In Colorado and other states where recreational or medical pot is legal, there is a tremendous amount of money riding these days on healthy cannabis crops. But unlike, say, a corn farmer, growers in the legal-marijuana industry don’t have a clear understanding yet of which pesticides and fungicides are safe to use – for workers or consumers.
Though the Environmental Protection Agency regulates pesticide use on other crops, it has not tested any for use on marijuana because the plant remains illegal at the federal level.
The result is a regulatory void in which, theoretically, anything goes, according to a joint investigation by Rocky Mountain PBS I-News and the Food & Environment Reporting Network. And given what is known about the chemicals commonly used on marijuana plants, that means a potential public-health hazard for the people who smoke or consume legal marijuana, as well as those who work at the grow operations.
“If we’re going to create a legitimate market, let’s protect those people who are going to be growing and harvesting and processing, just like we would for people who are growing and harvesting apples,” said Andy Baker-White, chairman-elect of the American Public Health Association.
Testing is expensive, scientific evidence lacking
Pesticides have long been a staple of black-market marijuana growers. Legal or otherwise, pests and mold remain a problem.
Tyler D’Spain, co-founder and managing director of Aurum Labs, a marijuana testing facility in Durango, said the growers that test with his company seem to be practicing safe and responsible use of pesticides, but that doesn’t mean others aren’t cutting corners.
“When you have a crop that’s ounce for ounce worth almost as much as gold, people are going to go to pretty far extents to protect that crop,” he said. “It’s a huge area of concern. As far as I can tell, people in this area have a higher level of trustworthiness, but it’s still something I would love to see enforced just out of consumer safety.”
However, D’Spain said testing for pesticides is extremely expensive and difficult. It would cost Aurum an estimated half-million dollars to purchase the equipment necessary to detect pesticides, and without it being required by the state, he said it is completely unreasonable from a financial standpoint.
“Also, I don’t think anyone at this point has the sufficient evidence to say whether or not some amount of x or y pesticide is safe,” D’Spain said. “The state’s wary of forcing new testing without solid scientific backing. It’s just not there yet.”
Molly Rogers, a manager at Acme Healing Center, said the Durango dispensary grows its own product and uses only organic soil and natural additives. But ultimately, she said, consumers should find a grower they trust.
“The best course of action is to ask” about the products, she said. “That’s what’s great about customers coming in. We have the time to have customers sit down and get to know the product we have available for them. They need to make sure they’re getting the best product for themselves.”
Karl Roznai, a budtender at Colorado Grow Co. in Durango, said he has fielded some questions in the past about pesticides.
“It’s on people’s minds for sure,” he said. “People are looking for strictly organic products, but I don’t think anyone around here does that. None in Durango that I know of.”
In Colorado alone, the marijuana industry employs 23,000 people as budtenders, managers or growers.
“We are all trying to play catch-up to an actual agricultural industry,” said Pat Currah, a grow facility manager for Green Dream Health Services, a dispensary and grow operation in Boulder. “It’s an ignorance thing, and it’s no surprise – we aren’t trained, we don’t all know what we are doing.”
One mold infestation that is quickly growing infamous among those working in the cannabis industry is called “powdery mildew.”
“It grows fast,” said Frank Conrad, director of Colorado Green Labs, a private cannabis testing facility in Denver. “It will cover an entire room and destroy the value of that crop.”
One response from the industry has been to use Eagle 20EW, a pesticide that has the active ingredient called myclobutanil. Myclobutanil is known to be safe for human ingestion, and is frequently used on food products such as grapes. However, it is not approved for use on tobacco or marijuana.
“If it’s burned and generates hydrogen cyanide, that’s an entirely different problem,” Conrad said.
Eagle 20EW was frequently cited as a chemical used on pot plants that Denver officials quarantined earlier this year.
The issue, then, is what – and how – to spray.
Pesticides transfer to lungs
In July, the Colorado Department of Agriculture posted a 21-page list of pesticides on its website of those labels that might be safe to use on cannabis.
“We have spent an exorbitant amount of time finding those products with a low enough toxicity to not pose a public-health threat,” said John Scott, the department’s pesticide program manager. But he added that more research is needed before anyone can guarantee that these products are safe or effective. Which leaves workers and consumers in a precarious position.
According to a 2013 study published in the Journal of Toxicology, up to 69.5 percent of the pesticides on a marijuana bud can transfer into the smoker’s lungs. Jeffrey Raber, who directed the study and owns a cannabis testing lab in California, said the risks to consumers and workers are clear. “It’s easy to understand that these compounds are toxic. We’ve studied that ad nauseam,” he said. “That’s why regulations exist for every other item we consume.”
Colorado law requires pesticide testing for cannabis products, but nearly two years into recreational legalization, the state has not begun testing.
“The MED, along with the Department of Agriculture and other state departments, are working very hard on this issue to come up with a process that our licensees can be compliant with,” said Thomas Moore, a spokesman for the agency.
State laws in Colorado also require cannabis cultivators to comply with the Federal Worker Protection Standard to protect employees from acute and chronic pesticide exposure, but the guidelines are complex and enforcement has been slow to materialize.
According to the Department of Agriculture’s John Scott, his agency has inspected only about 100 of the 1,000-plus licensed grow facilities in operation. The Washington Liquor and Cannabis Board, meanwhile, has inspected 381 of the state’s 709 producers and processors, issuing six violations for pesticide misuse.
For now, the primary way Colorado regulators learn of pesticide misuse is through regular building-code inspections by the Denver Fire Department.
Last spring, citing safety concerns about improper pesticide use, the city of Denver quarantined tens of thousands of cannabis plants at 11 of the city’s grow facilities.
Then, in early September, a spot-check investigation and private testing by The Denver Post found illegal levels of pesticide residue were still present on products being sold to consumers, prompting a recall by state and city inspectors.
“We initiated an investigation the very next day after that article came out,” Scott said, explaining how seriously the CDA takes allegations of pesticide misuse.
This article was produced in collaboration with the Food & Environment Reporting Network, an independent, nonprofit news organization producing investigative reporting on food, agriculture and environmental health.
