Multivariate classification based on chemical and stable isotopic profiles in sourcing the origin of marijuana samples seized in Brazil

• Autor(a) principal: Shibuya,Elisa K.
• Data de Publicação: 2007
• Outros Autores: Sarkis,Jorge E. S., Negrini-Neto,Osvaldo, Ometto,Jean P. H. B.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532007000100024
• topic: forensic science; drug sourcing; marijuana; chemical fingerprint; linear discriminant analysis

The main task of this work was to verify the existing differences in the elemental composition of samples seized in the main Brazilian regions of marijuana production, previously separated by their carbon and nitrogen stable isotope results, and to use these differences to classify the samples according to their geographical origins. The sector field inductively coupled plasma mass spectrometry technique (HR-ICP-MS) was the analytical technique applied and the data analysis was performed using hierarchical cluster and linear discriminant analysis. Results indicate that samples from different regions present different chemical profiles that appear in accordance to the geological characteristics of each region. The most relevant parameters were carbon and nitrogen stable isotopes, copper, cobalt, barium, lanthanum, zinc, iron, yttrium and manganese. An interesting product of this work was to demonstrate the possibility of using seized samples to create a national databank for monitoring the geographical origin of marijuana consumed in the country.