Fire Chief Michael Hazel said in a statement that the extraction process used butane gas, which led to a dangerous combination inside the home.
“The buildup of butane vapors within the apartment came in contact with an ignition source and an explosion ensued," Hazel said. "The process was being performed on and around an electric stove within the apartment."
The process of extracting THC from marijuana is done to create a substance known as honey oil. Tewksbury Police Chief Timothy Sheehan said that it takes a large amount of marijuana to make a small amount of honey oil, a substance that is potent in low dosages.
“The volatility of the solvents used to extract the THC are subject to explosion at any point in the production methods,” said Sheehan. “We don’t want anyone out there replicating this process because of the life safety issues it creates.”
Hazel said the incident remains under investigation, but added there were a number of full and empty butane cylinders found at the scene of the explosion.
The house exploded at about 9:15 p.m. Tuesday night, blowing out the windows, causing fire to spread to the attic, and requiring three Tewksbury residents who did not live at the home to be transported by helicopter to Boston hospitals.
"This was a very dangerous situation for the residents and the firefighters," said Hazel.
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