what chemicals are used in growing weed

A lack of approved products isn’t the only obstacle to growing organic ganja. Compost teas and guano-based fertilizers contain too much sediment to pass through the tubes used in soil-free hydroponics systems, so indoor growers like Jack rely instead on standard potting soil and watering by hand. Powerful grow lamps suck down large amounts of electricity—a criticism often raised by certified outdoor farmers, whose weed fetches about 50 percent less on the dispensary market because it isn’t as powerful or visually striking as indoor buds. Though Van Hook doesn’t penalize people who use lamps, he refuses to certify indoor grow-ops powered by dirty diesel generators, which are common in California’s remote northern counties.

So Van Hook founded Clean Green, a certification program for medical marijuana farmers that’s nearly identical to the USDA’s organics program—except that it can’t legally use the term “organic.” Since launching in 2004, Clean Green has certified 80 medical marijuana growers who last year produced 8,000 pounds of cannabis valued at as much as $33 million. It’s the only inspection service aimed at pot smokers who want their ganja to be farmed as safely and ethically as their organic salad greens.

In 2004, California organic farm inspector Chris Van Hook submitted an unusual request to the US Department of Agriculture: He wanted permission to certify a medical marijuana farm as organic. He’d already inspected three pot farms, he says, before word came back that weed couldn’t be organic because it wasn’t a federally recognized crop.

As Van Hook continued his inspection, Jack flipped a switch and triggered a white nova of grow lamps. Van Hook crouched beneath them with a microscope in search of signs of pesticide residue and spider mites on marijuana leaves; a few insects are actually desirable as signs of pesticide-free growing. He went on to check that Jack complied with local pot-cultivation laws, electrical codes, and agricultural sanitation standards. He’s applied a similar checklist to the nine medical marijuana dispensaries that are certified as “processor/handlers,” giving them the right to package Clean Green pot—just as the USDA authorizes Whole Foods to package organic granola.

Despite those benefits, many pot growers and sellers are nervous about letting a third-party inspector take notes that could be used against them by federal law enforcement. Which is why the inside of Van Hook’s van displays a framed copy of his law degree from Concord Law Law School; being a lawyer enables him to keep his notes confidential under attorney-client privilege.

Your weed might be gnarlier than you think. So what’s an eco-conscious stoner to do?

According to Van Hook, Clean Green marijuana doesn’t necessarily sell for more than uncertified medical pot; the trick is knowing where to find it. About 10 California dispensaries offer Clean Green-approved product, including Harborside Health Center in Oakland and Herbalcure Collective in Los Angeles. Van Hook, who charges an average of $1,800 per certification, pitches his services to farmers and dispensary owners primarily as a tool for product differentiation and marketing.

On a recent Saturday afternoon, I accompanied Van Hook, a balding, soft-spoken, 54-year-old, on an inspection of an indoor cannabis growing operation in a house deep in a Northern California redwood forest. He’d asked that I not reveal the name and location of the grower, a fit, clean-cut young father whose day job involves corporate leadership training. It had been about a year since Van Hook had certified his grow-op; just as USDA organic standards require, it was now up for its annual re-inspection.

In the front of a detached garage, Jack deactivated a security alarm system and welcomed us inside. Van Hook was already scribbling notes; he doesn’t certify grow-ops in houses with children, who can ingest buds or be killed in electrical fires, unless the plants are in “detached, locked facilities.” Jack unlocked another door leading to a sealed-off grow room that filled the garage nearly wall-to-wall. The pungent smell of 40 thriving marijuana plants (most of them a variety known as Sour Diesel) mixed with the earthy aroma of a bubbling brew of compost tea, a mix of nutrients and beneficial bacteria that is used as a fertilizer and disease suppressant.

Along a wall full of organic gardening products—a molasses-and-yucca-based soil supplement, an oil from Indian neem trees to control pests—Van Hook spotted an unfamiliar-looking bottle of “natural” fertilizer from a company called Humboldt Nutrients. Like many products marketed to pot growers, its psychedelic label looked like the cover of a Grateful Dead album. “Forget about the Buddhas and the spaceships; I look at the ingredients,” Van Hook said as he picked up the bottle. A USDA-certified input reviewer on Van’ Hook’s seven-person staff would later vet its contents.

Though medical marijuana is legal in 15 states, most of them don’t inspect pot farms for compliance with agricultural laws. Which where Van Hook’s status as an accredited “apples-to-zucchini” USDA-certified organic farm inspector comes in: He’s denied some pot growers Clean Green certification for infractions such a using composted human feces to fertilize plants, growing plants near livestock pens that coat buds in manure dust, or setting off a bug bomb in a grow room shortly before harvesting.

