When Weed Explodes, and Why You Shouldn't Try This At Home

An explosion shook a Santa Rosa neighborhood a little before 10:30 p.m. Thursday night, "pancaking" a shed that erupted in flames. The fire quickly spread to surrounding trees and was threatening a nearby apartment complex when firefighters arrived about four minutes later.  The blaze caused one injury, according to police. Jonathan Dubois, 23, suffered second- and third-degree burns.

Fire investigators said several hours of digging through the rubble left in the aftermath turned up evidence of a butane hash oil, or BHO, lab. The product of these do-it-yourself operations is a type of marijuana concentrate that appears to be growing in popularity, according to public safety officials, but the evidence is more anecdotal than statistical.

"Unfortunately, they're becoming a little more common," Santa Rosa Asst. Fire Marshall Paul Lowenthal said, "and it's putting our community at risk."

But what is BHO, how's it made, and how likely is it that a backyard drug lab will turn into a bomb?

Just Add Butane

Well, it's a little more complicated than that, but not by much. There's no shortage of online videos depicting the process of packing a length of 2- or 3-inch diameter pipe with plant material, adding a cap with a small hole to one end, and strapping some coffee filters to the other. Holding the pipe vertically, manufactures insert the can of butane in the capped end and let the liquid butane filter through the marijuana. Butane carrying concentrated THC drips out the coffee filter end into a Pyrex pan.

With a little heat, the liquid butane evaporates, and what's left is sticky, often amber-colored THC concentrate known as butane hash oil, honey oil, dab, shatter, wax or ear wax.

However, the process can quickly fill an area lacking ventilation with butane gas. Then all it needs is a trigger, which could be any appliance that creates a spark or open flame -- even a refrigerator.

"The butane reaches a source that triggers the ignition," Lowenthal said. He's been to four BHO explosion scenes in the past year, and that's just one Santa Rosa fire investigator. "This particular case," he said, "it was pretty destructive."

How Often?

Reliable statistics aren't easy to locate. The Drug Enforcement Administration's San Francisco division, whose territory spans from Bakersfield to the Oregon border, counted one BHO lab in 2013, 92 in 2014 and 56 so far this year.

"There's no requirement for state and local law enforcement to report those statistics to us," DEA spokeswoman Special Agent Casey Rettig said. "How we are collecting them is a very informal and rough system."

Southern California Sen. Tony Mendoza authored a bill signed into law in early August that strengthens state criminal penalties for BHO and other drug manufacturing near occupied residences.

He cites a "spate of explosions throughout California as the result of BHO manufacturing" and two specific examples, a Walnut Creek explosion late last year that injured three and an earlier one in Sacramento that hospitalized two people and displaced 140.

The California Drug Endangered Children Training and Advocacy Center reports much higher numbers, citing 441 THC extraction laboratories located in California between late 2010 and spring of 2014. A dozen children were injured and three died in explosions, according to the center, while 140 adults were injured and 42 died.

The DEA recently arrested a Bakersfield man under suspicion of running a BHO lab. He was charged with maintaining a drug-involved premises, conspiracy and manufacturing and distributing marijuana in the form of hashish oil. He faces a maximum 20-year prison sentence and $500,000 fine.

Special Agent Rettig emphasized that while medical marijuana is legal in California, with ballot initiatives on the way that could legalize recreational use in 2016, anything containing THC is a schedule 1 controlled substance under federal law. Making BHO also carries a drug manufacturing charge.

"We are coming across this with quite a bit more frequency," she said. "They're extremely dangerous, they're highly volatile, and the explosion is absolutely dangerous for those involved and anyone living in that area as well. Depending on the method used, it can be like a pipe bomb ... It's just devastating."

Useful Substance

Despite federal law, California is making moves to legitimize the manufacture of BHO for medical use. The state legislature just passed a package of bills that creates a defined, state-level regulatory scheme that could largely replace the patchwork of local laws currently governing medical cannabis. Gov. Jerry Brown's office played a part in crafting the legislation and is expected to sign it, according to the head of California's branch of the National Organization for the Reform of Marijuana Laws, Dale Gieringer.

Among the potential changes is a provision that would require the state Department of Public Health to issue licenses for the manufacturer of products using volatile solvents.

"It's a very good thing," Gieringer said. "The future of the industry lies in extracts of various sorts. They don't have to be butane extracts; there are other forms."

He said dosage for medical cannabis is much more precise via an electronic cigarette-type device.

"It's much safer than smoking on the lung, and it's better than eating it, where dosage is always a problem," he said, adding that the cannabis e-cigarette cartridges typically contain concentrated THC oil.

He's for the new regulations, and like law enforcement, strongly cautions against making BHO at home.

"What you're dealing with is lighter fluid or the gas you've got in your stove, and it's explosive," Gieringer said. "Yes people are doing it. It's easy and it's stupid and many people are blowing themselves up or starting fires. ... Nobody should do this at home. It should only be done by licensed professionals that know how to deal with dangerous chemicals."