“This distinction matters because culture-based and PCR-based methods can produce materially different results for the same product.”
On Tuesday, the Massachusetts Cannabis Control Commission held a public hearing about testing regulations and protocols. This is an infinitely complex topic with innumerable tangents which we have covered for several years.
While it’s difficult to summarize that coverage, one seemingly appropriate simplification is that regulators basically turned a blind eye to issues such as lab fraud for most of the first decade of adult-use cannabis, and are now apparently paying attention, attempting to mend a massive problem.
The hearing featured many of the same voices that we have heard for years saying the same things. On the hunch that commissioners are finally listening, we are reprinting some of Tuesday’s testimonies over the next two weeks. The following is from Dr. Christopher Hudalla, the president of ProVerde Labs in Milford. -Chris Faraone, TJM Editor
In regard to Laboratory Testing
Good morning, Chair Harding, members of the Commission, and Executive Director Ahern.
My name is Dr. Christopher Hudalla. I am the founder and Chief Scientific Officer of ProVerde Laboratories. I am here to offer comments regarding microbial testing for cannabis.
Massachusetts General Laws, Chapter 94G, Section 15(a)(1), directs the Commission to establish requirements for independent testing laboratories, including protocols for cannabis sampling, testing, and analysis. The statute further directs that these regulations are to be based on standards issued by the United States Pharmacopeia, or USP.
Implementing applicable USP guidance would not only fulfill that statutory direction, but promote greater consistency among laboratories and fairer outcomes for Massachusetts licensees.
First, we recommend the Commission ensure that microbial enumeration methods used are consistent with USP guidance. For total-count microbial testing, including total yeast and mold, the relevant standard is USP General Chapter <61>, Microbiological Examination of Nonsterile Products. That guidance relies on culture- or plate-based methods, which measure viable microbial growth and report results as colony-forming units, or CFU.
PCR plays an important role in targeted, species-specific identification, such as for E. coli or Salmonella. However, PCR does not measure viable microbial growth in the same manner as culture-based enumeration methods.
This distinction matters because culture-based and PCR-based methods can produce materially different results for the same product. Allowing non-comparable methods has contributed to inconsistent outcomes among laboratories, uncertainty for licensees, and reduced confidence that microbial limits are applied uniformly. This disparity in methodologies is also a significant factor in the laboratory-shopping concerns that have taken hold here in Massachusetts.
For total microbial enumeration, PCR should not be accepted as an alternative to USP culture-based methods unless the Commission has reviewed and approved validation data demonstrating equivalency for cannabis as a matrix.
Second, we recommend the Commission review its interpretation of microbial action limits. The Commission’s current interpretation is twice as stringent as the relevant USP guidance. For total yeast and mold in flower, for example, Massachusetts currently enforces a limit of 10,000 CFU/g, while the USP-based recommended limit is 20,000 CFU/g.
Based on a review of a 2025 METRC dataset, approximately 13% of microbial failures under the current enforced limit would have passed under a 20,000 CFU/g USP-recommended limit. Considering batch size and estimated market value, that difference represents approximately $13 million in failed cannabis flower under the more stringent interpretation.
Each microbial failure requires retesting, remediation, and/or repurposing of that batch of cannabis flower. These steps impose significant cost, delay, and operational burden on licensees, in an already challenging environment. Applying the USP-based limits will prevent a meaningful share of these unnecessary failures, along with the associated delays and expense.
As the Commission reviews its testing regulations and protocols, I respectfully urge it to implement and enforce the USP guidance identified in Chapter 94G. Doing so would support scientifically sound, consistent testing standards while continuing to protect Massachusetts consumers.
Thank you for the opportunity to share my perspective.
