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Black market fears are hampering cannabis waste recycling efforts in California

Or, why you can't drop off your expended 510 carts at the dispensary you bought them from.

HighGradeRoots via Getty Images

As American cannabis has grown from cottage industry to $25 billion-a-year commercial enterprise that employs 428,059 folks nationwide, the product that weed has become now often bears little resemblance from the product that used to be sold raw. Flower, once delivered in sandwich bags, now arrives wrapped in child-safety-locked, plastic-lined mylar pouches; every gram of hash seemingly needs its own glass jar, plastic lid, and cardboard box; and half-gram vape pens must often be dug from three times their own weight in display and security packaging before use. And while most of the outer packaging can be easily recycled, vaporizer cartridges themselves can be far more problematic to dispose of.

Cannabis is more popular than ever in the US — 44 percent of adults have access to it, either medically or recreationally, more than 90 percent of adults support its full legalization, and a 2021 Weedmaps survey suggests that usage has increased by 50 percent since the start of the pandemic. What’s more, edibles and concentrates continue to rise in popularity among all age groups, from boomers to doomers. This increased demand for vape cartridges — both near-ubiquitous 510-threads like those from Rove or more specialized carts like the Pax Era Pods — has led to their increased production and, in turn, their inevitable arrival in American landfills. In California, the nation’s largest legal cannabis market, 510 cartridges are quite popular but, due to the state’s strict hazardous waste disposal regulations, difficult to dispose of in a responsible manner.

On the production side, virtually every ingredient, component, growth medium, nutrient, castoff, trimming, and scrap is carefully destroyed, typically either dismantled on-site or rendered unusable before being shipped to a certified waste facility. At the cultivation level, Taylor Vozniak, Sales and Marketing Manager for California cannabis waste management company Gaiaca, told Engadget, “it would be plants after they've been trimmed, grow medium — that's either going to be soil or rock wool or cocoa husk — any sort of water nutrients or pesticides.”

At the manufacturing stage, the company handles post-production green waste (think, mashed up stems and leaves) as well as hazardous waste like concentrate solvents and failed edible product batches like misshapen canna-gummies or burned weed brownies — the latter must be destroyed on-site to stay within bounds of the California Cannabis Track and Trace (CCTT) system operated by the state’s Department of Cannabis Control. The CCTT extends to the point of sale, meaning that local dispensaries are responsible for seeing returned product and defective merchandise properly destroyed.

“Single-use batteries have been a big sticking point for a while now,” Vozniak said. “We're proud that we can recycle those vape batteries either with or without cannabis.” As it turns out, much of the underlying impetus for the creation of the CCTT system, Vozniak notes, is to prevent this waste from being illicitly harvested and resold. “The overarching way these regulations were written the way they were is to prevent any sort of product going into the black market,” he noted, which is why cannabis by-products, which is what all the stuff above is considered, has to be rendered into inert “waste” before it gets put in the ground. It’s also why your local dispensary doesn’t have a drop-off bin for used cartridges.

Products are handled slightly differently depending on whether they’re THC or CBD-based. “CBD is federally legal,” Vozniak said — so that it can be transported across state lines for disposal, “while THC is state-by-state regulated. A lot of the time you'll see, especially in California, CBD destroyed on site, but I have a client in Dallas who I've been able to just take their product as-is off site to a disposal facility.”

The materials that can be directly recycled or composted, will be. The six-month composting process is sufficient to leach out and fully decay any leftover THC before the material is repackaged and sold as a gardening amendment. Less sustainable materials like used nitrile gloves, non-recyclable or food-contaminated packaging will instead be routed to local landfills and incinerators. But not vape cartridges. Those, along with the Li-ion batteries that power them, are considered e-waste in California so there’s a litany of additional regulatory hurdles to jump through before throwing one away.

“What ends up happening is you'll be able to take [used carts and batteries] to a recycling vendor for a while,” Vozniak said, until “they realize it's a difficult product to deal with, so we'll have to find new vendors.”

Ted Chase points the amount left in his medical marijuana vape cartridge. Photo by Lauren A. Little (Photo By Lauren A. Little/MediaNews Group/Reading Eagle via Getty Images)
Ted Chase points the amount left in his medical marijuana vape cartridge. Photo by Lauren A. Little (Photo By Lauren A. Little/MediaNews Group/Reading Eagle via Getty Images) (MediaNews Group/Reading Eagle via Getty Images via Getty Images)

The difficulty with recycling cartridges lies in their complex construction and mix of materials — woven cloth wicks and aluminum atomizers sealed by plastic walls with rubber o-rings keeping the viscous liquid in place. You can’t very well clean, sort, and disassemble these items by hand; as e-waste, they’re sorted, cleaned and then repeatedly mechanically shredded and resorted into progressively smaller chunks until they’re reduced and separated into their constituent materials. Vape pen batteries, both rechargeable and single-use all-in-one varieties, go through a similar process, Vizniak explains. They’re first statically separated by density, then dipped into liquid nitrogen to instantly freeze and deactivate the lithium ion cells before they’re pulverized with mechanical hammers and further sorted for commodity sale.

If that seems like a whole lot of work for such tiny devices, you’re not wrong. Despite the legal cannabis industry in California existing for less than a decade, much of the verbiage of Prop 54 is already falling out of relevance. “When things were first written, there was a lack of understanding of how the cannabis industry would end up operating,” Vozniak said. He points to all-in-one (AIO) pen battery disposal as one such example.

“We still have to destroy these products on site — and I understand the concern there, they [state regulators] don't want anything going to the black market — but for these all-in-one-pens, there really is no way to destroy them without putting the operators at risk,” he continued. “A lot of times, operators are going to try to destroy these products themselves because Gaica can be on the more expensive side just because of the nature of what we do. It's very labor intensive.”

Vozniak has seen cannabis retailers encase old AIOs in blocks of resin to deactivate them — whole drums of resin-ensconced lithium batteries that no recycler would ever take — in order to comply with the state’s “destroy on-site” order. Vozniak argues that a basic exemption to that rule specifically for cannabis e-waste could, “really help the industry out because that's really what I'm seeing most — out of state as well.”

In addition to contacting their district and state representatives to advocate for regulatory amendments, vape pen users looking to reduce their consumption footprints have a number of options. Refillable 510 cartridges are a thing — they operate just as the single-use canisters from the dispensary do but have a screw-on lid for injecting fresh oil — such as the Flacko Jodye from KandyPens, the SPRK ceramic from PCKT, an all-in-one kit from Kiara Naturals, or the Puffco Plus. Maintaining and cleaning refillable tanks is straightforward and they can easily be topped off using a dab syringe from either your local dispensary or friendly neighborhood drug dealer if you prefer a more homebrewed product.