painkills2
New Member
I have studied about 25 different test results from four different dispensaries, and if one thing stands out, it is the difference in THC percentages between actual weight and dry weight.
I have corresponded with Jeremy Applen from Page Analytical, and in discussing this issue, he said:
"Because THC content is reported as a percentage of weight by weight (% w/w) the moisture content will definitely affect the value reported. If the moisture content of the product is high, this will cause the reported percentage of THC value to decrease; which is why when you look at results which include the THC % reported both as % dry weight and % actual weight, the actual weight is lower.
When Page Analytical began operations in 2011, there was a lot of dialogue between myself and my first customers as to whether or not the samples should be dried prior to potency analysis. Some labs dry the samples and others don't.
In order to stay in business, I have since had to allow LNPP's to choose which tests they would like, and not all choose to test for moisture or microbiological contaminants."
(Certain punctuation added by me, for easier reading.)
For the 25 test results I have studied, only a few included THC percentages for dry weight and actual weight. The difference between the two is usually around 2 percentage points. And in my opinion, the THC percentage for actual weight is more in line with the strength of a product.
For instance, in March of this year, New Mexicann tested its Medicine Woman strain twice -- the first results included moisture content (9.91% moisture, 12.053% potential THC, actual weight); the second test did not (24.677% potential THC, dry weight).
In New Mexicann's newsletters from March 15th and 19th, Medicine Woman is listed at 15.7% THC, .8% CBDs (don't know where those figures are from); and for March 22nd, the same strain is listed at 25% THC, 0.1% CBD/CBG. But if you look at the latest test results, you can see that New Mexicann rounded the THC potential from 24.677 to 25 (dry weight), and choose to only report CBD/CBGs at 0.1%, when it's actually 0.00% CBDs, 0.184% CBNs, 0.716% CBGs, and CBCs at 1.05%.
It sounds like they are talking about two completely different strains here, and this dispensary's choice in reporting THC/CBD percentages appears to be one of the causes.
So, if you want to use THC percentages as a gauge of potential strength, you will have to ask whether the number indicates dry or actual weight. Since most dispensaries are not choosing to test for moisture content, for THC percentages that are available, patients will need to decrease those reported by about 2% here in New Mexico.
Along with this difference found in reported THC percentages, it appears one must also know if the sample was dried and cured before being tested. Since there doesn't appear to be an indicator within the test results of what type of sample is being tested, I don't know how patients are supposed to locate this information. And at this time, I don't know how much this affects tested THC potential, or how to adjust reported figures to take this into account.
I have corresponded with Jeremy Applen from Page Analytical, and in discussing this issue, he said:
"Because THC content is reported as a percentage of weight by weight (% w/w) the moisture content will definitely affect the value reported. If the moisture content of the product is high, this will cause the reported percentage of THC value to decrease; which is why when you look at results which include the THC % reported both as % dry weight and % actual weight, the actual weight is lower.
When Page Analytical began operations in 2011, there was a lot of dialogue between myself and my first customers as to whether or not the samples should be dried prior to potency analysis. Some labs dry the samples and others don't.
In order to stay in business, I have since had to allow LNPP's to choose which tests they would like, and not all choose to test for moisture or microbiological contaminants."
(Certain punctuation added by me, for easier reading.)
For the 25 test results I have studied, only a few included THC percentages for dry weight and actual weight. The difference between the two is usually around 2 percentage points. And in my opinion, the THC percentage for actual weight is more in line with the strength of a product.
For instance, in March of this year, New Mexicann tested its Medicine Woman strain twice -- the first results included moisture content (9.91% moisture, 12.053% potential THC, actual weight); the second test did not (24.677% potential THC, dry weight).
In New Mexicann's newsletters from March 15th and 19th, Medicine Woman is listed at 15.7% THC, .8% CBDs (don't know where those figures are from); and for March 22nd, the same strain is listed at 25% THC, 0.1% CBD/CBG. But if you look at the latest test results, you can see that New Mexicann rounded the THC potential from 24.677 to 25 (dry weight), and choose to only report CBD/CBGs at 0.1%, when it's actually 0.00% CBDs, 0.184% CBNs, 0.716% CBGs, and CBCs at 1.05%.
It sounds like they are talking about two completely different strains here, and this dispensary's choice in reporting THC/CBD percentages appears to be one of the causes.
So, if you want to use THC percentages as a gauge of potential strength, you will have to ask whether the number indicates dry or actual weight. Since most dispensaries are not choosing to test for moisture content, for THC percentages that are available, patients will need to decrease those reported by about 2% here in New Mexico.
Along with this difference found in reported THC percentages, it appears one must also know if the sample was dried and cured before being tested. Since there doesn't appear to be an indicator within the test results of what type of sample is being tested, I don't know how patients are supposed to locate this information. And at this time, I don't know how much this affects tested THC potential, or how to adjust reported figures to take this into account.