Certificate of Analysis (COA): All the Basics You Ought to Know
GBL Editors
March 25, 2023
Ever wonder what's really in your cannabis products? You might be surprised by what's lurking in there. And — considering that you're putting THC and CBD products on or into your body — you probably don't want to be caught off guard. Enter the certificate of analysis, or COA.
In this post, we'll analyze the COA so that you come away knowing:
What a COA is and how to tell if it's legitimate
What a COA can tell you
Why these certificates are so important
How to read a COA and leverage the info it gives you
Without further ado, let's get into it.
Dr. Joan Irvine and Barbie Sommars answer the question "what is a COA?" on know n' go, a GBL TV original series.
Table of Contents
What is a Certificate of Analysis?
A certificate of analysis is an official document that provides laboratory testing results about the chemical and physical properties of a sample. It's also known as an assay or lab report.
The purpose of a COA is to help verify the safety, quality, and potency of the ingredients in a product. The report will confirm the content, strength, and purity of the tested sample.
The COA will also clue you in to whether or not the product it goes with conforms to the manufacturer's stated processes and standards. And it'll help you determine if what the makers say on/in the packaging, labeling, and inserts is accurate and complete.
Think of the certificate of analysis as your ally in the quest for product truth.
What Information Does a Certificate of Analysis Include?
COAs can be veritable treasure troves of useful details! Depending on what the lab tests for, you can learn a lot about your cannabis product. At the very least, a good certificate of analysis should include basic info like the:
Name of the certifying laboratory
Product being analyzed
Testing date
What's most interesting, though, are the actual results of the analysis. This can include:
Test data and testing details
The components of a product, including cannabinoids and possibly terpenes
Information about ingredients
Indications that the product's been tampered with
Indications that the product contains unauthorized ingredients, adulterants, toxins, or other potentially harmful elements
Any relevant comments
There could also be information about the manufacturing process as well as health and safety measures.
Is This COA Legit?
But, not all documentation that accompanies your cannabis products will be of equal caliber. A trustworthy certificate of analysis is one that:
Is comprehensive yet clear and concise
Done by a reputable and independent, third-party lab that specializes in this sort of testing
Why's a Cannabis COA Important?
A COA is important because it proves that the cannabis in your product meets your expectations. It gives you a way to compare what the product is supposed to be to what it truly is. The certificate of analysis enables you to know, for example, what's really in that CBD tincture you're ingesting.
One important aspect of the COA is that it tells you how much THC, CBD, and other cannabinoids are in your cannabis goods. You absolutely need this info because:
You want to make sure there's actually cannabinoids in there, and make sure it matches what's on the label.
THC may be something you're trying to avoid because you don't want the psychotropic effects, are subject to drug testing, etc.
Dosing is different for pets than humans.
Pro tip: Keep a copy of the COA with your product. If you ever need to prove it's Farm-Bill legal, such as if you're traveling — this could be your only way to do it.
Most cannabis consumers have their favorite products, go-tos that are known to work for them. Certificates of analysis offer a way to track product consistency over time.
This is particularly important if the products or brands that you like are bought by another company or ingredients are sourced from an alternate supplier. Looking at the COA can tell you if something in the product profile has changed. And a product with a different mix of cannabinoids, terpenes, etc. might perform differently for you than its prior version.
How To Read a Certificate of Analysis So It Makes Sense
How can you use a certificate of analysis if you can't decipher what's on it? You can't. That's why it's critical to understand the parts of the report and what each piece of analysis or info means.
Key Terms on a Certificate of Analysis
Let's start with some of the jargon and acronyms you might see on a COA. These are super common:
Limit of Quantification (LoQ). This is the minimum amount of a substance that a test is able to quantify numerically. If an amount is smaller than this, the results will not give a numerical value but will instead indicate that the substance was below this threshold (e.g., It'll show something like "<LoQ" in the results.).
Level of Detection (LoD). This is the smallest concentration that a test can consistently be distinguished from all the other stuff in the sample. Below this concentration, the results will show the substance was below this threshold (e.g., It'll show something like "<LoD" in the results.).
