Sourcing Cannabis sativa L. by thermogravimetric analysis

Marijuana, dried and ground Cannabis, is the most consumed illicit drug in the world. Many undesirable and risky effects to human health are caused by its use. The medicinal use or legal recreational use of Cannabis has also been rising in many countries. These facts make traceability methodologies increasingly important whether for forensic use, such as drug trafficking eradication, or for quality control purposes of legal medicinal Cannabis. Consequently, the objective of this study was to analyze Cannabis by means of thermogravimetric analysis (TGA) in order to assess the capability of this technique to trace the geographical origin of Cannabis cultivated in Colorado, United States of America. TGA appears to be sensitive enough to detect the degradation/decarboxylation of cannabinoids and terpenes, at least to some extent; also, the degradation of cellulose, hemicellulose and lignin was indicated. Overall, the temperature ranges we analyzed using linear discriminant analysis showed high accuracies, with the 200 to 300 °C and 600 to 700 °C ranges achieving 100% accuracy.