Behind the scenes at a cannabis testing lab

A tour of Green Leaf Lab, the first cannabis lab in Oregon to receive state accreditation.  The first in a two-part series. 

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As of Oct. 1, cannabis growers, producers and dispensaries have had to adhere to stringent state testing requirements. Products have to be tested for pesticides, solvents, potency and water activity. (Labs test for water as an indicator of potential microbial growth.) 

“It’s been an adjustment period for the producers and manufacturers,” said Eric Wendt, chief science officer of Green Leaf Lab. “[The rules are] designed to have greater control over the product reaching the customer.”

Wendt says the new tests are working the way they were supposed to. There is less variability from product to product, he said.

“The first chocolate bar made and the 10,000th chocolate bar made are the same,” Wendt said. 

The consistency is largely due to the changes in sampling. The state now mandates representative sampling.

“Before there were no requirements,” Wendt said. “A grower could grow 10 pounds and bring in a three gram sample and say, ‘This will represent my product.'”

New regulations for growers came with new regulations and standards for labs like Green Leaf. Wendt said he spent eight months preparing equipment, hiring staff and developing protocols for testing. The lab itself is nondescript, tucked away in a business park near Parkrose High School in outer Northeast Portland. A staff of 18 usher samples through a series of machines and small rooms just large enough to house machines with $500,000 price tags. 

Here are photos from the tour showing how Green Leaf tests cannabis samples.  Check back next week for Part II: a look at the regulatory challenges facing cannabis labs (like Green Leaf), as well as lab employees at the vanguard of the new industry. 

2Cannabis samples are processed to create a homogenous liquid. That liquid is then used to test for residual solvents, pesticides and potency.


3A cannabis sample in the middle of the processing cycle. 


5An intake room 

6A gas chromatography machine tests for solvents and terpenes.

7This piece of equipment looks like a printer, but it’s actually one of two machines used to test for pesticides.

8A sample used in the gas chromatography machine.

9A liquid chromatography machine tests for pesticides. 

10The last step: testing for potency