“I just want to do something I believe in,” explained the grower, who I’ll call Jack, as we stood outside his modest bungalow, “and do it as ethically and environmentally consciously as possible.”

Photos by Josh Harkinson.

In practice, medical marijuana is typically greener than pot from your curbside drug dealer, which is often sourced through Mexican cartels or illegal grows in national forests. But the distinction pretty much stops there. Grown under the radar of state and federal agricultural authorities, even “medical” cannabis can be covered in toxic mold, raised in rooms filled with shedding pit bulls, or coated in commercial-grade synthetic fertilizers and insecticides such as phosphate and Diazinon, which can be especially toxic if improperly applied. “Under our program a huge advantage is the patient can be assured that their cannabis is being grown in a legally compliant manner,” says Van Hook. Well, at least “legally compliant” enough for any eco-conscious stoner.

The final stop on Van Hook’s inspection was in a shed where Jack unlocked a metal chest beneath a futon to reveal several plastic “turkey bags” brimming with buds. Some dispensaries commission independent testing on their purchases to check for harmful chemical residues. Van Hook’s field tests are more basic. He pulled out a microscope and searched for signs of hair or mold. “They are beautiful buds; they are immaculate,” he proclaimed, marveling at their gemlike THC crystals. Jack smiled. “You are a medical cannabis patient, aren’t you, Chris? Why don’t you try a little bit?”

Josh Harkinson.

The toxic effects of abamectin after oral ingestions include altered mental status, respiratory failure, and hypotension.

There’s Hope.

Common illegal pesticides found in cannabis products include:

As the cannabis industry continues to evolve, the client-base is evolving with it. The typical cannabis consumers are shifting from the “Cheech & Chong” persona of buying an eighth of anything, into educated, discerning cannabis connoisseurs who demand more from their growers and dispensaries. Many consumers are looking to the marijuana industry to resolve health issues and they are becoming increasingly health-aware, chemical-aware, and cannabis intelligent. This kind of consumer influence in the cannabis industry creates pressure to maintain certain standards for clean, chemical-free products.

The State of Colorado defines what pesticide products are safe to use during the cultivation of marijuana. Currently there are more than 300 different fungicides, insecticides, and miticides allowed for use in the cannabis industry. Although that may seem like a very high number, there are more than 12,000 available pesticides in the state.

Just like any other agriculture industry, the chemicals which commercial cannabis growers use while growing cannabis intended for human consumption must be carefully regulated. In Colorado, reporters at the Cannabist helped bring this problem to light 2015 when they independently tested cannabis concentrate products only to find excessive amounts of residual pesticides in the products they were consuming. Their investigation ultimately l ed to mass changes and new rules in the testing process of cannabis pro ducts.

Between October of 2015 and December 2016, a total of 52 product recalls took place according to the updated list on the Cannabist, with 36 in 2016 alone. However, it appears the numbers are on the decline in 2017 with only 7 recalls for the year so far:

We entered a total of 30 indoor marijuana grow operations (IMGO) with law enforcement investigators in order to determine potential exposures to first responders. Samples for airborne fungal spores, volatile organic compounds, carbon dioxide, carbon monoxide, and delta-9-tetrahydrocannabinol (THC) were obtained as well as the identification of chemicals utilized in the IMGO. The chemicals utilized within the IMGOs were primarily pesticides and fertilizers with none showing high toxicity. Although several of the IMGOs had CO2 enrichment processes involving combustion, CO levels were not elevated. THC levels were identified on surfaces within the IMGOs and on the hands of the investigators. Surface levels ranged from <0.1 μg /100 cm(2) to 2000 μg /100 cm(2) with a geometric mean of 0.37 μg /100 cm(2). THC levels on the hands of officers ranged from <0.10 μg /wipe to 2900 μg /wipe with a geometric mean of 15 μg /wipe. These levels were not considered to be elevated to the point of causing a toxic exposure to responders. A total of 407 fungal spore samples were taken using both slit impactor plates and 400-hole impactors. Both methods identified elevated fungal spore levels, especially during the removal of plants from some of the IMGOs. After plant removal, spore counts increased to levels above 50,000 spores/m(3) with one sample over 500,000 spores/m(3). In addition, we found that there was a shift in species between indoor and outdoor samples with Cladosporium sp. the predominant outdoor species and Penicillium sp. the predominant indoor species. We concluded that the potential increase in fungal spore concentrations associated with the investigation and especially removal of the marijuana plants could potentially expose responders to levels of exposure consistent with those associated with mold remediation processes and that respiratory protection is advisable.