Certificates of Analysis (COA)

What is the COA?

When choosing and evaluating any cannabis derived (hemp or “marijuana”) product, experts will advise you to check the COA.  What is a COA?  What kind of information does it provide?  How do you find one for your product?

To answer these questions, let’s start with the basics.  A COA is a ‘certificate of analysis’ for a given product.  This is the report generated by the testing laboratory that is responsible for analyzing products as part of a quality control effort.  You can find COAs reported by either an independent (3rd party) lab or by the product company’s internal testing protocol (referred to as 1st party).   An independent, unbiased source performing the analysis and generating the report is ideal.

Why is the COA necessary?

As the cannabis industry continues to grow, consumers deserve and are demanding the highest quality possible.  The best method of ensuring that the cannabis products available meet these demands, is to scientifically analyze them and compare the results to known standards and/or with the manufacturer’s labeled claims.

An interesting article written in the Journal of the American Medical Association, published in 2015, illustrated the discrepancy between product label claims and actual content.  This further highlighted the need for quality control and testing.

Click the link below to read:

Cannabinoid Dose and Label Accuracy in Edible Medical Cannabis Products.  https://jamanetwork.com/journals/jama/fullarticle/2338239

Long gone are the days when cannabis plants and the dried flower could be differentiated by the look and smell of the raw material.  Today’s crops are largely hybridized and the choices of finished products available to the consumer come in all forms and are heavily packaged.

In addition, product packaging can have descriptions and wording that is often confusing to the consumer and cannabinoid content may not even be clearly listed on the label.  Instead, phrases such as; “full spectrum,” “broad spectrum,” “phytocannabinoid rich or PCR,” and “isolate” are often encountered.  Confusion about these terms can be the source of much debate.  Furthermore, they are often used as a marketing tool rather than as a scientific description.

Products that contain the full complement of active components taken from the plant have the greatest synergy.  This synergy is also known as the “entourage effect” and describes the increased benefits from the combination of all these active plant derived compounds.  These compounds include not only the cannabinoids, but also terpenes, flavonoids, and fatty acids.  In contrast, products that have only a single cannabinoid are referred to as isolates (a single active ingredient isolated from the plant).  The general acceptance in the industry is that “full spectrum” extract products have all the available components that are present in the plant.  “Broad spectrum” typically means the full spectrum extract with the THC component removed and “Isolate” means a single, purified ingredient.  Please note however, that these terms have not been specifically defined by the industry and some variation does exist.  Regardless, the COA can be used to verify any of these claims and confirm the active ingredients in the product.

Therefore, independent testing of products is necessary to remove the guesswork, clear up any confusion and provide information on:

Safety: ensuring that the product is free from harmful contaminants and microbes.

Efficacy: ensuring that the product contains the active ingredients that the consumer is seeking.

Consistency: ensuring that sequential batches of products have consistent ingredients for reliable, repeatable results.

How is the report created?

COAs can contain different types of testing information, based on many factors including, but not limited to:

  • Is the product “marijuana” or hemp derived?
  • In what state is it produced and are there any specific requirements for lab testing?
  • What type of product is being tested? (plant, liquid, edible, etc.)
  • Which lab is doing the testing and what methods are they using?
  • Is there any quality control regulating the laboratory itself? Is it ISO certified?
  • Is the testing requested by the company or a regulatory authority?

Data can be presented in different forms: tables, graphs, pictorials, pie graphs, scatterplots, etc. depending on the reporting source.

Testing procedures involve separation of the product into its individual components and the measuring of each.  There are different techniques used for this, depending on the laboratory.  The specifics of which will not be detailed in this article, but there are plenty of resources for those who would like more information.  Analytical labs detail their testing protocols on their individual websites.  Alternatively, here is a link to a great synopsis and an interesting article written by Rod Kight on his blog:

HEMP TESTING 101: ANALYTICAL TESTING PROTOCOLS EXPLAINED AND EVALUATED.  https://cannabusiness.law/hemp-testing-101-analytical-testing-protocols-explained-and-evaluated/

What information should be on the COA?

Testing requirements may vary, depending on state regulations.  In general, for accurate quality control, you need to be able to find the testing laboratory’s information (name, location, license #), as well as the distributor’s and/or manufacturer’s information (name, location, license #), the sample type and the batch information.  Also listed should be the dates of collection and testing dates as well as the method of analysis.  They are usually signed by the scientist in charge.  Some reports have QR codes for the consumer to scan to access data and confirm.  A reputable company will test each batch of product and not just occasional or periodic random testing.  There should be corresponding batch information on the product label for identification and comparison.

How to read the report and interpret the information:

  1.  The Cannabinoid profile or “Potency”: (amounts of the different cannabinoids in your product) These values are listed as both percentages AND concentration in milligrams per milliliter (mg/ml) or milligrams per gram (mg/g) depending on the type of product. Milligrams (mg) is the unit of measurement for the active ingredient and for how the active ingredients are measured for dosing. There should also be a “total cannabinoids by weight” of the product sample. In products that have different forms of the various cannabinoids (for example, both CBD and CBDA), there will also be a reported total, which is the amount of the activated cannabinoid that would be if all the carboxylic acid has been removed through decarboxylation.  e. CBD Total = (CBDA * 0.877 + CBD)

From an accuracy perspective, this is the area which can often vary when compared to the product label.  Manufacturers do not necessarily change the product packaging for every batch of product made.  In general, expect the package label to have the expected values in mg, but look for the batch testing sticker or individual COA for a true measure of the ingredients present.  This is also why it is necessary to test every batch of product, since there can be variations present originating at different points in the cultivation and manufacturing process.  For example, in California, all cannabis potency levels must be within 10% of the stated claim.

