Looking to see if anyone has insight on how these nasty metals could potentially affect the materials start to finish from decarb to distillation.
I’ve noticed lead, arsenic, mercury, and cadmium in flower COA’s and concentrate COA’s. It is VERY unusual for us to fail for heavy metals, but I am curious how these uniquely different elemental metals can alter extraction/distillation outcomes comparatively to cannabis that exhibits none of these metals.
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This is a great question. Two obvious sources in distillate make sense, metals from hardware leeching into the oils, and organometallic compounds codistilling, except maybe elemental mercury which boils in the right range. Tetraethyl lead supposedly boils at 85 degrees C at 15mm Hg. So I imagine there might be other larger non polar alkyl-metallo complexes in the environment with boiling points in distillate ranges.
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Interesting question. Barring catastrophic contamination, there won’t be much metals in the oil, so unlikely to change bulk properties such as boiling point. Depending on the metal could catalyze reactions, especially in a short path pot where the metal would have plenty of time and temperature to catalyze stuff. But what would or wouldn’t happen is totally unknown to me
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I suppose one could break a mercury thermometer and get enough mercury to change properties, but if you do that and don’t realize it then something is very wrong
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This is occurring, especially with less than equitable growers. Exactly what do you want to know about this
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Yes, in case anyone misreads what I wrote, it’s entirely possible to have toxic levels of heavy metals in oil, only that toxicity can happen at levels far lower than would change bulk properties like boiling point of a solution containing metal contaminants
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The properties of the oil wouldn’t change with ppb of heavy metals, but some organometallo compounds could potentially codistill.
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Concentrating your extract from the flower you are actually concentrating in purities and unwanted compounds
I agree that if I’m seeing these heavy metals from flower to distillate COAs they must either have similar boiling points or being codistilled. I’ve been finding articles that at least identify transition metals as ideal oxidation catalysts…
Makes me wonder…
Metals bind to chlorophyll, I wonder if reducing color will help a bit with some metal contaminants
Very interesting. Would you happen to know the mechanism of this?
I’m very interested in this topic and would super appreciate any insight!
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The mechanism of metals binding to chlorophyll that is
Look at heme and notice where the Fe molecule is bound, chlorophyll binds magnesium in a similar manner through the nitrogen atoms that “ligate” the metal. There is rich organometallic chemistry of metalloporphyrins (heme core) and metallochlorins (chlorophyll core). Some metals are easy to introduce, some much harder.
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Has anyone here failed for heavy metals on distillate not in carts? Some may co-distill but I would think most would not.
I’ve seen BHO cookies fail for lead. So something is coextracting, Tetraethyl Leaf? Yuck
I’m not surprised about co-extraction, my question is co-distillation.
In CBD oil, once. Never seen it again.
Anyone have experience with inorganic pigments?
Realgar, cadmium, minimum, vermilion?
I would bet most, or even almost all metal contamination in distillate or anything post distillation is from contact with metals, not carryover from crude
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Metal trays, metal distillation devices, metal spatulas, scouring pads, etc