OMMA recently sent notices (linked below) regarding safety concerns with products tested by Greenleaf Labs for total yeast and mold between 2023 and 2025. This message serves as a follow-up to the agency’s previous communication. 

Greenleaf Labs Ordered to Cease Operations Following Product Safety Concerns (Aug. 8) 
Notice to Dispensaries Regarding "Test Failed" Products in Their Metrc Inventory (Aug. 13) 

Greenleaf is actively working with its customers to conduct and pay for retesting, ensuring unsafe products are not sold to patients. Products that pass retesting meet safety standards and are compliant with OMMA Rules. Products that fail retesting can be remediated (processing failed marijuana into a solvent-based concentrate) or decontaminated (treatment to remove or reduce contaminants that exceed allowable limits). Whether products are remediated or decontaminated, they must pass required testing. Products that fail retesting and are not remediated or decontaminated by licensees are not safe for consumption. Products in “test failed” status do not meet safety standards and cannot legally be sold by dispensaries to patients. Products must be in “test passed” or “retest passed” status to be sold to patients. 

Patients who recently purchased products tested by Greenleaf should contact the dispensary they purchased from to verify that the products passed testing and are safe for consumption. Patients who have the batch number for their products can also contact Greenleaf directly at chris@greenleaf-labs.com. 

All products must undergo retesting before a recall can be completed. When all necessary steps have been taken, patients can verify the safety of their products by checking their packaging/product label for the batch number and comparing it to a product table listed on OMMA’s website. If a patient experiences an adverse health reaction after consuming a product tested by Greenleaf, they should contact their physician immediately and fill out OMMA’s Health Impact Form. 

OMMA will continue to share updates related to this matter. 

Greenleaf released the following statement: 

"Greenleaf Laboratories offers our sincere apology to our clients, partners, and regulators for the significant errors identified in the post-analysis data processing of Total Yeast and Mold (TYM) results. These errors––rooted in the implementation of a calculation change converting CQ to CFU/g––resulted in inaccurate Certificates of Analysis (CoAs) and confusion within the industry. 

Between April 2023 to July 23, 2025, we had samples that had quantifiable TYM detections that failed to meet compliance standards. This sharply contrasts with our prior failure rate and we have taken immediate steps to get back into compliance. We deeply regret the disruption and loss of confidence this has caused. 

Immediately upon identifying the issue, we acted in good faith to correct it––drafting a data recall procedure, validating calculations, and submitting the finalized recall to our LIMS vendor. Despite these efforts, technical execution of the recall was blocked by the vendor's refusal to assist. 

We accept full responsibility for the oversight and its consequences. This week alone, we have incurred over $85,000 in lost revenue and anticipate an additional $450,000 in costs to cover third-party retesting for impacted businesses. We also intend to fully comply with and pay any fines assessed by OMMA. 

In response, we have implemented the following corrective actions to ensure transparency, accuracy, and to prevent recurrence:

   • Conducted internal SOP audits and an external vendor audit to ensure process integrity.

   • Deployed updated quality control systems and software in the Micro Department to improve lot tracking and result reliability.

   • Adopted all vendor-recommended SOP revisions (GL-MSOP-11) as of August 14.

   • Implemented GL-SOP-28, a Vendor Communication Policy, to strengthen accountability and escalation protocols.

   • Initiated full reimbursement for affected clients and are covering the cost of retesting through an independent lab (Abraxis). 

In parallel, we are undergoing additional internal and external proficiency testing (PTs) for all safety analyses and will provide full documentation of validation and verification efforts upon completion. 

We understand that trust must be earned through action. Our commitment to scientific integrity, regulatory compliance, and client trust is unwavering. We will continue to cooperate fully with OMMA and provide all necessary documentation for review prior to public release of recall information. It is our intention when approved to issue a public statement on the recall of data, along with the full list of impacted samples. 

Again, we extend our deepest apologies to all those impacted."