The Italian panorama of cannabis light preparation: Determination of cannabinoids by LC-UV

Abstract

Cannabis light preparations are products derived or containing dried female inflorescences of Cannabis sativa belonging to Chemotype III (THC/CBD ratio <<1); the total THC (THC+THCA) content in the crop must not exceed 0.2 % in accordance with the EU regulation. In Italy the most recent law for industrial hemp (242/2016) states that only for farmers this limit is extended to 0.6 %. On the other hand, the Ministry of the Interior published a note stating that the sale or the presence in the markets of products (inflorescences, concentrates, essences and resins) or plants with concentrations higher than 0.5 % constitutes a crime. In this confusing legislation framework, it is very important to assess the legality of hemp, determining the total amount of THC. To this end a reliable LC-UV analytical method was developed and validated taking into account parameters such as precision, accuracy, linearity, repeatability of peak area and retention time, limit of detection (LOD= 0.002 % for all cannabinoids) and limit of quantification (LOQ= 0.005 % for all cannabinoids). Accuracy was expressed as the relative error (Er%), while precision was measured as the coefficient of variation (CV%). A CV% below 3 % and Er% between ± 6 % were obtained. The linearity was proven in the concentration range 0.005-1 % for THC, THCA and CBN and 0.005 %-50 % for CBD and CBDA. The analytical method was applied to more than nine hundred cannabis light samples. Based on the law 242/2016, only 18 % of the crops are to be considered legal for the market (total THC<0.2 %). If the circular of the Ministry of the Interior should be converted as a proper law, a substantial amount of cannabis light preparations (24 %) would be considered illegal (total THC>0.5 %). On the other hand, the most of the inflorescences (58 %) have a total THC content comprised between 0.2 % and 0.5 %, and it is not clear whether these products could be sold or not. Moreover, Cannabis light products are not authorized for human consumption, even if everybody knows that this is their primary use. In conclusion, the cannabis light panorama in Italy is quite confused and more specific and clear legislation should be proposed.

Keywords: Cannabinoids; Cannabis; Cannabis light; LC-UV; Shimadzu cannabis analyzer for potency.