MMCC Issues Potential Lead Contamination Vape Advisory

So I was one of the patients that got this notice late, but ICYMI, the Maryland Medical Cannabis Commission issued an advisory about possible lead contamination in "Used" Vape Cartridges. I'll TLDR it for you here, offer my analysis, the questions I still have, and you can read the official MMCC press release & FAQs for yourself if you want. Ahem.

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Vape cartridges in Michigan tested positive for lead contamination according to their Bureau of Marijuana Regulation back in April. Two recent studies indicate lead used in the heating coils can leach into a cartridge over time. Maryland took the initiative of testing their products and found no evidence of lead contamination...except that they did, if you read the FAQ's first question, when they looked at unnamed Maryland vape carts that had actually been used.

MMCC is requiring lead ("and other heavy metals") testing going forward. However, they acknowledge the problem wouldn't arise until long after compliance testing has taken place, so they want to raise awareness among patients of the risk.

Should I Take This Seriously?

Vape hardware is manufactured in China like everything else. While I wouldn't want to hazard a guess as to exactly how many companies are manufacturing vape hardware, I see the same cartridge designs over and over, here at home and wherever I travel. It can't be that many. Check out the photos I've included for this article from four local companies all using what appears to be the same hardware.

vape hardware potential lead contamination
This one is gLeaf...

In the absence of further studies on specific brands, one can only assume any lead-coiled vapes could be a risk. If you care about your health, that is. I suppose if you're the YOLO live fast die young leave a pretty corpse kinda cat, you go ahead and smoke all the lead you want.

Two studies are not exhaustive by any means. The press release from Johns Hopkins fails to explain what type of devices were tested. It's possible from the description that no cartridges were included, as they found participants from vape stores and conventions- folks that would typically use mods. The study from NIH, on the other hand, comes with a chart that shows lead was found in disposable devices, so this one is clearly relevant for cannabis users, too.

What gives me pause, though, is that both Michigan and Maryland report they definitely found lead, though the MMCC is kinda brushing it off. I'm... gonna have to have a think over this.

MPX Maryland Grandaddy Purp Vape Cart close up photo weed marijuana dc oil
this one is MPX...

Burning Questions

Will MMCC continue to test for lead in used vape cartridges going forward? Would they consider banning lead-based coils entirely if they find more? Why not ban lead coils preemptively, if, as they suggest below, there are no known risks with ceramic coils? Patient safety has to come first, yeah? But the vibe here is totes "welp, we sent 'em an email" and toodle-scooting away.

You can't get your own tested. And even in the case of a recall, you're only entitled to a refund of your purchase. DON'T WORRY! IF YOU SMOKE LEAD THAT WE CAN'T TEST FOR, WE'LL GIVE YOU YOUR MONEY BACK! I mean...I'm not really feeling hugged right now by the MMCC, you know?

But what do you think? Are you gonna keep using vape cartridges after this? You can contact me here and tell me if this changes how you feel about vapes or not. I'll put the results in next week's newsletter!

Phyto DC Vape Cart photo
This one is Phyto...


Linthicum, MD (June 14, 2019) – The Maryland Medical Cannabis Commission (MMCC) is providing this advisory to notify patients and other stakeholders of potential lead contamination of cannabis liquids in vape cartridges following exposure to heat. Following reports in other states of lead leaking into the cannabis liquid in some used vape cartridges, the MMCC initiated an investigation, including testing of Maryland vape cartridges for the presence of lead and other metals. The results indicate that while lead is not present in Maryland vape cartridges at the time of product testing, lead may leach into the product from exposure to the heating coils with use, over time. Medical cannabis patients who medicate by vaping should be aware of this potential contamination, which, if occurring, would occur after compliance testing.

According to a study conducted by Johns Hopkins Bloomberg School of Public Health, lead has been found in several brands of cartridges used for vaping. Although the lead is in the heating coils of the device, over time it can leach into the product. Lead contamination in vape cartridges is not limited to Maryland’s medical cannabis market. The MMCC is aware of medical cannabis markets across the country experiencing the same issues with vape cartridge contamination.

While there is limited research on this topic, multiple studies on e-liquids have discovered elevated levels of lead in vape liquids due to the composition of vape cartridges:

Researchers at Johns Hopkins found minimal amounts of metals in the e-liquids within refilling dispensers, but much larger amounts of some metals in the e-liquids that had been exposed to the heating coils within e-cigarette tanks. The difference indicated that the metals almost certainly had come from the coils. Most importantly, the scientists showed that the metal contamination carried over to the aerosols produced by heating the e-liquids.

Among the samples collected in another study, none of the bottles of e-liquids contained detectable levels of lead, which suggests that lead concentrations in disposable e-cigarettes may be related to the proximity of e-liquid to metal components in the product. There was also a significant difference in lead concentration between cartridge and open wick disposable systems, which suggests that the design of the vape products evaluated in this study contributed to overall lead exposure.

In the interest of public safety, the Commission will issue enhanced laboratory testing requirements to further investigate the potential presence of lead in vape cartridges. Effective immediately all compliance testing for vape cartridges will include a heavy metals analysis. If any vape cartridge exceeds MMCC’s heavy metals testing limits the product will not be made available for sale at licensed dispensaries.

Lori Dodson, M.S. MT (ASCP)
Deputy Director

Rythm Maryland vape cart balance photo
this one is Rythm. All silver base, clear window, black plastic tip.


Do vape cartridges offered for sale in Maryland contain lead?

To date, no finished vape product has tested positive for elevated levels of lead at the time of compliance testing (e.g., prior to distribution or sale). However, reports in other states and a small sample of used vape cartridges tested in Maryland indicate that lead may leach from metal heating coils into the cannabis liquid within the vape cartridge with use, over time. The MMCC has implemented expanded laboratory testing for the presence of lead and other heavy metals. If any medical cannabis finished product is determined to contain elevated lead levels, the product may not be offered for distribution or sale to patients or caregivers.

Has the MMCC ordered a recall of any vape products?

No vape products have been recalled at this time. To date, no medical cannabis finished product in Maryland has tested positive for elevated levels of lead prior to distribution or sale. However, the MMCC has implemented expanded laboratory testing for lead and other heavy metals based on reports of elevated lead levels in vape products available in other states.

If a sample analysis of a batch or lot of medical cannabis, including vape products, reveals elevated levels of lead, the Code of Maryland Regulations (COMAR) 10.62.17 requires a licensee to: (1) order a recall of the batch or lot, (2) notify any patient, caregiver, or dispensary who may have obtained medical cannabis from the batch or lot, and (3) offer and pay any reimbursement for any returned medical cannabis. In addition, if any product test results in elevated lead levels under the newly implemented heavy metals testing requirements, the product may not be offered for distribution or sale.

May a patient test their vape products at a registered independent testing laboratory?

No. Registered independent testing laboratories that conduct compliance testing for medical cannabis products may only test samples obtained from a licensed medical cannabis grower or processor.

Which vape products are potentially impacted?

While there is limited research on this topic, multiple studies on e-liquids have discovered elevated levels of lead in vape liquids due to lead in metal heating coils leaching into the vape cartridge with use, over time. The MMCC is not aware of any heavy metal leaching in vape products that use ceramic components.

If a patient is concerned their vape product may contain elevated levels of lead are they able to return the product?

The MMCC has not ordered a recall of any vape products. Concerned patients or caregivers may contact the licensed dispensary where the product was purchased to determine how the unused vape product may be returned for disposal.

(all emphasis mine)