Whos got the lowest THC LOD

Have a big overseas client that wants to be absolutely certain the isolate they will be purchasing will contain the lowest amount of THC possible. Anyone know who can test for D9 D8 and THCA down to the PPM or even less? As always any help is greatly appreciated.

Ppm is calculated

I would go to @kcalabs for their LC testing. If you pay extra they’ll also do GC testing which can be more sensitive

edit- not more sensitive but more selective. Thank you for the correction kca


I use @kcalabs on a fairly regular basis. Their LOD is normally around 84 ppm. This customer is requesting under 1ppm if possible. I haven’t reached out to KCA yet. Im actually doing a trade show via zoom right now and this issue just came up. Its a very large buiness one of the guys keeps trying to get his boss to add cbd skus but the boss is very worried about thc as its heavily regulated. I know this is a very very low LOD. Ive tested at more labs than I care to think about and haven’t heard of anything this low.

Sorry test down to a single ppm. You can put you spoon away but thank you.

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That seems high for MS testing

I think i was looking at a hplc result.

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Pay for additional MS testing, it’ll be ppb instead of ppm


Sweet thanks for the help.

1ppm= 0.0001%, that’s fn low.

The “in vial” loq on most hplc instruments is about 0.5ppm. Meaning the lab would only be able to dilute your sample 2x to get an loq of 1ppm. Most labs would want to dilute samples by at least 100x depending on matrix.

If you are asking to test solid cbd isolate at only 2x dilution… I don’t think that is even going to go into solution. And even if it does dissolve, I’d be wary of injecting it onto a column at such a high cbd conc.

Maybe 10ppm/.0.001% loq (20x dilution) would be more feasible. It would still be a hard sell, but you could ask a lab. Just know it would be a special favor and expect an up charge.


Thanks for that. I hadn’t considered that issue. Definitely willing to pay extra as this may lead to a large account .


You sure you want the spoon put up? 1ppm THC or less CBD seems like quite the challenge I’d think. Lowest ppm for sure can be calculated now using the decimals was all I was trying to assist! Have a nice morning y’all!


The GCMS is more selective and less sensitive than the LCMS.

We can test below 10ppm on LCMS.

The trouble is trying to eliminate cannabinoid contamination in a lab that tests cannabinoids.


Hey I always appreciate the help. I guess I should have thrown an lol in after the spoon comment. Didn’t mean to seem ungrateful. Appreciate your input.

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XD all gravy the internet is tone deaf. I learned more reading this thread too so I’m happy you made it.

I forgot italics too

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I can provide data down to 10 ppm from LCMS (from a 3rd party lab). Already did so for CBD isolates.

In a couple month, I will try to get this LQ lower once my own LC MS is set up.


I haven’t tested at this levels, but I believe this is not achievable with GC. There maybe always some trace isomerization of CBD to d9 in the hot injector.


We typically perform 0.001% (10 PPM) on our HPLC’s. With our LC/MS, we could perform a 0.00001% LOD but it basically requires that machine to be calibrated for it (dedicated to that one task essentially).

I’m glad someone asked this so I could find out what we are capable of ourselves.

I mean," two zeroes oughta be enough for anybody lol". I bet in 10 years that quote ages like the Bill Gates 640K memory joke.


Yes, we use the LCMS for very low concentration detection.

The GCMS doesn’t do well below 0.1%.


Any chance you guys will make some consumer facing info about the different analytical methods offered and their advantages/weaknesses?