Hemp Investigation: Our Methodology

In December and early January, Assembly reporters purchased 21 hemp products from North Carolina convenience stores, dispensaries, and other retailers for testing. Locations and products were largely chosen at random, with a few exceptions. 

We intentionally purchased two products from Southern Ease Trading Company, a Nash County manufacturer that until last year was run by state Rep. John Bell, chair of the House Rules Committee and one of the General Assembly’s strongest hemp industry advocates. 

We also purchased two products from Naternal, a Morrisville-based company founded by Garrett Purdue, son of former Gov. Bev Purdue. His mother has appeared in ads for the brand. 

We tested four products from the Florida-based Chronic Guru, which was more than we’d planned. A budtender at Chronic Guru’s Durham dispensary gave our reporter two freebies for being a new customer and spending more than $50. 

We stored our purchases in their original packaging in our Durham office until mid-January, when an editor drove them to Richmond, Virginia, for testing. 

We’d contacted the Laboratory for Forensic Toxicology Research at the suggestion of colleagues from a partner newsroom. The director, Michelle Peace, first became known for her research on nicotine vaping, which led her to begin testing cannabis products.  

The National Institute of Justice, an arm of the U.S. Department of Justice, awarded her lab an ongoing grant in 2023—totaling more than $726,000 so far—to study the best ways to analyze THC. Her research has also informed Virginia’s policies. Peace previously served on the state’s Cannabis Control Authority. 

The lab analyzed our products’ cannabinoid content using liquid chromatography with mass spectrometry. It used gas chromatography with mass spectrometry to assess the chemical composition of the products, and 3M Petrifilm plates to detect yeast and mold, aerobic bacteria, E. coli, and coliform, which were evaluated against pass-fail thresholds established by U.S. Pharmacopeia.  

We received preliminary results on March 23. The lab then ran additional tests on five products that contained synthetic cannabinoids and retested products that showed unexpectedly low THC levels. We received the final results on May 8. 

We located manufacturer-supplied certificates of analysis for 15 of the products to compare with our results. All but two stated that the products contained legal amounts of delta-9.