Colorado marijuana vape maker recalls 49 products over cancer-linked solvent

Expanded testing rules meant to catch the chemical had not been implemented

StayCon warned dispensaries last week that it was pulling 49 marijuana vape products from shelves because a flavoring compound described in the recall notice as “botanically-derived” contained methylene chloride, a solvent the Environmental Protection Agency has moved to ban for most consumer and industrial uses because evidence links it to cancer. Some of the recalled items, including vapes marketed as Maui Wowie and Grape Gorilla, first appeared on dispensary shelves more than 18 months ago, according to a joint investigation by ProPublica and The Denver Gazette.

Methylene chloride, which can also be used to strip paint, is already prohibited in marijuana manufacturing under Colorado law and is one of 31 solvents the delayed state testing rule was meant to screen for. The EPA in 2024 banned most uses of the chemical, though the U.S. Court of Appeals for the 5th Circuit this month struck down that rule and sent the matter back to the agency for further review. State regulators have also warned that the solvent can be used to cheaply convert hemp-derived CBD into THC, the psychoactive compound in marijuana, and that the resulting product is sometimes falsely labeled and sold as marijuana.

The contamination at the center of the StayCon recall was detected in August during routine screening at Denver-based Bona Fides Laboratory, a cannabis testing firm. Owner David Mathis said he notified both StayCon and the Colorado Marijuana Enforcement Division as soon as his lab found the chemical, six weeks before StayCon issued its recall notice. Mathis criticized regulators for the testing-rule delay, noting his lab had been equipped to conduct expanded screening since the start of July. “How many samples were not tested but have contaminants in them and were passed to the public?” he said.

The Colorado Marijuana Enforcement Division has not issued its own public alert about the recall. Kyle Boyd, a spokesperson for the agency, told ProPublica and The Denver Gazette that the agency “does not comment on investigations” when asked why it had not made the recall public.

The expanded testing rule that would have caught the contamination was supposed to take effect in July, nearly three months before StayCon told dispensaries about its recall. A spokesperson for the Marijuana Enforcement Division said the state public health department, which reviews labs and recommends their certification, told the agency the rule needed more time. Implementation, the spokesperson said, will begin at the end of this month.

The delay leaves Colorado out of step with 24 of the 43 states with regulated marijuana markets, which already screen for the chemicals the state’s rule would have covered. In the interim, contaminated products have continued to reach consumers.

StayCon, the manufacturer behind the recall, did not respond to questions from ProPublica and The Denver Gazette about why its products became contaminated or what it is doing to address the issue.

Even as the expanded testing protocol is set to go into effect, the state has backed away from plans to close a related and longstanding regulatory loophole: marijuana manufacturers in Colorado still get to choose the samples that labs test and the labs that do the testing. Regulators in January said they were considering overhauling those sampling rules to require lab personnel to collect samples, but they backed down after top manufacturers argued the change would be too expensive.

ProPublica and The Denver Gazette reported earlier this year that regulatory loopholes have allowed contaminated marijuana products that pose health risks to remain on dispensary shelves for months, and sometimes years, and that regulators have moved slowly to issue public warnings even after receiving reports of consumer harm. The publications also previously reported on the dangers of methylene chloride as part of an investigation into Colorado’s failure to adopt regulations other states use to keep intoxicating hemp products off marijuana shelves.

A top Marijuana Enforcement Division official acknowledged in a May meeting with industry representatives that the amount of chemically converted hemp being sold as marijuana in the state is greater than the agency has publicly disclosed. State regulators announced in April a plan to crack down on companies that illegally sell cheaper and potentially hazardous hemp products as marijuana, citing potential tax avoidance and “serious risks to public safety.”