Summer Parker didn’t understand why. She just knew she didn’t feel right.
“I’m not coherent, I’m not speaking correctly,” Parker said. “I try to open the door to the car thinking I’m going to try to stand up. I collapsed, lost consciousness, had to have EMSA come get me.”
She didn’t immediately connect it to the marijuana pre-roll she had just smoked. But after it happened other times, and each time was just after smoking a pre-roll produced by Graves Farm Organics, she and her partner, Charles Hrabina, submitted samples of the company’s medical marijuana products to a testing laboratory.
According to the couple’s lawsuit, filed in Tulsa County District Court against the company, the results showed five pesticide test failures, one for microbial contaminants, and one finding that it was less potent than the producer described.
Attorney Felina Rivera, who represents Graves Farm Organics and its owner, Michael Graves, denied her clients’ products had anything to do with Parker’s symptoms, or that there was anything wrong with the pre-rolls produced by the company.
But she does agree with Parker about one thing: There’s something very wrong with the system for testing cannabis products in Oklahoma.
“If you take a product to seven different labs, you’re going to get seven different results,” Rivera said.
Disputes over inconsistent results, laboratory oversight and the scope of required testing have raised questions about whether the system is delivering the reliability patients expect.
The debate has drawn together an unusual group of voices: patients who say contaminated products harmed them, laboratory operators who argue testing standards have improved, researchers who question whether current safeguards go far enough and regulators who have spent the past several years trying to standardize testing across one of the nation's largest medical marijuana markets.
Every legal medical marijuana product sold in Oklahoma must pass through a licensed testing laboratory before reaching consumers. State law requires laboratories to test samples from each final harvest or production batch for seven categories: microbials, mycotoxins, residual solvents, pesticides, cannabinoid potency, terpenes and heavy metals. Products that fail contaminant testing cannot legally be transferred to dispensaries.
Laboratories operate under licenses issued by the Oklahoma Medical Marijuana Authority and must obtain accreditation, participate in proficiency testing programs and comply with state standards governing testing procedures, quality control and recordkeeping. State law also requires laboratories to maintain policies designed to prevent financial or commercial interests from influencing test results.
The testing process culminates in a certificate of analysis, commonly called a COA, that documents whether a product passed required screening and reports information such as potency and contaminant results. State regulators may require products to be submitted for testing and are authorized to inspect laboratories, review underlying testing data and audit compliance.
Lab Shopping and the Search for Favorable Results
At the center of Oklahoma's cannabis testing debate is a simple question: if two laboratories test the same product, should they get the same result?
According to Marion McNabb, a public health researcher who serves as president of the Cannabis Center of Excellence, the problem comes down to the economics of Oklahoma’s cannabis market.
“Lab shopping is exactly the core of the problem,” McNabb said.
Tetrahydrocannabinol is the primary psychoactive compound in cannabis. Because many consumers use THC percentage as a shorthand for product strength, even relatively small differences in reported potency can influence demand and price.
Yasha Kahn, vice president of Massachusetts-based MCR Labs, said the issue extends well beyond Oklahoma and was blunt about how common lab shopping is.
“An honest lab in a state where there’s any dishonest labs will not be profitable,” Kahn said.
Keeping the Labs Honest
Keeping laboratories honest is the Oklahoma Medical Marijuana Authority's job.
OMMA Communications Director Carmin Acupan said in a written statement that lab shopping remains an issue in medical marijuana programs across the nation, but added that rigorous oversight can help expose and mitigate this practice.
Since Oklahoma’s medical marijuana program began, OMMA has taken enforcement actions against 29 independent testing laboratories. The agency also acknowledged that some laboratories failed proficiency testing and were required to take corrective action within 30 days.
Senate Bill 813, passed in 2023, authorized OMMA to establish and operate its own quality assurance laboratory as part of its oversight of Oklahoma’s medical marijuana testing system. The lab is intended to independently verify testing results and evaluate laboratory performance.
Three years later, however, the laboratory is still working toward full accreditation and has conducted only preliminary testing on a small number of products, with results still under review.
