By Roulette Massey, Laboratory Director, Greenleaf Labs
As Laboratory Director at Greenleaf Labs, one of the most common things I hear from operators is this: “I get my COAs back, but honestly, I’m not always sure what I’m looking at.”
And the truth is that’s more common than most people admit.
Cannabis Certificate of Analysis reports are filled with scientific terminology, numbers, abbreviations, and compliance information that can feel overwhelming if you’re not working inside a laboratory every day. But understanding your results is incredibly important for protecting your business, your products, and your customers.
At Greenleaf Labs, we believe testing should never feel confusing or intimidating. A good lab doesn’t just provide data — it helps clients understand what the data means.
Here’s a practical breakdown to help you better understand how to read and interpret your Certificate of Analysis.
What Is a Certificate of Analysis (COA)?
A Certificate of Analysis, or COA, is the official laboratory report that shows the results of scientific testing performed on a cannabis sample or finished product.
Depending on the sample type and state requirements, your COA may include potency testing, terpene analysis, microbial screening, pesticide testing, heavy metals, residual solvents, water activity, and more.
From my perspective as a lab director, a COA is much more than a compliance document. It’s a snapshot of product quality, consistency, and safety.
Start With the Sample Information
The first section of your COA contains identifying information about the sample submitted for testing.
This usually includes:
• Batch or sample ID
• Product name
• Product type
• Dates received and tested
• Client information
• Testing methods used
I always recommend operators verify this section first before reviewing the results themselves. Something as simple as a batch number discrepancy can create compliance headaches later if it’s missed early.
Understanding Potency Results
Potency results are often the first numbers people focus on.
This section measures cannabinoids such as THC, THCA, CBD, CBDA, CBG, CBN, and other minor cannabinoids.
One of the biggest misconceptions I see involves the difference between THC and Total THC.
Raw flower naturally contains mostly THCA. When heat is applied, THCA converts into THC through a process called decarboxylation. That’s why COAs often list both THC and Total THC.
Understanding that difference matters for product labeling, consistency, and compliance.
Why Terpenes Matter
Terpene profiles provide valuable information beyond aroma and flavor.
Compounds like Myrcene, Limonene, Caryophyllene, Pinene, and Linalool can help cultivators and manufacturers better understand product consistency and post-harvest handling.
From a laboratory standpoint, terpene data can also reveal trends related to cultivation practices, storage conditions, and processing methods.
For brands and dispensaries, terpene profiles can become an important educational and marketing tool as consumers become more informed.
Understanding Pass vs. Fail Sections
One of the most important parts of any COA is the safety and compliance section.
This area determines whether a product passes or fails state-required contaminant screening.
These sections may include:
• Microbial testing
• Heavy metals
• Pesticides
• Residual solvents
• Mycotoxins
As someone who has spent years working inside cannabis laboratories, I can confidently say that safety testing matters just as much as potency. High THC numbers do not matter if a product fails contaminant testing.
Common Lab Terms Explained
COAs often include abbreviations and scientific terminology that can easily confuse operators.
Here are a few common examples:
ND = Not Detected
This means the analyte was not detected above the laboratory’s reporting threshold.
LOQ = Limit of Quantitation
The lowest concentration that can be accurately measured.
ppm = Parts Per Million
Commonly used for contaminants like pesticides and heavy metals.
ppb = Parts Per Billion
Used on Greenleaf Labs COAs for mycotoxins.
CFU/g = Colony Forming Units Per Gram
Typically used in microbial analysis.
Why Understanding Your COA Matters
The cannabis industry continues to mature, and operators are becoming more educated about testing standards and product quality.
Understanding your COA helps you:
• Protect your brand reputation
• Improve product consistency
• Reduce compliance risk
• Better educate customers
• Make informed operational decisions
I truly believe transparency builds trust. Operators should never feel uncomfortable asking questions about their results. A reliable laboratory should be willing to explain the science clearly and stand behind its data.
Final Thoughts
At Greenleaf Labs, our goal is not just to provide testing services — it’s to help clients better understand the information behind the results.
Cannabis testing can seem complicated at first, but the more familiar you become with your COA, the more valuable it becomes as a business tool.
Clear communication, accurate science, and transparency are all part of building a stronger cannabis industry.
And in my experience, informed operators make better decisions for both their businesses and their customers.
