Bummer news for pot smokers: Up to 70 percent of the pesticides found on a marijuana bud can end up in the smoke you’re inhaling. That’s according to recent research conducted by Jeffrey Raber, who holds a PhD in chemistry from the University of Southern California and operates a medical cannabis testing laboratory in L.A.

The Eureka Times-Standard reports:

“I think that what’s so alarming to us is that such a huge amount of pesticide material could be transferred,” Raber said. “And, you have to consider that when you inhale (something), it’s much like injecting it directly into your blood stream.” …

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Raber said it’s important to remember that smoking a marijuana bud that’s been sprayed with chemicals is far different than eating a non-organic tomato. First and foremost, he said, there are no controls over what’s sprayed on marijuana crops. And, while most people would rinse off a tomato before eating it, they can’t wash a bud before putting it in their pipe. The body also has filters in place for things that are ingested, he said, but not for what’s inhaled.

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“You don’t have the first pass metabolism of the liver,” he said. “You don’t have the lack of absorptivity going through the stomach or the gut lining. It’s a very different equation when you’re inhaling.”

Pot farms are notorious for heavy use of pesticides, and even ones selling to legal medical marijuana dispensaries often go heavy on the toxic chemicals.

Humboldt County Sheriff Mike Downey said his deputies have been finding massive amounts of high-powered pesticides at marijuana gardens throughout the county, many of which have posted medical marijuana recommendations — meaning the marijuana grown there could be heading for collectives and, ultimately, to patients.

“I would be very concerned if I were a consumer,” Downey said.

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Our takeaway: Go organic. And if you’re not sure of the provenance of your pot, take it brownie form.