Approach helpful for differentiating hemp- and marijuana-derived plant products: A review.

Cheng Y. · Forensic science review · 2026

**Background & Methods** This is a narrative review article examining current analytical methods and approaches for differentiating legal hemp-derived products from illicit marijuana in forensic and clinical laboratory settings. The review synthesizes literature on morphological, chemical, and genetic classification techniques used across forensic laboratories, law enforcement, and medical applications in the United States. **Key Findings** • Gas chromatography (GC)-based methods remain the gold standard in forensic laboratories for cannabis classification due to long-standing implementation in drug analysis, high efficiency, and cost-effectiveness, though liquid chromatography (LC)-based approaches offer advantages by avoiding thermal artifacts and enabling direct quantification of both acidic and neutral cannabinoids. • Multiple analytical techniques including direct analysis in real time (DART) and spectroscopy can enhance analytical efficiency; however, each approach has specific limitations, and the expanding landscape of hemp-derived cannabinoids creates significant challenges for accurate analysis and forensic interpretation. • DNA-based approaches using synthase-gene markers, simple sequence repeat (SSR) markers, and organelle markers provide stable, environment-independent alternatives for differentiation, but forensic implementation remains limited by insufficient genetic databases, assay complexity, and laboratory resource constraints. **Dosage & Administration** Not reported. **Safety & Adverse Effects** Not reported. **Evidence Quality** As a narrative review rather than original research, this article represents lower-level evidence (Level 4-5) and does not assess clinical safety or efficacy. The review's primary limitations include reliance on existing literature without systematic methodology, lack of original data, and focus on forensic laboratory applications rather than clinical outcomes. The authors acknowledge that each analytical approach has particular constraints and that continued method development requires careful validation. The review highlights critical gaps including insufficient forensic DNA databases for cannabis species differentiation, practical laboratory resource limitations, and the need for standardized validation protocols. The authors appropriately emphasize the importance of understanding method-specific limitations and ensuring rigorous evaluation to support defensible cannabis testing in forensic contexts. The findings are relevant for laboratory implementation but do not provide clinical evidence regarding cannabinoid safety or therapeutic applications.

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