HealthIndustry

Rolling papers, blunt wraps may harbor heavy metals, pesticides

Published on September 2, 2020
Almost half of flavored blunt wraps surveyed failed lab testing. (Ranta Images, ericb007, Planet Flem/iStock)
Almost half of flavored blunt wraps failed lab testing in a 2020 assay. (Ranta Images, ericb007, Planet Flem/iStock)

Blunt and joint smokers around the world may want to consider spending a bit extra to get higher-quality papers from now on. New research shows a significant amount of papers and blunt wraps are likely tainted with heavy metals and pesticides which can harm your health.

Nearly one in ten rolling papers failed California’s stringent standards for legal cannabis product purity…

Leading California lab SC Labs spent two months this summer testing 118 rolling papers, cones, wraps, and cellulose rolling papers purchased from Amazon and several smoke shops around Santa Cruz.

Nearly one in ten rolling papers (13) failed California’s stringent standards for legal cannabis product purity: including 8 of 20 types of blunt wraps SC Labs tested, and all 3 cellulose-based rolling papers tested. Almost all other rolling papers and cones passed.

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Cypermethrin, 120X the legal limit for lead

Flavored blunt wraps looked extra-suspect. For example, the King Palm Berry Terps blunt wrap contained 7 times the California cannabis testing limit for the pesticide cypermethrin.

Even more gross—the aLeda Cellulose Rolling Paper King Size had 120 times the state’s legal limit for lead. According to the US Environmental Protection Agency, there is no safe level of lead exposure.

Josh Wurzer, study author and president of SC Labs said, “Heavy metals look to be the bigger issue than pesticides,” and “cellulose papers were the dirtiest” of the rolling papers they tested.

Wurzer also said his cellulose paper survey size was too small and he planned to do a follow up study looking at more.

Why are papers failing?

Experts aren’t surprised by the findings. Papers are made of plant material and plants (like cannabis) absorb contaminants from the soil. Paper crops also get fumigated to deter pests. Rolling papers are a $1.2 billion dollar global industry, which is generally less regulated than other segments of the tobacco and cannabis industries, though paper manufacturers must list their ingredients.

SC Labs look began in July, after multiple pre-packaged joints—called “pre-rolls”—tested positive for the pesticide chlorpyrifos, a Category 1 pesticide, which under state law means any detection is a failure.

… quality controls have caught 7,229 total batches deemed unsafe under the Golden State’s world-leading standards.

The dirty pre-rolls did not make it to store shelves. Since legal sales began Jan. 1, 2018, quality controls have caught nearly 7,229 batches deemed unsafe under the Golden State’s world-leading standards. Of 137,922 batches tested, 2,185 have failed for pesticides and 811 for heavy metals. Safety thresholds are set very low, because exposure to heavy metals and pesticides carry known risks. The unknown risks of burning and inhaling contaminants heighten regulators’ concern.

SC Labs knew the cannabis in the pre-rolls had previously tested clean, so they tested the papers.

Licensed by the state Bureau of Cannabis Control, SC Labs tested:

  • 70 rolling papers
  • 25 pre-rolled cones
  • 20 wraps
  • and three cellulose-based rolling papers

Gas and liquid chromatography machines scanned for four metals—lead; cadmium; arsenic; mercury—plus 66 pesticides and 5 mycotoxins. This is the full battery of state testing that every product is subjected to before it lands on a licensed dispensary shelf.

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Overall, SC Labs said it found a lot of trace contamination and some borderline fails.

Not the cool kind of metal: SC Labs finds trace metals in most rolling papers.
Not the cool kind of metal: SC Labs finds trace metals in most rolling papers.

There were traces of at least one heavy metal in 91 out of 101 paper products.

As for pesticides—one in 20 paper packs failed California standards. Nearly one out of five papers—showed trace amounts of bug killer.

Legalization cleans up cannabis

When asked about the criticism that cannabis testing requirements are too stringent and burdensome, Wurzer was quick to say, “California got it right with their regulations by having us test products in final form.”

He commended California’s fast reaction to the discovery that there were elevated levels of lead in cartridges and the work the cannabis industry did to become compliant with testing requirements.

He pointed to Oregon rule gaps where “oils that are clean are then added to cartridges and now test positive for heavy metals.”

Stained: A list of weed rolling papers that fail California standards for inhalation purity. (SC Labs, 2020)
Stained: A list of weed rolling papers that fail California standards for inhalation purity. (SC Labs, 2020)

From tainted vape carts, to pesticide-laden bees wax in topicals, to rolling papers, California voter’s cannabis cleanliness standards are reverberating worldwide.

“This is something that cannabis and paper manufacturers should be aware of,” Wurzer said. “If those paper manufacturers are selling to people in the cannabis industry who use their papers then they need to pay more attention to their quality control.”

Read the full SC Labs report ‘Rolling Papers Tested for Heavy Metals and Pesticides’ on Leafly.

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Mitchell Colbert
Mitchell Colbert
Mitchell Colbert is a freelance journalist who has written for Cannabis Now, Hemp Magazine, Green Flower Media, High Times, the Wine Industry Advisor, and other cannabis- and alcohol-focused publications. He runs political strategy firm Full Spectrum Strategy, where he assists cannabis vaporizer companies make products more sustainable. He's also a lecturer at Oaksterdam University, teaching everything from business management to methods of ingestion. TW: @MitchellColbert | IG: @MitchellRColbert
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