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There are pesticides in your pot. Here's how to avoid them




A customer pays for cannabis products at Essence Vegas Cannabis Dispensary after the start of recreational marijuana sales began on July 1, 2017 in Las Vegas, Nevada.
A customer pays for cannabis products at Essence Vegas Cannabis Dispensary after the start of recreational marijuana sales began on July 1, 2017 in Las Vegas, Nevada.
Ethan Miller/Getty Images

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For a week now, California has been experiencing daily life with legal recreational marijuana. But the industry struggles with obtaining pesticide-free products.

An NBC investigation last year found that 93 percent of the samples from 15 different Southern California marijuana dispensaries tested positive for pesticides.

Donald Land, a chemistry professor at the University of California-Davis who oversaw the testing at Steep Hill Labs, spoke with A Martinez about the implications for recreational marijuana.

Pesticides in pot

Pesticide regulation in marijuana has been a hurdle in the past, and that's due to its illegal designation at the federal level, Land explained. That will change this year. 

"So this is the first regulation that will be in place for marijuana for anything," Land said. In terms of what types of regulation will be implemented, he added: "There's a list of targets that all labs have to look for, but there are no limits expressed in the regulations yet so that's something that's going to develop."

In other words, as these regulations begin to phase in and become refined, in the meantime there's still the status quo of most of the stuff that's out there hasn't been tested for pesticides.

What pesticides have been found

Myclobutanil, which is used to control mold and fungus, is the most frequently found in pot, Land said. It's often found on fruits and vegetables.

Land added that EPA studies have deemed myclobutanil to not be very toxic if you eat it. But it's less clear what happens if you heat it up and inhale it into your lungs.

"A manufacturer of the product has said it's not to be used on tobacco or cannabis. They came out with that statement last year. And the reason is that when it's heated, it decomposes and one of the decomposition products that it releases is cyanide gas which is very toxic."

The amounts of cyanide gas are small, and it's unknown how toxic it is at that level.

What consumers can do to protect themselves

"Go to a trusted dispensary. Ask them if they're doing safety testing. Ask to see results for the sample that you're getting. The safety testing for cannabis is an expensive array of tests. If they're paying to get those tests, they will gladly tell you that that's what they're doing and show you the results."

But if they refuse to show you results, it may be because they're not testing.

"Unfortunately, at this point and time, less than about one percent of the cannabis being sold in the legal market," said Land, "is actually tested for safety."