California Lab Testing Requirements

On January 1st of this year, as a result of the passage of Prop 64 (aka the “Adult Use of Marijuana Act”), the sale of recreational cannabis was made legal in the state of California.  Simultaneously, a series of proposed regulations created by the Bureau of Cannabis Control (BCC) nominally went into effect.  Below is a summary of the testing requirements broken down by Phase.
  • Anresco-104

    On January 1st of this year, as a result of the passage of Prop 64 (aka the “Adult Use of Marijuana Act”), the sale of recreational cannabis was made legal in the state of California.  Simultaneously, a series of proposed regulations created by the Bureau of Cannabis Control (BCC) nominally went into effect.  One of the most consequential new regulations was the requirement that all batches of finished product, regardless of whether intended for medicinal or recreational use, be sampled and tested by an accredited third party laboratory to ensure safety and dosing accuracy.  To ease the burden on growers and producers, the testing requirements were to go into affect in phases and producers could bypass Phase I requirements (so long as their products were labeled as not meeting the state’s standards).

    Below is a summary of the testing requirements broken down by Phase:

    Phase I: January 2018
    FlowerConcentrates (inhalable)Edibles/Other
    • Potency
    • Residual Pesticides
    • Microbial Impurities + Aspergillus
    • Moisture
    • Terpenes (if labeled)
    • Potency
    • Residual Pesticides
    • Microbial Impurities + Aspergillus
    • Residual Solvents
    • Moisture
    • Terpenes (if labeled)
    • Potency
    • Residual Pesticides
    • Microbial Impurities
    • Residual Solvents
    • Terpenes (if labeled)
    • Homogeneity (every 6 months)
    Phase II Additions: July 2018
    FlowerConcentrates (inhalable)Edibles/Other
    • Additional Pesticides
    • Additional Pesticides
    • Additional Residual Solvents
    • Additional Pesticides
    • Additional Residual Solvents
    Phase III Additions: January 2019
    FlowerConcentrates (inhalable)Edibles/Other
    • Heavy Metals
    • Mycotoxins
    • Water Activity
    • Foreign Material
    • Heavy Metals
    • Mycotoxins
    • Water Activity
    • Foreign Material
    • Heavy Metals
    • Mycotoxins
    • Water Activity
    • Foreign Material

    Phase I and II

    Potency:

    For all products, the state requires that a homogenized sample of a tested product be within 10% of the stated label claim.  However, for inhalable products, the potency must be reported based on dry weight (adjusting for moisture within the flower or concentrate).  So, for example, if a flower sample is determined to contain 18% cannabinoid and 10% moisture content, the dry weight cannabinoid content would be calculated as 20% (18% / 0.9).

    Pesticides:

    Pesticide residue testing is perhaps the most consequential of the tests, given the prevalence of pesticide use in the industry and their tendency to concentrate in extracts.  For Phase I, the BCC mandated testing of 21 residual pesticides, but interestingly did not include myclobutanil, by far the most common pesticide used in cannabis production and perhaps also one of the more dangerous.  Additionally, no action levels were provided for the pesticides, meaning that each lab could set their own tolerances (which may result in uneven quality of lab results).

    However, for Phase II, the BCC added an additional 45 residual pesticides and provided tolerances for each.  The limits mandated essentially require the use of both an LC-MS/MS (liquid chromatography tandem mass spectrometer) and GC-MS/MS (gas chromatography tandem mass spectrometer), which can be hundreds of time more sensitive for broad multi-residue analyses (MRAs) than the instruments currently used by some cannabis labs.  While this will likely result in greater cost for producers, it will also go a long way towards standardizing the quality of testing labs and cannabis products in general.  For reference, almost all laboratories performing MRAs of foods and pharmaceuticals utilize these instruments.