The laboratory is accredited to test for potency and pesticides in marijuana flower, oil and concentrates. It is now working on full accreditation in other areas, including heavy metals, microbial contamination, mycotoxins and residual solvents. If successful, it will begin full testing this year, Acupan said.
Once fully accredited, OMMA’s QA lab will conduct three types of oversight. Round-robin testing will compare identical samples across multiple laboratories to measure consistency. Parallel testing will independently analyze products involved in complaints or targeted investigations. Proficiency testing will evaluate whether licensed laboratories are using appropriate, accurate and consistent testing methods.
OMMA also operates a secret shopper program authorized by the legislature in 2022. Under the program, investigators purchase cannabis products from licensed dispensaries and submit them to multiple licensed laboratories, including the agency’s own quality assurance laboratory, for testing. The Office of Investigations and Enforcement visited 52 dispensaries during the program’s first year in 2024. Beginning in 2025, state law required the agency to randomly inspect at least 10% of licensed dispensaries each year.
Other Tests, Other Concerns
Unlike inflated THC numbers, inaccurate contaminant testing raises concerns that extend beyond marketing claims to patient safety.
For Summer Parker, those concerns became personal.
"We just kept testing," Parker said. "I think we went hard and tested probably 40 products in two years. We tested other companies too. Not just Graves."
Parker and Hrabina became advocates. They founded Patients for Safe Access of Oklahoma, a patient-led organization that encourages independent testing of medical marijuana products and advocates for stronger laboratory oversight. At one point, she said, products were sent to a California laboratory capable of screening compounds beyond Oklahoma's required testing panel.
"They found 19 different chemicals," Parker said, referring to compounds she said were not included in Oklahoma's standard pesticide screening.
Researchers said Parker's experience reflects a broader debate over whether Oklahoma's required testing panel adequately addresses the contaminants patients are most likely to encounter.
Are Oklahoma Laboratories Testing Enough?
Even if laboratories consistently produce the same results, another question remains: Are they testing for enough contaminants in the first place?
Oklahoma requires licensed laboratories to screen medical marijuana products for 28 pesticide analytes, up from 13 before March 1.
That question prompted Rep. Jacob Rosecrants, D-Norman, to file House Bill 3013, which would have expanded Oklahoma's required pesticide screening panel to 72 compounds, a number developed with laboratory experts and by reviewing pesticide screening requirements in other states.
House Bill 3013 never advanced from committee. Rosecrants said the proposal encountered questions from legislators and OMMA, and after discussions with House Alcohol, Tobacco and Controlled Substances Committee Chairman Rep. TJ Marti, he agreed to pursue an interim study instead.
"We need to educate folks at the Capitol before pushing legislation," he said.
Outside the Regulated Market
The debates over laboratory testing, pesticide screening and quality assurance apply only to products sold through Oklahoma's licensed medical marijuana system.
Outside that system, consumers may encounter intoxicating hemp-derived cannabinoids such as delta-8 THC, delta-10 THC, THC-O and HHC, sold in convenience stores, smoke shops and other retailers.
Mark Woodward, public information officer for the Oklahoma Bureau of Narcotics and Dangerous Drugs Control, said OBN does not consider products containing THC in any form to be legal outside of the regulated system.
"We don't believe it's a gray area and we believe it is clearly regulated in statute," Woodward said. "If it's got tetrahydrocannabinol in it, which these do, it's a controlled substance and cannot be sold in gas stations."
Woodward said OBN has responded to complaints by visiting retailers and advising them that such products may violate Oklahoma law. In many cases, he said, stores voluntarily removed the products after speaking with agents.
"A lot of them have been told that it's a legal product," Woodward said, referring to information retailers received from distributors or sales representatives.
For consumers, the distinction is significant. While experts continue to debate whether Oklahoma's regulated medical marijuana testing system is consistent enough, products sold outside that system are not subject to the same testing requirements, regulatory oversight or consumer protections.
Oklahoma Watch, at oklahomawatch.org, is a nonprofit, nonpartisan news organization that covers public-policy issues facing the state.
