannabis, the MRO will nonetheless certify the test as positive. The MRO may include an external note to the employer that the employee claimed medicinal use. However, the MRO will not seek to confirm the employee’s claim or to otherwise determine if the employee is a certified user.

BEST PRACTICES FOR PHYSICIANS AND EMPLOYEES. The Federal Railroad Administration

(FRA) – another safety-sensitive workplace – requires persons being treated by more than one medical practitioner to prove that at least one of the treating medical practitioners has been informed of all prescribed and authorized medications and has determined that the use of the medications is consistent with the safe performance of duties. The FRA offers the following best practice: consider providing physicians with a detailed description of job duties because a title alone can be insufficient. Many employers will provide employees with a written, detailed description of job functions to provide to their doctors.

EMPLOYER RESPONSIBILITIES & THE USE OF PROHIBITED DRUGS. Employer are responsible for all actions of officials, representatives, and service agents who are carrying out the requirements of 49 CFR part 40. This means a safety infraction of any sort becomes both an individual issue as well as a matter of corporate responsibility. The MRO position bridges corporate interests, pilot interests, and the wellbeing of the general public. If an individual has a

10 verified positive drug test result on, or has refused to submit to, a drug test, the individual has not met the requirements for returning to the performance of safety-sensitive duties. Thus, it is not only a positive test that results in suspension of privileges; a refusal should result in the same suspension of duties.

According to an interview with John Linsenmeyer of the FAA Flight Standards Service:

“In general, anyone operating an aircraft for compensation or hire must hold at least a commercial pilot certificate and at least a second-class FAA airman medical certificate. Operators must keep the medical certificate in their personal possession at all times when exercising the privileges for which they are licensed. A medical certificate is valid for five years for pilots under age 40 and for two years for pilots age 40 and over.” There are more areas of nuance covered by the FAA Office of Aerospace Medicine.

EQUITY IN AVIATION & POLICY IMPLICATIONS. It is curious that the DOT accepts a non-zero threshold for cannabis use (i.e. 50 ng/mL as opposed to 0 ng/mL). The presence of second-hand smoke would not account for this deviation from zero nor would a random drug testing schedule.30,31 This threshold is a deliberate choice and creates a grey area where acceptable behavior is less clear-cut than it could be. If safety is, indeed, the number 1 priority at the U.S.

Department of Transportation and if a drug-free workplace is a cornerstone of safety policy, then ensuring that transportation providers across all modes – on roads, rails, water, or in the air, over land and underground – are 100% drug and alcohol free is absolutely critical.

A sensible approach to cannabis for safety-sensitive positions seems wisely set at zero tolerance and without age restriction. The rational part of a teen’s brain is not fully developed and won’t be fully developed until age 25. So age 21 is irrelevant. Age-based policies are not

11 exceptional and are often enacted in the face of contradictory or nonexistent empirical support, but we should be wiser and more evidence-based in this new paradigm of cannabis legalization.32

The only way to level the playing field for employees is through a no-tolerance policy: should an operator wish to work in an industry that serves the public, the individual should closely guard this safety by abstaining from all intoxicants. This is the only way to erase doubt and to create a system that is equitable for all. Furthermore, random drug screening standards should set at the same rate across all safety-sensitive positions. The FRA should be no different than the

FAA. Each agency guided by the DOT should have the same random drug testing rate/schedule.

Why would we prioritize one mode of transportation above another? This policy does not make sense from a safety standpoint; it only seems to make sense from an economical perspective.

Even in the age of non-psychoactive cannabis compounds, like CBD, and the slew of possible health benefits, we need to be all-encompassing in our regulations around cannabis. Even if we could generate a bona fide field sobriety test (i.e. cannabis breathalyzer), the safety-sensitive workplace is distinct and deserves additional protections. Cannabis use of any kind – psychoactive or non-psychoactive, low-dose or high-dose – needs to be strictly forbidden.

Regulating other industries, which are not considered DOT safety-sensitive workplaces, should be considered on their own. Federal Drug-Free Workplace policies and the Controlled

Substances Act are in direct conflict with changing state laws. In turn, employers must create their own policies and procedures to avoid workplace stigma while maintaining standards of conduct and productivity in the workplace. Court cases such as Coats v. Dish Network, where a quadriplegic medical cannabis patient from Colorado was fired by Dish Network in 2010 for taking his medicine off duty in the privacy of his own home, have created situations where two federal policies, The Americans with Disabilities Act (which does not protect the use of medical cannabis)

12 and The Controlled Substances Act, are positioned against one another. These grey areas create antagonistic relationships between employers and employees with serious medical conditions.

Employers and their Medical Review Officers should use drug testing to monitor compliance and create safer workplaces, but this developing area of employment law and wrongful termination litigation puts employers in the position of deciphering relationships between medical patients, federal laws, state medical cannabis programs, and a physician-approved therapeutic option.

CONCLUSION. How can changes in our culture coexist alongside policies protecting public safety? Prior to flying, there is a well-known phrase that aviation crews must wait “12-hours- bottle-to-throttle” (source document: AFI 11-202v3). After 12 hours, sufficient time has elapsed to allow deleterious effects of alcohol to subside whereby crew members are allowed to commence flight duty with a blood-alcohol level one-quarter of that allowed to motorists.

An appropriate “cannabis- to-throttle” time is yet to be determined, either scientifically or administratively (leaving aside the wider social and regulatory question of whether such a rule is acceptable or not). No such option exists for cannabis due to its lipophilic (fat-soluble) metabolites. No tolerance policies, which exceed existing DOT regulations, honor the safety of the traveling public most competitively and clearly. The literature indicates 24 hours as a time limit, but this may well be too short of a time period for the safe operation of an aircraft.

There are opportunities for experimentation and scientific study around the issue of cannabis intoxication; however, commercial pilots should not subject unsuspecting passengers to experimentation. Given that complex tasks such as driving or flying are particularly sensitive to the performance impairing effects of cannabis, until a true threshold of safety has been obtained, only a zero tolerance policy will suffice.

13 REFERENCES.

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3 Historically, the DEA has been asked to comply with DEA Domestic Cannabis Eradication / Suppression Program. Available at: https://www.dea.gov/ops/cannabis.shtml.

4 Various spellings and synonyms of cannabis exist. In each case, the term cannabis will be used unless a specific agency or report has chosen a different term or spelling.

5 Code of Federal Regulations Title 21 §1308.11(d)(23)

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7 Department of Justice, Drug Enforcement Administration, 21 CFR Part 1308 [Docket No. DEA–342] RIN 1117–AB33, Establishment of a New Drug Code for Marihuana Extract

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27 Tetrahydrocannabinol (marihuana) in concentrations of 0.00136 (ug/ml, ug/g) was detected in the blood cavity. Tetrahydrocannabinol Carboxylic Acid (marihuana) in concentrations of 0.0484 (ug/ml, ug/g) was detected in the urine. Tetrahydrocannabinol Carboxylic Acid (marihuana) in concentrations of 0.0021 (ug/ml, ug/g) was detected in the blood cavity.

28 Flight ERA14FA283

29 65 FR 79526, Dec. 19, 2000, as amended at 66 FR 41952, Aug. 9, 2001; 75 FR 49863, Aug. 16, 2010

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Reisfield GM, Shults T, Demery J, DuPont R. (2013) A protocol to evaluate drug-related workplace impairment. Journal of Pain and Palliative Care Pharmacotherapy.;27(1):43-48. http://www.ncbi.nlm.nih.gov/pubmed/23527668. doi: 10.3109/15360288.2012.753975.

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