    Microbiology:

    Unlike the BCC’s initial draft, the updated regulations focus more on specific pathogens rather than broad measures of microbial quality. This was done most likely out of an effort to reduce the number of product failures, as cannabis plants can have high microbial loads, which is not inherently dangerous.  Ironically, this may increase the price of testing, as the prior draft regulations and most cannabis labs previously focused on the AHP monograph and thus did not have the requisite PCR instrument in-house.

    Consumed products must be tested for shiga toxin producing escherichia coli (STEC – a subset of all e. coli) and salmonella.  Inhaled products must additionally be tested for aflatoxins – carcinogenic compounds produced by certain types of molds.  All tests are qualitative – if the pathogen is present, the product fails; if it is not, the product passes.

    Residual Solvents:

    For Phase I, the BCC only requires testing of 6 residual solvents, none of which are commonly used.  Additionally, no action levels are provided, meaning that labs again can set their own standards.  For Phase II an additional 14 residual solvents are added with varying action levels permitted for each.

    Homogeneity:

    The BCC requires that edible companies validate the homogeneity of their products at least once every 6 months.  The average potency of all samples must be within 10% of the reported cannabinoid value and the standard deviation of all samples must be less than 10%.  However, they leave it up to the laboratory to determine their own testing protocols, such as how many subsamples to include in a test.  Anresco has decided to test samples consistent with United States Pharmacopeia (USP) protocols.

    Terpenes:

    Terpenoid profiles are only required for products with labeled claims.  The tolerance for variance is the same as for cannabinoids – plus or minus 10% of the claimed value.

    Phase III

    Heavy Metals:

    Heavy metals testing has been a hot topic in the cannabis testing community.  On one hand, cannabis plants have the propensity to bioaccumulate heavy metals and can even be used for phytoremediation – the process of cleansing soil by growing plants that will accumulate contaminants.  On the other hand, some argue that there is limited data to indicate heavy metals are present in the flowers at levels that could pose a public health concern.  In any event, the BCC requires testing for the four primary heavy metals in phase III: arsenic, cadmium, lead, mercury.

    Moisture and Water Activity:

    Moisture testing is actually mandated in Phase I but it belongs in the same conversation as water activity.  Both are of concern because pathogens require water to grow.  Moisture is perhaps more intuitive to understand, as it’s just the total percentage of water in a product.  It can be determined directly, such as by superheating a sample in a convection oven and measuring the weight loss due to water evaporation, or indirectly, using instruments such as NIR.  The BCC set a tolerance of 13% moisture for inhalable cannabis products.

    Water activity however is the better measure of the microbial growth potential in a given product, because it is only the measurement of free or available water.  It is measured as the ratio of water vapor pressure of the food to the vapor pressure of pure water under the same conditions.  So water inherently has an Aw value of 1.0 and all foods some fraction of that amount.  The BCC set a tolerance of 0.65 Aw, which may be a reasonable value for cannabis itself, but could prove problematic for some edibles, as even the FDA does not regulate foods below 0.85 Aw.

    Mycotoxins:

    Mycotoxins are toxic byproducts produced by fungi, which are omnipresent on cannabis.  The BCC requires testing of the most common and dangerous mycotoxins: Aflatoxins B1, B2, G1, and G2; and Ochratoxin A.  The tolerance for all is set at 20 micrograms/kilogram (i.e. 20ppb), which is the same as the action level set by the FDA for most foods.

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    It is important to note that these regulations are still in draft form.  It is very likely that the BCC will further modify the requirements, especially for later phases, as they receive additional feedback from laboratories and producers.  The commentary above thus should not be considered negative or positive, but merely an evaluation of the testing requirements in their present state.

    Perhaps more important than the precise quality standards and limits that will be mandated, will be the BCC’s ability to enforce them.  Given how new the state is to monitoring private laboratories and at performing cannabis testing itself, it will be difficult to maintain a level playing field initially.  As we’ve seen from other states (Washington, Nevada), such an environment can disproportionately benefit bad actors to the detriment of the industry as a whole.

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    Anresco Laboratories is capable of performing all Phase I, II, and III tests to the standards outlined by the BCC.  Contact us for more information.