None Detected (ND). This means none of the substance was detected in the sample.
Not Tested (NT). This means that the given substance wasn't analyzed as part of the testing protocol.
Colony-Forming Unit (CFU). Some labs test for microbes in the samples. CFUs are just a standard unit of measurement for the number of microbes.
Reading a COA
Each company's COAs are going to look a little different — layout, colors, etc. But that's no big deal because the "bones" of the report will be the same. They'll all have lab, company, product, and testing details.
For the most part, you only need to identify and evaluate a few pieces of info:
Make sure that the names and addresses of the testing lab and the product maker aren't one and the same. Remember — you're looking for an unbiased analysis from an unaffiliated testing center.
Confirm that the COA you're looking at is indeed for the product and batch you're interested in. The COA should correlate to the item you're viewing (or have purchased). Sometimes the COAs for multiple products (from the same brand) are grouped together.
Verify the CBD and THC levels. Some COAs just say the sample "passed." Others will give you the actual bits of data so you can compare the specification (stated or expected amount of the cannabinoid) versus the detected amount (the result). You want to make sure that the quantities of each cannabinoid align with what's claimed in the product information. (If the amount of claimed vs detected cannabinoids is different, it may be OK. There is an acceptable range of variance.)
Review the terpene and microbiology results. If the COA includes this info — not every company has these things analyzed — look it over. Obviously, you don't want a product that's swimming with salmonella. Beyond this no-brainer data, these details may give you a better idea of the likely smell, taste, and effects of the product.
Taking a gander at the COA is best done before you buy a cannabis product. We recommend that you start including reading COAs as a step in your pre-purchase due diligence. Just add it to the research checklist! This way, you have a better chance of knowing and having confidence in the integrity of the THC or CBD products you end up buying.
Sample Certificates
Theory's great — but looking at real-world examples may be more helpful. Check out some actual COAs for CBD products on the Green Bee Life COA database. You’ll find COAs for every product on the GBL Marketplace there.
Are COAs Legally Required?
Only some states require cannabis companies to test their cannabis products. The rules and requirements vary by state and by type of cannabis (e.g., marijuana- or hemp-derived, THC vs CBD).
The same goes for COAs. Only some states actually mandate that there be a certificate of analysis for each batch of each product. In any case, a producer that's worth its salt will have certificates of analysis for its products anyways — it's good business sense to have one because consumers are getting savvier by the day and are expecting COAs.
Sellers like COAs because they're a competitive advantage. The reports help:
Answer customer questions
Build consumer confidence in the product and brand
Ensure safety and potency
Reduce returns and other issues
COAs Help You be a Smarter, Safer Cannabis Consumer
A certificate of analysis can be used to determine the purity, potency, and quality of cannabis. It will tell you how much of which cannabinoids are in your cannabis product and can also help indicate if there are contaminants.
Learning how to read and interpret a COA takes some practice but is worth the effort. The COA is an incredibly useful tool for having confidence in a product's safety, efficacy, and legality.
FAQs Buzzin’ Through the Hive
What is a certificate of analysis?
A certificate of analysis (aka COA) is a document that states what’s in a product, ingredient, or other substance. It’s sometimes referred to as an assay or lab report.
What is the purpose of a certificate of analysis?
A COA is intended to let you know exactly what’s in your cannabis product. It will tell you which cannabinoids are present and in what amounts. It may also let you know if other substances — like heavy metals or pesticides — are present.
Where to get certificate of analysis?
A good retailer will have a COA for every product. COAs should be made readily available — easy to find and access. Many online retailers link to the COA from their product pages or top level of the website navigation menu. If you’re shopping in person at a store, you may have to ask a clerk for COAs. Some manufactures include a QR code on the packaging.
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About the Author
GBL Editors
Green Bee Life’s editors are a team of cannabis and plant-based wellness enthusiasts dedicated to bringing you accurate and transparent information. We stay on top of the latest cannabis news, trends, and research to provide recommendations rooted in personal experience and careful research. We only endorse trusted brands that meet our rigorous standards for quality and transparency.
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