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Cannabis Quality Assurance Program: Exercise 2 Toxic Elements Final Report



Chuck Barber, Colleen E. Bryan Sallee, Carolyn Burdette, Shaun Kotoski, Melissa M. Phillips, Walter Brent Wilson, Laura Wood


In 2020, NIST launched CannaQAP to improve the comparability of the analytical measurements of cannabis and cannabis-derived products in forensic and cannabis (hemp and marijuana) testing laboratories. CannaQAP is an interlaboratory study mechanism that is similar to a proficiency testing scheme; however, the focus is towards education without assigning pass/fail grades to the anonymized participants. CannaQAP helps inform NIST about the current measurement capabilities of, and challenges faced by the analytical cannabis community. This in turn assists NIST in the design and characterization of cannabis reference materials (RMs). This study of CannaQAP Exercise 2 focused on the determination of toxic elements in two hemp materials and a control material provided by NIST. Arsenic, cadmium, lead, mercury, beryllium, cobalt, chromium, manganese, molybdenum, nickel, selenium, uranium, and vanadium were the toxic elements chosen based on interest expressed by the cannabis community. This report provides a detailed description of the results of this study.
NIST Interagency/Internal Report (NISTIR) - 8452
Report Number


Arsenic, cadmium, cannabis, Cannabis Quality Assurance Program (CannaQAP), hemp, lead, mercury, toxic elements


Barber, C. , Bryan Sallee, C. , Burdette, C. , Kotoski, S. , Phillips, M. , Wilson, W. and Wood, L. (2022), Cannabis Quality Assurance Program: Exercise 2 Toxic Elements Final Report, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed April 19, 2024)
Created December 15, 2022