Before cannabis legalization in California, most of us consumed cannabis from the black market. We didn’t have a choice. Your first experience was probably some version of this: You’re with friends at a party, someone brings a joint, lights up, and you happily join in. 

Back then no one knew the cannabis content, or even what strain of cannabis you were smoking. Today, the rapidly expanding world of cannabis legalization has changed the landscape for consumers and products. 

To date, 33 states plus the District of Columbia, Guam, Puerto Rico, and US Virgin Islands allow for the use of medical marijuana, and adult use of cannabis is approved in 14 states and territories. (If you’re not exactly sure where your state falls in its legalization and guidelines, NORML’s interactive map is an easy way to view the landscape of legalization in the U.S.)

Now, instead of smoking whatever is brought to the party, you can choose exactly what you consume, decide where you purchase your cannabis, have flexibility and options for how you choose to consume your cannabis, and you have the comfort of knowing exactly what is in the product you consume.

In the state of California, you have a trustworthy way in which you can verify your product is safe and tested; The Certificate of Analysis (COA) on cannabis products. 

When it comes to purchasing cannabis, the second-most important consideration after understanding your state’s laws is choosing where to buy your medical marijuana or cannabis.

You want to choose a dispensary or delivery service that readily provides a Certificate of Analysis (COA) for each product sold.

Here’s what a COA is, and the information you need to know to understand how to read the COA for the product you want to purchase. 

What is a Certificate of Analysis (COA) for Cannabis Products?

In California, the state regulatory agency for all cannabis products is the Bureau of Cannabis Control (BCC). The BCC requires all cannabis products (cannabis flower, cannabis extracts, cannabis edibles, and other cannabis-derived products) to pass a multi-panel lab test and receive a CoA (Certificate of Analysis) from a state-licensed testing lab before the product can be sold to the consumer. The BCC oversees all state-licensed labs. 

The Certificate of Analysis (COA) is the lab report the state-licensed testing lab produces for the chemical make-up (e.g., contents) of the cannabis product based upon the BBC’s mandates

As of December 31, 2018, COA tests include the following for all products (unless otherwise noted): 

Cannabinoid content

This is also known as the potency of the product. The product is tested for the cannabinoids in the product; THC, THCA, CBD, CBDA, CBG; and CBN, as well as the potency. The tests for all products, including; cannabis flower, cannabis edibles, and other cannabis products must demonstrate potency levels within 10 percent of the stated label claim.

For flower products, the dosage is typically presented in a percent by weight. For non-flower products, such as edibles or topicals, dosage information is typically presented in mg/g or mg/ml. Patients may then use this information to determine how much is in a dose that they are taking.

Moisture content (inhalable cannabis flower only)

This is a measurement of the amount of water in a product and is determined by drying the sample. 

Category I & II residual solvents and processing chemicals (inhalable cannabis products & other cannabis products only) 

In concentrated forms of cannabis products, the state mandates tolerance levels for 6 residual solvents in Phase 1 tests and Phase II adds 14 more solvents to the list. 

Category I residual pesticides (Inhalable cannabis products & other cannabis products only) & Category II residual Pesticides 

Pesticides are used in most agriculture – even organically grown products use all-natural pesticides. The labs test for un-natural pesticides. Sixty-six of them. 

Microbial impurities: A. fumigatus, A. flavus, A. niger, A. terrus Microbial impurities: Escherichia coli and Salmonella spp. (inhalable cannabis flower and inhalable cannabis products only)

These are pass-fail tests. If the product exhibits the pathogen, it fails. Otherwise, it gets the green light.

Homogeneity testing of cannabis edibles (other cannabis products only)

This refers to ensuring that the total amount of active cannabinoids are evenly spread throughout the product. 

Foreign Materials

This refers to testing for undesirable foreign materials including but not limited to mold, hair, insects, metal, or plastic which can occur if improper handling during the cultivation process introduced any undesirable foreign materials.

