California Cannabis Testing

As of July 1st, 2018, California will require mandatory cannabis testing on all inhalable and edible products before they can be sold to the public. Growers are required to submit samples for cannabis testing that contain .35% of the total weight of the corresponding batch.

California’s cannabis testing requires a lab to perform nine different analyses of samples. These tests are listed below, along with the action levels that determine a pass or fail, where applicable.

Moisture Content and Water Activity For Cannabis Testing

For all batches, moisture content will be reported separately as a percentage.
Water activity levels must be below .65 Aw for all dried flower and prerolls.
Water activity levels must be below .85 Aw for all edibles.

Microbial Impurities For California Cannabis Testing

The following must be undetected in 1 gram of both inhalable cannabis and edibles:
Escherichia coli
Additionally, for inhalable cannabis, the following must also be undetected in 1 gram:
Pathogenic Aspergillus species:
A. fumigates
A. flavus
A. niger
A. terreus

Mycotoxin Cannabis Testing

Total of Aflatoxin B1, B2, G1, and G2 must not exceed 20 μg/kg
Ochratoxin A must not exceed 20 μg/kg

Foreign Material

The laboratory must, at a minimum:
Examine both the exterior and interior of the dried flower sample
Examine the exterior of the cannabis product sample

The sample shall be deemed to have passed the foreign material testing if the presence of foreign material does not exceed:
¼ of the total sample area covered by sand, soil, cinders, or dirt
¼ of the total sample area covered by mold
1 insect fragment, 1 hair, or 1 count mammalian excreta per 3.0 grams
¼ of the total sample area covered by an imbedded foreign material

Heavy Metals Cannabis Testing

Inhalable cannabis goods must be below these thresholds to pass:
Cadmium – .2 µg/g
Lead – .5 µg/g
Arsenic – .2 µg/g
Mercury – .1 µg/g
Other cannabis goods must be below these thresholds to pass:
Cadmium – .5 µg/g
Lead – .5 µg/g
Arsenic – 1.5 µg/g
Mercury – 3.0 µg/g


California cannabis testing also includes Cannabinoid and Terpenoid tests, to ensure the product conforms to the labeled content for each Cannabinoid or Terpenoid. It also includes tests on Residual Pesticides, Processing Chemicals and Residual Solvents. For a complete list of all pesticides, chemicals, and solvents with their respective action levels, please see our article on California Cannabis Pesticide Testing

What happens if I fail?

Check out our Cannabis Remediation page to see what options you have after receiving a failing Certificate of Analysis from a cannabis testing lab.

How to Work With Us

Willow can work with you by providing product cleaning services at your location or by selling and servicing your own WillowPure machine.

We’ll bring our technology and expertise to you!

Start-to-finish decontamination service:

• WillowPure technology delivered to your facility
• Access to best practices and recommendations
• Fast and efficient cycle time
• On-site experts to setup, operate, clean and repackage your product

Have your product be safe and sellable by making WillowPure part of your standard process. Willow will install your machine, train your staff and share best practices.

Not in Colorado? We provide out-of-state trials. We also make financing plans available.