Young cancer patient killed by 'contaminated' medical marijuana

Medicinal marijuana is supposed to cure symptoms of nausea, fatigue, and mood swings in cancer patients.

But for one young man, it cost him his life. 

The patient, from northern California, died from a rare fungal infection believed to have come from a contaminated batch of medical marijuana.

Two doctors began noticing that patients were becoming very sick after smoking the drug and decided to investigate why.

Dr George Thompson, a fungal infection expert with UC Davis Medical Center, said the patients at the time were undergoing very intensive chemotherapy and because of that had compromised immune systems.

About five patients came down with a relatively rare but particularly lethal fungal infection. The doctors said that these patients were relatively young and in winnable cancer battles. But for one man, the infection killed him.

'We thought it was strange to have cases of such a bad fungal disease in such a short amount of time, in a span of two to three months,' Dr Thompson told Daily Mail Online.

Dr Thompson teamed up with Dr Joseph Tuscano, of the University of California Davis Cancer Center, to investigate further. But they had a problem: federal law prohibited them from doing that research at UC Davis, so they joined forces with Steep Hill Laboratories in Berkeley.

Dr Donald Land, who has been analyzing contaminated marijuana for over a decade with plenty of experience finding mold and fungus strains, became their partner. 

He told KPIX 5: 'We sometimes see 20 or 30 percent of our samples coming through the lab significantly contaminated with molds.' 

The team gathered 20 samples of medical marijuana from across California and took them apart. They pulled out a range of dangerous bacteria and fungi which they analyzed down to their DNA.

Dr Thompson said 100 percent of the samples came back with mold and 90 percent had bacteria and fungi - similar to what he had seen in the sick patients.

'The main ones were Klebsiella, E.coli, Pseudomonas, Acinetobacter. All of these are very serious infections for anybody in the hospital. But particularly in the very vulnerable cancer population,' he said.

One of questions this raises is whether the risk is made worse by smoking, which could send pathogens directly into the lungs, which are particularly vulnerable.

Although there isn't a great deal of research on this issue, the doctors believe the infection to be self-inflicted from cannabis use.

A common misconception is that the medicine acquired at dispensaries is safer than recreational marijuana but, according to Dr Thompson, 'it doesn't matter where you get, it's all the same and all has a chance of potentially being infected'. 

Research has shown Colorado - ground zero of marijuana legalization in the US -has cannabis lining store shelves that is much more potent than the weed of 30 years ago. 

But this potency boost comes at a cost—modern marijuana lacks many of the components touted as beneficial and is contaminated with fungi, pesticides, and heavy metals.

Colorado does not yet require testing of marijuana for contaminants. Washington, the second state to legalize recreational marijuana, does require testing for microbial agents.

Testing for E.coli, salmonella, and yeast mold conducted in 2014 resulted in a rejection of about 13 percent of the marijuana products offered for sale.

Andy LaFrate, founder of Charas Scientific - one of eight Colorado labs certified to test cannabis -  told Smithsonian Magazine that his team tested more than 600 strains of marijuana from dozens of producers in 2015.

The team conducted potency tests - the only ones Colorado currently requires - and looked at tetrahydrocannabinol (THC), the psychoactive compound that produces the plant's famous high. 

They found that modern weed contains THC levels between 18 and 30 percent—double to triple the levels that were common in buds from the 1980s.  The team also commonly found fungi and bacteria in the products.

'It's pretty startling just how dirty a lot of this stuff is,' LaFrate said.

'Like ourselves, this plant is living with bacteria that are essential to its survival. In terms of microbial contamination, it's kind of hard to say what's harmful and what's not.

'So the questions become: What's a safe threshold, and which contaminants do we need to be concerned about?'

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