Also note that this information is crucial to determine actual levels of cannabinoids present in a product that may not have them specifically listed on the label.  For example, if a product label states that it contains a certain number of mg of “hemp extract”, the COA is necessary to determine which (if any) cannabinoids are present and the amounts of each.

  1.  Microbiological Screen: (If there is any bacteria, fungus, or mold contamination) Although these organisms are ubiquitous in nature, accidental ingestion of cannabis contaminated with disease causing pathogens such as e. coli or salmonella can cause health problems. Testing for the presence of harmful microbiological organisms and aflatoxins ensures that the product is safe for consumption. On the COA, this information is generally listed as CFUs (colony forming units).  The end result is generally listed as pass or fail, based on limits set by the lab and/or the state.  Interestingly, most microbiologic contamination results from improper handling during the manufacturing process.                                                                                                                    
  2. Pesticide and Solvent Residue Screen: (If there are any chemical, heavy metal or solvent residues) This information is generally measured as PPM (parts per million) for each individual element tested and given a pass/fail designation. It’s important to test for harmful residues, such as pesticides and heavy metals (arsenic, cadmium, lead and mercury) because of the cannabis plant’s ability as a ‘bioaccumulator’ (a plant that can absorb toxins present in the soil or environment). Chemical solvents used in some extraction processes can leave behind residues of butane, hexane, acetone, methanol, glycols, etc. that you do not want in the finished product.                                                                                                                                            
  3.  Terpene profile: While not always present on standard COAs, expect to see more information on cannabis terpenes as the industry moves forward. The cannabis plant is rich in terpenes, and their presence in the final product can have a marked impact on the overall effect to the user. Those COAs that include terpene profiles can list the information in a variety of ways (graphs, tables, pictograms, etc.).   The amounts present can be listed as mg or percentage or both.  In addition, some labs list only the most common or dominant terpenes present, while others will list them all with their corresponding results.  Product manufacturers are increasingly realizing the importance of these compounds, especially as it relates to the “entourage effect.”

Other types of information that can be found on the COA:

Moisture will be reported in testing of raw material/flower.

Other terms to look for: NA (not applicable), NR (not reported), ND (not detected), BLQ (below level of quantification), TR (trace), LOD (limit of detection), LOQ (limit of quantification) and TNTC (too numerous to count).

It is also possible to consult with the testing lab for further clarification, if needed.

How to obtain the COA?

Many consumers do not realize that this information may be available to them.  When investigating products and reading labels, there is a very limited amount of information that can be printed on the packaging.  In order to get further information, there are several resources available.  If the consumer utilizes traditional retail outlets, ask the store manager if they have more product information on file.  Many products have phone numbers or website addresses listed on the label for customer service questions.  In addition, navigating the product websites can often lead to the published COAs for each product.  When in doubt, reach out to the company and specifically request the report.  If a manufacturer or product company is not forthcoming with this information, this may be a ‘red flag’ to the consumer.  Reputable companies who strive to provide quality products should be transparent and readily provide information.  Seek out companies who do.

Finally, it is important to note several points:

-There may be multiple reports for different stages of the manufacturing process for a particular product.  However, for the information to be as accurate and relevant as possible, it is best to consult the COA for the final, finished product that the consumer is going to use.  This is to avoid the scenario in which, for example the COA for the raw material may test negative for microbes, but the finished product could have contamination after that point.

-Just as the laws regarding cannabis products vary by state, so do the requirements for testing.  There are some states with legalized cannabis that do not require any testing.  Regarding hemp-derived products, there is currently no requirement at all for this type of testing of products in the US.  To many in the industry, it is a ‘wild west’ type of situation.  The expectation going forward, is that the FDA will pursue this when creating the regulatory guidelines for hemp containing products.

Click the link below to read about testing regulations by state.  Be aware that the rules are constantly changing, so be sure to confirm current, updated information on individual state’s policies via state sponsored legal websites.


In California, for example, by 2019 the BCC (Bureau of Cannabis Control) will adopt some of the most stringent regulations in the country regarding required testing of cannabis products.  While this may be burdensome to the industry and cost more to bring finished products to the consumer, this attempts to ensure that the products available for consumption are held to the highest standard.

In the end, when deciding on a product to purchase, do your due diligence!  As the industry grows and consumer demands for higher quality rises, so does the need for transparency on the part of the product companies.  It behooves manufacturers to provide reliable, easy to obtain information about their products.  The consumer needs to know how to obtain and interpret the COA in order to make educated decisions when it comes to the best products for their health.



COA and Lab Testing References for further reading:

The Ultimate Guide to California Cannabis Lab Testing Regulations. February 26, 2018.  https://b2b.gocaliva.com/ultimate-guide-to-california-cannabis-lab-testing-regulations/

The Bureau of Cannabis Control California, Laboratory Testing Fact Sheet.  https://www.bcc.ca.gov/about_us/documents/18-286_labtest_factsheet.pdf

CW Analytical, Interpreting Results.  http://www.cwanalytical.com/results/

Hemp Testing 101: Analytical testing protocols explained and evaluated. Dec 2018. Rod Kight https://cannabusiness.law/hemp-testing-101-analytical-testing-protocols-explained-and-evaluated/

Cannabinoid Dose and Label Accuracy in Edible Medical Cannabis Products. Vandry, et al.  https://jamanetwork.com/journals/jama/fullarticle/2338239?alert=article

CBD Lab Reports: Why They Are Important & How to Read Them.   https://intellicbd.com/articles/how-to-read-cbd-lab-reports/