Five Weeks Into Heavy Metals Testing: Cartridge Q&A
There had been quite a bit of conversation online about how cartridges might impact the testing results for heavy metals. This Q&A with Sonoma Lab Works’ Lab Director, David Chen, addresses some of the questions we have both seen online, and been asked directly.
Q: What parts are consistently in a cartridge? Heating element, mouthpiece, reservoir/container are the necessary parts. Some have a drawing component, such as a cotton-like substance, that helps wick oil from the reservoir to the heating element so that the heating element isn’t being forced to heat all of the oil in the cartridge every time the cart is used– but the oil closest to the heating coil.
A: Broadly speaking, carts are made up of three parts: a reservoir to hold the material, a heating element, and a mouthpiece.
Q: CCELL carts are gaining popularity. How do they differ from standard carts?
A: Rather than have a metal coil as the heating element and cotton as the filter, CCELLs use porous ceramic to act as both the heating element and the absorptive material.
Q: Testing the cartridge vs. the oil? Can a machine that tests organic material (such as flower, oil, or extract) also test the hard components of a vape pen, such as the coil?
A: The ICPMS used to test for heavy metals is capable of testing inorganic material, ie plastics, metals, etc. To test these, they must be reduced to a liquid state, which involves incredibly corrosive chemicals, such as hydrofluoric acid. In order to safely use this kind of acid, specialized safety precautions need to be considered, including specialized add-ons to instrumentation, specialized materials resistant to the acid, and separate waste disposal streams. The ICPMS would need to be configured because the hydrofluoric acid would attack the plastic and copper tubing in our current ICPMS set up. To test the hardware, specialized metal/teflon components would have to be added to prevent corrosion to the actual machine. The costs, safety considerations, and specialization of this kind of analysis makes it prohibitive.
Q: Wicking material: Like a candle – many carts utilize a wicking material such as cotton. What issues may arise from this soft material? Might the composition of the cotton, if it is merged with a synthetic material, or if it was bleached cotton – cause an issue? What questions should people be asking about this component?
A: At this time, I am not aware of any precautions to consider when heating cotton.
Q: Fabrication: Twist off, crimped, pods, disposable single-units. Can you comment of the different styles of fabrication you have seen – especially in regards to sealing?
A: There are two broad types of cartridges, disposable one-time use and separate battery/cartridge units. The separate cartridge units come in twist off, crimp tops, and specialized fittings.
Q: Which style are the most complicated fabrication to re-open?
A: Most of these units can be drained in a vacuum oven once opened. Cartridges that are crimped on must be physically pulled off. We are forced to use a vice and pliers to remove the mouthpiece, allowing the oil to drain. The most difficult of these cartridges to get an opening are specialized fittings types, where the cartridge is “snapped on,” ie the “pod” type cartridges. These require manufacturer specifications on best method to access the oil.
Q: Manufacturer protocols: For lack of a better example, luggage often has factory-installed locking mechanisms. Some are combination dials, others have keys. However, there is a unique area in all that is designed to work with a TSA key – so if the TSA needs to open luggage, they are able to. Is there any system or ‘one size fits all’ way to open carts? Has that been established?
A: The different kinds of cartridges make it difficult to find a “turnkey” solution to open the unit. Personally, if it were up to me, the compliance testing would be performed on the oil prior to filling of the cartridge.
Q: The causes of contamination: Heat and time are the primary aggregates that cause reaction. Can you comment on how long oil sits pre-sale in a cart and how that might cause contamination?
A: Correct, metal leaching into an oil is mostly a physical reaction. Like all reactions, heat and time are the leading factor in all reactions. Terpenes are thought to have a higher affinity for the absorption of heavy metals, especially vs the thicker, processed cannabis oil.
Q: How might contamination might occur after a vape pen is used and the oil has been heated over the course of use? Have you tested a cart over the course of use and found differences?
A: We have in fact been doing controlled experiments to identify the source of contamination. Working with one of our clients, we have tested the same cart before use, shortly after use, and then after prolonged use. We did this to determine what contaminates may appear later after the thermal reactions, and to then use that data to inform decisions on cart fabrication.
Q: Pods? We are seeing a trend of different styles in vaping systems. Have you worked directly with any manufacturers to get their assistance on the best way to open them and extract oil for testing?
A: We make an effort to contact manufacturers directly for the most effective way of opening their proprietary pods as quite a few of our clients use them. Some have given us guidelines, and in fact recommend using a needle to draw out the oil. We have been very mindful about the specs and quality of these needles as it introduces an outside variable to the equation.
Q: Ceramic over metal? Is one inherently better than the other? Have you tested enough yet to know if CCels are passing by any significant margin over cotton/metal coils?
A: We introduced heavy metals testing on December 17th, so we currently have five weeks of test data. At this point, it is too early for us to draw a conclusion, the data pool is just too small. We are actively working with clients to determine if there is a significant difference in metal leaching between the two cartridge types. This is something however that we are watching, and if we find the data points in one direction or another, we would then be in a position to make a recommendation. Consumer safety is paramount.