Addressing the Sources of Variability in Cannabinoid Content Testing: A Collaborative Study on the Role of Reference Materials

Independent and accurate testing of cannabinoid content in cannabis is essential for regulatory compliance, pricing and taxation, market integrity, label claim verification, and consumer transparency. However, inconsistencies seen in recent data from cannabis testing laboratories present challenges in these critical areas. To address the potential sources of variability among laboratories, the Cannabis Working Group (CWG) of the American Council of Independent Laboratories (ACIL) initiated a collaborative study involving cannabis testing labs and certified reference material (CRM) producers.

This blind study engaged five independent, accredited cannabis testing laboratories from the U.S. and Canada, which analyzed reference materials for various cannabinoids sourced from five distinct manufacturers. Utilizing a common standard operating procedure, the laboratories prepared standard solutions to quantify the cannabinoids against a standard curve.

In this presentation, we will explore the inter- and intra-laboratory variation for different cannabinoids and standards, identifying potential sources of discrepancies. Additionally, we will discuss the broader impacts of laboratory testing variability and the importance of establishing comprehensive laboratory best practices within the current cannabis regulatory landscape. The findings from this study aim to inform regulatory frameworks and guidance for independent cannabis testing laboratories, ultimately contributing to more reliable cannabinoid content reporting.