A man who was on the liver transplant list at Cedars-Sinai Medical Center in Los Angeles has been removed because he was using medical marijuana and did not show up for a drug test.

In order to get back on the list, Norman Smith, who has cancer, must avoid medical marijuana for six months, submit to random drug testing, and undergo counseling, according to the Los Angeles Times.

The article notes there is no standard policy on medical marijuana and transplants. Each transplant center can decide which patients are the best candidates for organs.

Sally Stewart, a spokesperson for the hospital, said marijuana users can be exposed to a type of mold that can cause deadly disease among patients whose immune systems are compromised. They also are at risk of a fatal lung infection after transplantation, she told the newspaper. “We do not make a moral or ethical judgment about people who are smoking medical marijuana. Our concern is strictly for the health and safety of our patients,” she said.

According to the hospital’s policy, if a patient on a transplant list tests positive for marijuana, they can remain on the list if they sign a statement agreeing not to use the drug. If they fail a random drug test or do not show up for one, they are removed from the list.

Smith, whom the newspaper described as “a recovered alcoholic,” said he used marijuana recreationally in the past before he received a prescription for medical marijuana. He has cirrhosis of the liver and previously had hepatitis C. He said he stopped using marijuana in August and is attending Alcoholics Anonymous meetings to satisfy his counseling requirement.