Along with criminal concerns, testing positive for marijuana or any other dangerous drug could lead to serious consequences for mariners, such as termination of employment, removal from safety sensitive duties and revocation of merchant mariner credentials.

Even in cases where the US Coast Guard settles marijuana use cases, mariners still must complete rehabilitation and show a year or more of negative drug tests before returning to service.


In addition, despite increasing state legalization and a cultural shift toward greater acceptance of marijuana use and consumption of marijuana-derived products such as Cannabidiol (CBD) oil, the US Coast Guard and the US Department of Transportation (DOT) chemical testing continues to identify as dangerous drug users individuals with significant amounts of delta-9-tetrahydrocannabinol (THC), which is the primary psychoactive ingredient in marijuana.

While CBD cannot cause a positive DOT test, CBD products commonly contain psychoactive THC in enough amounts to cause a positive drug test. Furthermore, once THC gets into a person's system, it can be detected in urine samples for weeks and hair samples for months after its use is stopped.

If a mariner is a cadet making recreational use of marijuana in a location where it is legal at the state level or a master aboard an oceangoing vessel that used legally-obtained CBD ointment to treat bodily aches and pains, the resulting positive drug test will lead to the same negative consequences that can be difficult to overcome.

Unless and until the drug testing system changes, mariners must avoid using marijuana or any products derived from marijuana that may contain THC, such as CBD oil.

The threat to maritime transportation and risk of career disaster are both too great to take the chance

USCG highlighted.