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The recent legalization of marijuana in Colorado and Washington isn't just about people smoking leaves and buds. Among young users, the most popular form of pot is now something called butane honey oil. It's a concentrated marijuana resin. It is legal where marijuana is legal, but its popularity worries public safety officials. That's in part because making the substance can have explosive side effects. NPR's Martin Kaste reports from Seattle.
MARTIN KASTE, BYLINE: There have always been forms of hash oils out there, but these days they're much stronger, thanks to the expertise of people like Jeremy Kelsey.
JEREMY KELSEY: This starting out, this is the pure THC concentrate that comes from the plant.
KASTE: Kelsey's showing off a Pyrex dish that contains something that looks like green syrup. He dabs at it with a toothpick and tries to convey just how much marijuana this represents.
KELSEY: There's pounds literally that went into this dish.
KASTE: Pounds of marijuana bud?
KELSEY: Yeah, yeah. Yes. This is straight flowers that makes this. This isn't leaf or nothing. This is straight flowers.
KASTE: Kelsey runs a medical marijuana store north of Seattle and he calls this syrup pain medication for cancer patients. Recreational users have other names for it: wax, honey oil, shatter or just plain dabs. They smoke it, vaporize it, even eat it. It produces a gut-wrenching high that makes regular pot seem weak, a high that motivates some of them to share their fun on YouTube.
KASTE: Some people like hash oil so much they make it at home. All you need to do is soak the marijuana in some kind of a chemical solvent which extracts the resin. Do-it-yourselfers like butane because you can buy it at the hardware store. But the trouble is butane can blow up.
(SOUNDBITE OF YOUTUBE VIDEO)
UNIDENTIFIED MAN #1: You squish it down and make sure...
(SOUNDBITE OF EXPLOSION)
UNIDENTIFIED MAN #2: The house is on fire. The house is on fire.
KASTE: Yeah, that's on YouTube too. But you could've seen something like that in person if you'd happen to be standing outside a certain building on the south side of Seattle earlier this week. Verner O'Quinn is with the city's bomb squad.
VERNER O'QUINN: It blew out the windows, blew the wall six inches off the foundation in an area, cracked the siding.
KASTE: There's been an uptick in fires caused by people making hash oil, and not just in pot-friendly Washington state. Last year there was a bulletin about the trend from FEMA. Around Seattle, some of the explosions have been happening inside of refrigerators. O'Quinn says people here seem to think that the best place for their marijuana butane marinade is in the freezer.
O'QUINN: Maybe the process works better when it's colder. At some point what happens is it makes its way into the refrigerator or down to where the compressor is. A small spark will set it off and it generally blows the door off.
KASTE: Washington state allows adults to possess up to an ounce of pot. And turning your pot into hash oil isn't illegal per say. But if you're using explosive solvents, you might be looking at a zoning violation at the very least. The state will require commercial marijuana processors to use safer chemicals and equipment. But officials initially balked at allowing hash oil to be sold at all. Randy Simmons runs the state's pot licensing process.
RANDY SIMMONS: We're trying to move as many people out of the illicit marketplace as possible. And in order to do that, if we would have excluded these oils, we would have left a whole lot of the marketplace in the black market.
KASTE: In other words, they decided that the concentrates were just too popular not to legalize. As a compromise they said that it had to be diluted with food or some other substance. But with experience those rules could change. Simmons points out that liquor laws were constantly fine-tuned after prohibition. And he expects that the same may happen with marijuana and its more potent derivatives. Martin Kaste, NPR News, Seattle.