CBD-Infused Foods, Drinks Testing: Here’s Where it Stands

Two main testing methods currently are used for cannabis: DNA-based and growth-based methods. Growth-based methods involve plating so the microorganisms on the product can be grown, seen, and counted. The process can take weeks, but it is the gold standard in agriculture, Dr. Cassidy says.

Still, because it takes a while to grow microbes, that method has its limitations, she says. DNA-based methods are faster because they can detect microorganisms without requiring them to grow. “What we are doing is cracking open the cells of these microorganisms, getting the DNA, and quantifying it using fluorescence technology, which is extremely sensitive,” she says. CDX Analytics also tests for 12 cannabinoids.

Massachusetts, where her company is based, requires certain tests at certain parts of the process. While a plant-infused product will be tested for potency, microbials, and mycotoxins, the plant itself will be tested for those three plus metals. “We see a lot fewer microbes on processed products than we do on raw plant materials,” Dr. Cassidy says. “When you use an extraction process on a living plant the heat process helps kill any microbes that were present.”

If a test fails, the cannabis grower can have the product retested or remediated. Remediation options include using light or ozone treatments or extracting the cannabinoids from the plant, she says.

Some growers choose to conduct their own pretests before submitting their product to a lab like CDX Analytics, which adheres to state testing requirements. “Our tests are being used in testing labs, but some growers are also buying our products now so that they can do a pretest before they send it out to be tested,” says Heather Ebling, senior applications and support manager at Medicinal Genomics, a Beverly, Mass., company that makes quantitative PCR tests for testing labs to isolate DNA from a cannabis flower.

She says the pretests are a “heads up” as to whether or not the cannabis is going to pass, and if it’s not, to conduct some remediation to decrease the number of microbes that are present. “Once you get a failing test you can actually ruin a whole batch or crop. It’s pretty detrimental,” Ebling says. “Some states do allow remediation and they’ll let growers have a second chance.”

Like others in the cannabis industry, she recommends more species-specific testing of mold, yeast, and other microbes.

In Massachusetts the limit for a total yeast and mold test is 10,000 colony forming units (CFUs) per gram, she says. “So you could have 9,000 CFUs of Aspergillus and it still will pass,” she says. “But you don’t know if its Aspergillus because while the microbe is triggering your total yeast and mold test, the test isn’t telling you what the microbe is.”

Remediating Cannabis

There are many products and techniques on the market that can help with remediation. Some are used as preventive measures, as a last step before the cannabis is tested. Others are used after a test fails.

The most common and cost-effective technique is to process the plant and extract the THC or CBD or both, says DeGabrielle. “That removes everything except the desired elements from the plant materials,” he says. “Using fractional distillation, you can essentially remove impurities.” It’s a common technique in any type of agricultural product extraction, he adds.

Willow Industries, a Denver, Colorado-based cannabis remediation and decontamination company, sells systems that use ozone to mitigate mold and bacteria by essentially introducing a kill step. “Cultivators typically implement our technology as the last step in their production process, and then they send the product out to be tested to the licensed lab,” says Jill Ellsworth, founder and CEO of Willow Industries. She says the ozone gas degrades microbial contaminants on the product.