Chemical Profiling of Street Cocaine from Different Brazilian Regions

摘要

This work describes results of chemical profiling by gas chromatography with flame ionization detector (GC-FID) of the main components (purity, oxidation level, and cutting agents) in 642 street cocaine samples seized in five different Brazilian States between 2011 and 2014. The analysis revealed the presence of cocaine with mean content of 49.8%. Freebase samples showed cocaine average content of 66.0%, whereas hydrochloride and not determined (n.d.) present cocaine content of 44.5% and 11.8%, respectively. Cocaine base samples show moderately (16%) to not oxidized (81%) levels, whereas cocaine hydrochloride samples exhibit moderate (37%) to high (22%) oxidation degrees. Approximately 34% of all the analyzed samples did not have any adulterant identified. Base cocaine samples are even less adulterated (42% uncut) with phenacetin being present in 53% (average content of 15%). Caffeine and lidocaine were mostly found in hydrochloride samples, while the n.d. samples show a combination of either phenacetin or a caffeine/lidocaine mixture. A mass balance approach is presented and seizures information can be combined to deliver intelligence and statistical analysis that might contribute to the understanding of street cocaine composition scenario. A total of 269 samples were characterized as crack cocaine showing phenacetin as the main adulterant and presenting an average cocaine content of 68.3%.