High levels of THCa in my finished distillate

Hey guys,

I keep getting higher levels of THCa in my finished distillate product, does anyone know what I might be doing that could cause this?


Not possible… Where are you having the testing done?


Honestly every lab in Colorado has given me results with THCa even one with unactivated CBD In the distillate


Sounds to me like theyre either dealing with cross contamination, pocketing your oil and giving you some bogus results or they dont know how to properly operate their equipment.


For it to even boil from the boiling flask to condense in the head pushs it past the temp of decarbing. User error of contamination.


What levels of THCa are we talking about?

It’s inevitable that there will be trace levels of carboxylated cannabinoids in even a distilled product. Thermal decarboxylation becomes exponentially more difficult as the reaction continues.

I’ve had distillate tested numerous times on TLC plates and the carboxylated cannabinoids are always there, and increase as the spot size increases and the lane becomes overloaded.

A chemical decarboxylation would go to completion, but a thermal one never will. If you’re talking about 0.1% THCa and under, those levels are normal and to be expected.

However, from your post, it seems like you’re suggesting levels much higher than these residual traces which are to be expected.

If that is the case, and we’re talking about THCa levels closer to 1% and above, then you’re either doing something very wrong in your distillation (doesn’t seem very likely or even possible), or it’s analytical lab error (much more likely). Possibly cross contamination, possibly inadequate method (again seems unlikely).

Have you had the distillate quantified with gas chromatography? If a GC result gives a THC level equal to the LC result, plus (THCa * 0.887) then it seems more likely that the THCa content reported by your LC labs is correct.


I tested some distillate a while back it was first pass and my methods needed improving, but it showed some amount of cbc-a present. Really small amount but still it was there.

I cant post a picture of the results but here they are:

74.100% thc
00.224% cbc
00.043% cbc-a
00.236% cbd
03.560% cbg
01.510% thc-v
00.620% cbn

Testing was performed at MB labs in Sidney BC, Canada, by LC-ESI-MS/MS and UPLC/UV with a signal to noise ratio of 0.001. They didnt post rsd numbers but that lab is always on point.


I wonder If we can narrow the operating procedure variables enough in distillation to yielded THCa crystals and sauce ?

I dream of a solventless, low cost, massive scale, clean dewaxed/degummed extraction method, able to process thousands of kg of oil from large outdoor harvests!

Where do you draw the line at solvent?

CBC-a??? Never heard that one before. Probably a combination of isomer acids.

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From what i understand CBC breaks down into CBL. I have seen this in person from a purposely degraded sample on the mass spectrometer. From those tests being a rapid first pass on distillate, I assume there was not enough time to degrade the sample.

If i remember correctly that was on a pretty new summit 2L shortpath, with an e2m30. Oil was a mix of bho from smalls and sugar leaf.

Link to source for info on cbc->cbl

Whoa, how deep is your vacuum and at what temperatures are you distilling? Does the starting material have a lot of, if any, terpenes?