Water Activity Testing of Solid or Semi-Solid Edibles (inhalable cannabis flower & other cannabis products only)

This is a measurement of the amount of free water in a product. This is traditionally a test performed on food products to determine its potential for microbial growth but can be performed on other product types as well such as flowers and concentrates.

Terpenoid content

Terpenes impart flavors and scents to cannabis. Terpene content is not mandatory by the state, but if a product label says the product has a terpene content, the state tests the product to ensure the terpenes being advertised are in the product as advertised. 


These byproducts of fungi are toxic and common on cannabis plants. The most common are subjected to testing: Aflatoxins B1, B2, G1 and G2; and Ochratoxin A. 

These are not pass-fail tests, rather when amounts above certain state-mandated tolerance levels will fail.

Heavy metals

Cannabis plants innately remove heavy metals from their soil. Therefore, the four primary heavy metals: arsenic, cadmium, lead, and mercury are tested for by the state-licensed labs.

The effects of consuming some of these chemicals, especially in the immunocompromised, could be significant.

If a cannabis product or flower fails to pass the required testing and cannot be remedied, then, according to State Regulations, the entire batch must be destroyed. The product cannot be sold to the public.

You can think of the COA as your guarantee that the cannabis product you purchase and consume has passed the state of California’s regulations for a chemically qualified product to consume. 

Now that you know what a COA is, and its purpose, let’s look at what a report looks like and other important things to look for in a report. 

Here’s what to look for on a Certificate of Analysis (COA) for Cannabis Products

See this pineapple express lab report for reference.

Lab report formats vary, however, they should all contain the following information:

The name, address, contact information, and the license # (where applicable) of the testing facility

The name of the product and any other identifiers printed on the label

What is printed on the report should match the label with regard to the product name, dosage, lot number, batch number, and any other identifiers listed.

Sample identification number

This number is used by the laboratory to track the sample. This may include any state-required tracking information, a unique identifier developed by the laboratory, or both.

The date the product was submitted for testing and the date testing was completed

This is important to know to ensure that newly cultivated and manufactured products are being tested and that testing is done promptly upon receipt of the sample. 


Some laboratories place any accreditations and certifications they have received here. Accreditations and certifications show that the laboratory has undergone a review of its quality and operating systems by third-party reviewers to ensure compliance with their respective standards.

Signature Marks

All tests should be reviewed by the laboratory before release. The test report should be reviewed and approved by the Laboratory Director and the Quality Manager.

Testing Summary

This summary table shows all the tests that the sample was subjected to and the outcomes of the tests. This section is not required on a COA but is nice to have so that consumers know immediately what standards the product has been tested to and what their outcome was without having to read the entire report.

You will see the LOD and LOQ listed: 

LOD is the Limit of Detection, which is the smallest amount that the instrument can accurately identify. 

LOQ is the Limit of Quantification, which is the smallest amount that the instrument can accurately quantify.

After the summary, the report will show you a detailed breakdown of the tests listed above:

  • Cannabinoid Content
  • Terpenoid content
  • Moisture content 
  • Category I & II residual solvents and processing chemicals
  • Category I & II residual solvents and processing chemicals 
  • Category I II residual Pesticides 
    • Microbial impurities: A. fumigatus, A. flavus, A. niger, A. terrus  
  • Microbial impurities: Escherichia coli and Salmonella spp.
  • Homogeneity testing of cannabis edibles
  • Water Activity Testing of Solid or Semi-Solid Edibles
    • Foreign Matter 
  • Microbials
  • Mycotoxins
  • Heavy Metals

Reputable manufacturers will consistently test, and easily make available to you, their product’s current certificate of analysis (COA).

You want to buy or consume cannabis products that provide you with a current COA. Lab reports empower you with the opportunity to know exactly what is in the plant, from quality to potency.

Do not purchase a cannabis product if you have not been provided a COA.