By Dr. Daniela Vergara
A Certificate of Analysis (COA) is like a report card for your cannabis product. It tells you what’s in the product and whether it passed safety tests. Every legal cannabis product sold in New York must have a COA, which you can usually find by scanning the QR code on the product label. Understanding a COA helps you stay safe, informed, and get the effects you’re looking for.
New York State requires cannabis products to go through lab testing to help keep people safe. This testing makes sure that the products sold at licensed dispensaries meet safety standards. It also gives buyers important details about what’s in the product.
Lab tests check for:
- THC, CBD, and other cannabinoids
- Germs like bacteria and mold
- Harmful metals (like lead or mercury)
- Pesticides (chemicals used to kill bugs)
- Solvents left over from extraction
- Moisture levels (water activity)
- Dirt, hair, or other unwanted materials
- Other possible contaminants
Although this post will help anyone anywhere read a COA for marijuana-type C. sativa, we are focusing on New York State.
Header Information
This section is usually at the top of the Certificate of Analysis (COA) and helps you verify the product’s identity and history.
Look for these details:
- Lab Name & Address: Shows which certified lab did the testing. Labs must be licensed by the state.
- Organization Name & License Number: This tells you the business that made the cannabis product and their official New York State license number.
- Product Name: The name of the product, such as a specific strain or brand.
- Sample Name: Describes the cannabis product being tested.
- Sample Type: Tells you the final form of the product (like flower, pre-roll, lozenge, edible, etc.).
- Lot Number or Unique Identifier: A special code that allows the state to trace the full history of the product—from where it was grown to where it was sold. This is also used to recall products if there’s a problem.
- Batch/Sample ID: A specific code that identifies the exact sample tested in the lab.
- Collection Date: The day the lab collected the sample from the producer.
- Received Date: The day the lab received the product for testing.
- Reported Date: The day the final results were shared with the producer.
- Report Status: Tells you whether the testing is finished or still in progress.
These details make sure the lab results match the product you’re buying and help track the product for safety and quality control.
Cannabinoid Profile
This part of the COA tells you how much of each cannabinoid is in your product. These cannabinoids, as we discussed in a previous post, are compounds made by the cannabis plant, and may affect how the product works in your body. Some common ones include:
- THC:This is the chemical that causes a “high.”
- CBD:This does not get you high and is often used for calming effects.
- Other Cannabinoids: These may include CBG, CBN, and CBC.
- THCA and CBDA are the “acidic” forms of THC and CBD, again as discussed in a previous post.
- When cannabis is heated (like when smoked or vaped), these acidic forms change into active forms (THC and CBD) through a process called decarboxylation which we’ve mentioned before (link).
In New York State, the results will usually look like this:
- Flower and vapes show cannabinoid levels in percentages (%).
- Edibles show the amount in milligrams (mg) per serving and per package.
Some COAs also include ratios, such as 1:1 THC:CBD, which help you understand the balance between different effects (for example, relaxing vs. energizing).
REMEMBER:
- The Total THC is calculated using this formula:
Total THC = (0.877 × THCA) + THC
Why? Because THCA loses weight when it’s heated, as it releases carbon dioxide (CO₂) and turns into THC. That number, 0.877, is used to adjust for that change and we discussed that in a previous post. - How cannabinoids are tested matters too:
- Gas Chromatography (GC) uses heat, which turns acidic forms (like THCA and CBDA) into their neutral forms. This means GC only shows THC and CBD, not their original acidic forms. So, if you see in your COA only these neutral numbers it means that either the lab that performed the test added the acidic and neutral forms together already or that the lab only uses a gas chromatography equipment which is unlikely. As we mentioned in a previous post, GC is mostly used to test for terpenes which are volatile.
- High-Performance Liquid Chromatography (HPLC) does not use heat, so it can measure both acidic and neutral forms. Because of this, HPLC is the most common method used for cannabis testing, and it gives a more complete picture of what’s in the product.
If your COA only shows the neutral forms like THC or CBD, it could mean one of two things: either the lab has already combined the acidic and neutral forms into one number through the formula from above which is usually labeled as Total THCor Total CBD, or the lab used gas chromatography, a method that only detects the neutral forms. However, most labs use liquid chromatography, which can show both forms, so it’s uncommon for gas chromatography to be used for cannabinoid testing.
Terpene Profile (if available)
Terpenes are compounds that give cannabis its smell and may also affect how it makes you feel. Common terpenes include:
- Myrcene: Earthy or musky smell.
- Limonene: Citrus smell.
- Pinene: Pine scent.
- Linalool: Floral scent.
Not all labs include terpenes, but if they do, it’s a bonus for understanding your product’s aroma and possible effects.
Contaminant Testing
This part is all about safety. Labs check for:
- Pesticides: Chemicals used in farming, should not be present in high amounts.
- Heavy Metals: Things like lead, mercury, or arsenic that can be toxic.
- Microbial Impurities: Bacteria, mold, or yeast that can make you sick.
- Residual Solvents: Used in making extracts, should be below safe limits.
- Foreign Materials: Anything that shouldn’t be there, like hair, plastic, etc.
Each result should be marked:
- “Pass” = safe to use.
- “Fail” = should NOT be sold.
In New York, all legal products MUST pass these tests before being sold.
Pass vs Fail: At the top of most COAs, there’s an “Overall Status.” A “Pass” means the product meets safety standards. A “Fail” means it may be unsafe to use.
NOTE: Not all labs test for every category. If the COA says “Not Tested” for something like residual solvents, it’s a good idea to ask why—especially if the product is a concentrate, since solvents are often used during extraction.
Moisture Content and Water Activity
These tell you if the cannabis was dried and stored properly.
- Water Activity (Aw): Should be below 0.65 to prevent mold.
- Moisture %: Should usually be between 6–13%.
LOQ and LOD
You’ll often see values like “<LOQ” or “<LOD.” Here’s what they mean:
- LOQ: Limit of Quantification – the smallest amount the lab can measure with accuracy.
- LOD: Limit of Detection – the smallest amount the lab can detect at all.
- “<LOQ” means there’s so little of the substance, it couldn’t be measured.
Batch, Lab, and QR Code
- Check that the lab license number is listed.
- Look for a QR code or web link to verify the results.
- Batch and product names should match your packaging.
Importance of Testing
Testing helps protect your health and makes sure the cannabis product is what it says it is. In legal markets, all products must be tested and properly labeled so you know what you’re getting.
Final Tips for Reading a COA
- Always match the COA to the product label: check name, batch, and THC/CBD values.
- Look for state-certified labs and third-party testing.
- Use the QR code on your product to find the real COA.
- If anything looks off, ask the dispensary or contact the brand.
- Always read the COA before using a cannabis product.
- Check that test results match what’s on the label.
- Ask questions if something seems off and dispensaries should help explain.
- Look for third-party testing rather than for in-house lab results.
By understanding how to read a COA, you become a more confident and informed cannabis consumer. Whether you’re using cannabis for wellness, recreation, or medicine, the COA is your best tool for finding cannabis products that are safe to consume, accurately and honestly labeled, and thoroughly tested for strength, purity, and harmful contaminants. COAs support transparency and help build trust between consumers, producers, and regulators, contributing to a safer and more reliable cannabis industry.
The NYS Office of Cannabis Management (OCM) has a very comprehensive guideline on how to understand a COA: https://cannabis.ny.gov/system/files/documents/2023/04/ocm_howtoreadcoa_final.pdf
