ADH Requirements

Per the medical marijuana commission (“Schedule 2a” of cultivation applications), the following tests are required:

o Potency of marijuana (measurements for THC, THCA, CBD, and CBDA)
o Microbiological contaminants
o Pesticides
o Solvents
o Water activity and moisture content
o Metals

We can test for these, as well as other important characteristics, such as Terpene content. See our panel of tests below.

Our Validated Methods

Our scientific panel has extensively researched testing methodologies. We have chosen sensitive methods that use our top–of-the-line instruments. These were developed by some of the top labs in the nation and assure our results are within industry standards. Each method will be approved by ISO, the International Organization for Standardization. We use the accreditation body Perry Johnson. For an additional layer of quality assurance, our in-house analytical chemist (PhD) routinely reviews all protocols and testing operations.


Testing for Cannabis Flower

Potency Testing

To quantify the cannabinoid content of medical cannabis, Marygold Laboratories uses High Performance Liquid Chromatography (HPLC). We look for five major components to quantify and qualify the total potency of the dried cannabis product: measuring the amount of total Tetrahydrocannabinol (∆9THCA + ∆9THC + ∆8THC), Cannabidiol (CBDA + CBD), Cannabinol (CBN), Cannabigerol (CBGA +CBG), and Cannabichromene (CBC). These components allow the laboratory to determine the “strength” of the cannabis product. By knowing the total composition of the active ingredients, and their proportions, patients can then benefit by picking strains with active ingredients best suited for their medical condition.

Pesticide Testing

MaryGold Laboratories utilizes High Performance Liquid Chromatography with Mass Spectrometry (HPLC-MS) and Gas Chromatography – Mass Spectrometry to identify and quantify pesticides that remain on the product from the cultivation process. The cannabis is also tested for banned pesticides in order to verify that the product is safe for human consumption. By law, only trace amounts of pesticides are allowable, well below levels that would be harmful to patients.

Microbiological Contamination

While Cannabis is generally not considered dangerous, bacteria that grow on marijuana can be. In order to prevent bacterial infections and disease, marijuana is tested using sterile microbiological techniques. The degree of bacterial growth and the type of bacteria present is determined.

Per Arkansas regulations, Marygold tests for coliform bacteria. If any are detected, E. coli must specifically be tested for. A batch of marijuana fails testing if there are more than 100 colony-forming units.

Additional tests are available should you desire more stringent analysis. For example, clients may also wish to test for Salmonella, another potentially-dangerous type of bacteria commonly tested for in Cannabis.

Water Activity and Moisture Content

Cannabis with the wrong amount of moisture and water activity is a welcoming host for microbial contamination. Storage and packaging are particularly vulnerable, so prior testing is required for safety.

Water activity is a measurement of the water available for bacterial and fungal growth. The “Aw” value ranges between 0 and 1. At values above .6, some growth can occur. Thus, by state regulations, Aw values over .65 fail the batch.

Moisture content refers to the concentration of water in a Cannabis sample. Ideal moisture content is 10-15%. Below 10%, the product tends to crumble; a value over 15% must be reported but does not fail the sample.


Mycotoxins are produced by molds and fungi. In order to ensure that the cannabis products are free of fungi, the product undergoes visual inspection under a high-powered microscope. Then, using High Performance Liquid Chromatography (HPLC), the Lab tests for mycotoxin content within the dried cannabis.

These tests are conducted in order to ensure the safety of the product to the consumer. This especially applies to patients whose immune systems have been compromised, as many MMJ patients are likely to be, and patients who have lung impairments or mold allergies.


Exposure to toxic substances can jeopardize the health of medical marijuana patients. Among the list of dangerous contaminants are heavy metals, when in a high enough dose.

Metals are usually present in fertilizer. Growing Cannabis plants absorb these metals. Patients who use this Cannabis are then exposed to the contaminants, which accumulate in the body and are difficult to remove. It is crucial that any contaminants present in the fertilizer, and subsequently the plant, are in low amounts.
Cannabis, by law, is allowed to contain a very small amount; at levels too high, the product is deemed dangerous and fails the test.

Per Arkansas regulations, inorganic Arsenic, Cadmium, Lead, and total Mercury must be tested for.

For clients seeking more rigorous standards, testing for additional metals and chemicals is available upon request.


Terpenes are fragrant oils that give herbs, fruits, and many plants, including Cannabis, their diverse odors. Each type of terpene has a particular aroma, therapeutic effect, and potential medical benefit. Thus, testing for terpenes has become commonplace because of its interest to patients. To quantify terpenes in medical marijuana, Marygold Lab uses head-space gas chromatography and mass spectrometry. While not required by state law, we recommend terpene profiling for all clients.

Some common terpenes found in Cannabis are listed below:
Limonene, Myrcene ,Linalool, Alpha Bisabolol, Delta3 Carene, Borneol, Alpha-Pinene, Eucalyptol, Terpineol, Caryophyllene, Camphene.

Testing for Extracts and Edibles 

Residual Solvents Tetsing

MaryGold Laboratories utilizes Gas Chromatography with Flame Ionization Detection(GC-FID) to identify and quantify traces of residual solvents in cannabis extracts and concentrates at the part per million (ppm) level. The test ensures that the solvents (butane, propane, hexane, ethanol, and isopropanol) used in extraction remain in the final extracted product at safe levels only. 

Per Arkansas regulations, product is exempt from solvent testing if:

1) a mechanical extraction method was used in place of a solvent.

2) the solvent was water, animal fat, or vegetable oil.


Homogeneity testing determines if the potency of edibles and extracts is uniform throughout the product. Marygold tests several sites on the sample using High Performance Liquid Chromatography (HPLC) and compares their THC and CBD levels. Unvarying distribution is essential to ensure that a patient will be receiving the advertised amount of THC and CBD on the package label.