Hawaii is an interesting state to review for cannabis testing data in that it has only one lab since late 2022/early 2023 so there is currently no Lab Shopping dynamics.
Me neither Goeff, there was an enormous building by me that was growing pot ( Michigan) , drove by yesterday and a for sale sign on the building, I wonder why ? 🧐
This is illuminates a significant health consideration for all those who use marijuana as well the various other weeds which are sold for smoking purposes.
I just wish growers would develop some weed that wasn’t “loud!” I wish it didn’t make me reek of marijuana. I bet everyone in the neighborhood knows when I’m smoking! I’d like to be discreet.
This article fails to make the opposite point about how enrichment leads to an abundance of false negatives due to enrichment bias. MCR labs does not use selective media in the MG methods they utilize. The data used in this article fails to take into account a number of issues related to laboratories and state regulatory changes.
If you wet 1g of cannabis in 10ml of fluid, unless you put that entire 10mls into PCR, you cannot claim 1CFU/g sensitivity.
Usually 1ml of 10ml (1/10th) is lysed.
200ul of that 1ml is DNA prepped (1/5th).
1/5th of this Prep is put into PCR.
Total Subsampling is 1/250.
If 1/250th of the 1g makes it into qPCR... you need to at least replicate the sample 250 fold to sample 1CFU/g. If you fail to do this, you are guaranteed false negatives from sampling theory alone. Some media and growth times may not grow Aspergillus 250 fold in the allotted time but we have shown the media and growth time do accomplish this with niger, terreus, flavus and fumigatus. MCR doesn't test for Aspergillus in Mass? Maybe one of their labs in another state is playing with this? Aspergillus doubles every 2-3 hours. 24 hour growth = 12 doublings or 2^12 or 1CFU/g turning into 4,096. For 3 hour doubling times this is 2^8 or 256. This equates to 1-16 CFUs being placed into PCR with 1/250 subsampling.
Kevin, there is an abundance of evidence that enrichment free methods perform in a similar fashion as methods that use enrichment. You are making theoretical claims that do not take into account actual results to trash a company because you are a direct competitor. How many companies have had to take legal action against MG for making false claims about your technology and others?
Alan, You are making claims that cannot be substantiated with basic math.
I encourage you to study Poisson and sampling theory. If you have an abundance of evidence please post it. I have posted hard data from FOIAs from the state of Hawaii who has responded to us confirming this is a concern. Please take legal action. I look forward to that discovery process.
I forwarded your comment to MCR. They replied that they don't test for Aspergillus in Mass and their data isn't in play in this article. Hawaii is being compared to NV and MI Aspergillus detection rates in this article.
As such, I would refrain from giving legal advice regarding accuracy or clarity when you throw other labs into the mix so recklessly.
Thank you for this valid critique. We have contacted the Hawaiian regulators who have confirmed the platform claims to enrich but are concerned over the general detection rates presented.
This is a tactic we have seen this company perform in the past. They claim they don't need enrichment and when regulators demand it, they claim a spin step of theirs acts as an enrichment. This spin step does pellet cells and removes some Dead DNA but does not compensate for the subsampling. Unless a full gram is getting into the qPCR assay, a growth step is required to compensate for subsampling with PCR. If you have information that confirms there is in fact a growth step it would be helpful to compare notes on the length/temp of growth, the use of antibiotics, the type of media etc.. If these are similar to the methods being used in other states, then this implicates the primer design or detection methods.
Not a "pot" ingester in any form, but I found this article full of great points. Thanks.
Me neither Goeff, there was an enormous building by me that was growing pot ( Michigan) , drove by yesterday and a for sale sign on the building, I wonder why ? 🧐
This is illuminates a significant health consideration for all those who use marijuana as well the various other weeds which are sold for smoking purposes.
I just wish growers would develop some weed that wasn’t “loud!” I wish it didn’t make me reek of marijuana. I bet everyone in the neighborhood knows when I’m smoking! I’d like to be discreet.
This article fails to make the opposite point about how enrichment leads to an abundance of false negatives due to enrichment bias. MCR labs does not use selective media in the MG methods they utilize. The data used in this article fails to take into account a number of issues related to laboratories and state regulatory changes.
I think we are talking past each other.
If you wet 1g of cannabis in 10ml of fluid, unless you put that entire 10mls into PCR, you cannot claim 1CFU/g sensitivity.
Usually 1ml of 10ml (1/10th) is lysed.
200ul of that 1ml is DNA prepped (1/5th).
1/5th of this Prep is put into PCR.
Total Subsampling is 1/250.
If 1/250th of the 1g makes it into qPCR... you need to at least replicate the sample 250 fold to sample 1CFU/g. If you fail to do this, you are guaranteed false negatives from sampling theory alone. Some media and growth times may not grow Aspergillus 250 fold in the allotted time but we have shown the media and growth time do accomplish this with niger, terreus, flavus and fumigatus. MCR doesn't test for Aspergillus in Mass? Maybe one of their labs in another state is playing with this? Aspergillus doubles every 2-3 hours. 24 hour growth = 12 doublings or 2^12 or 1CFU/g turning into 4,096. For 3 hour doubling times this is 2^8 or 256. This equates to 1-16 CFUs being placed into PCR with 1/250 subsampling.
Kevin, there is an abundance of evidence that enrichment free methods perform in a similar fashion as methods that use enrichment. You are making theoretical claims that do not take into account actual results to trash a company because you are a direct competitor. How many companies have had to take legal action against MG for making false claims about your technology and others?
Alan, You are making claims that cannot be substantiated with basic math.
I encourage you to study Poisson and sampling theory. If you have an abundance of evidence please post it. I have posted hard data from FOIAs from the state of Hawaii who has responded to us confirming this is a concern. Please take legal action. I look forward to that discovery process.
I forwarded your comment to MCR. They replied that they don't test for Aspergillus in Mass and their data isn't in play in this article. Hawaii is being compared to NV and MI Aspergillus detection rates in this article.
As such, I would refrain from giving legal advice regarding accuracy or clarity when you throw other labs into the mix so recklessly.
The author should have reached out the the Hawaii lab for confirmation of enrichment/no enrichment instead of speculating.
Thank you for this valid critique. We have contacted the Hawaiian regulators who have confirmed the platform claims to enrich but are concerned over the general detection rates presented.
This is a tactic we have seen this company perform in the past. They claim they don't need enrichment and when regulators demand it, they claim a spin step of theirs acts as an enrichment. This spin step does pellet cells and removes some Dead DNA but does not compensate for the subsampling. Unless a full gram is getting into the qPCR assay, a growth step is required to compensate for subsampling with PCR. If you have information that confirms there is in fact a growth step it would be helpful to compare notes on the length/temp of growth, the use of antibiotics, the type of media etc.. If these are similar to the methods being used in other states, then this implicates the primer design or detection methods.
Aspergillus is nasty. Seeing a fungal ball on chest X-ray would always freak me out.
Sounds like some compendial standards maybe useful, lol. I understand the USP is looking at this and hope you had a chance to comment.