Description of original award (Fiscal Year 2021, $161,031)
With the passage of the Agricultural Improvement Act of 2018, which legalized hemp, the presence and use of cannabinoids has seen an exponential growth. This growth is not with just THC and cannabidiol (CBD), but with many emerging potentially psychoactive analogs (e.g. Delta-8 and Delta-10 THC) with abuse potential. This presents a detectability issue in all urine drug testing scenarios. The issue is can current screening methods detect these analogs and/or their biological metabolites. Screening is the initial step of testing. Delta-9 THC-Carboxylate (THC-COOH) has been the standard compound for cannabinoid testing. In 1994, federal regulations lowered the screening cutoff for THC-COOH to 50ng/mL to increase the detection of potential THC abuse, 20ng/mL is used in some scenarios. Little is known of THC analogs’ cross-reactivity, and less is known of the analogs’ urine metabolites cross-reactivity. This project will evaluate the ability to detect (limit of detection) and the precision around that concentration of commercially available homogeneous immunoassays cannabinoid assays (HEIC) to detect THC analogs (Delta-8 & Delta-10 THC, and CBD) and their metabolites. If metabolite standards are not available, they will be synthesized and verified using a laboratory published liver microsome method. No human subjects will be involved, only commercially available urine matrix. The project will be conducted at the Virginia Commonwealth University’s VCU Health campus and will be 12months in length. Initially (3-4months), HEICs will be obtained, setup and verified according to the manufacture’s parameters and procedures. Secondly, (5-6months), analytical standards of the analogs and metabolites will be obtained, or synthesized. The compounds will be fortified individually in human urine, at 20, 50, 100 and 1000ng/mL, to determine if they are detectable by the HEICs. If the compound is not detectable, then no further testing will occur. If detectable, the compound will be evaluated for limit of detection and precision around the decision point (cutoff) using ASB Standard 036 for qualitative testing. Finally, the results of the testing will be compiled by compound, HEI manufacture, cutoff concentration (20 or 50ng/mL), and sensitivity and specificity. The results will be prepared for presentation at annual forensic science meetings, and a potential manuscript. The results of this project will increase the knowledge of the forensic science community, by increasing the basic understanding and capabilities of current homogeneous cannabinoid immunoassay screening assays to detect the increasing number of THC analogs being encountered.