Analysis of Illicit Street Heroin Seized in Pakistan by Gas Chromatography-Mass Spectrometry (GC-MS) for Identification of Adulterants and Impurities.

Heroin abuse poses a significant public health and law enforcement challenge globally, with concerns in Pakistan due to the prevalence of illicit street heroin and limited data on its composition. This study analyzed 706 heroin samples seized between 2017 and 2022 using gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR) to determine their chemical composition. The results revealed that street heroin in Pakistan is extensively adulterated with a variety of pharmaceutical agents, including acetaminophen, caffeine, diazepam, and dextromethorphan. Pareto analysis demonstrated that a small subset of adulterants accounted for most of the street samples, with caffeine, acetaminophen, and diazepam present in nearly 90% of analyzed samples. Impurities from incomplete synthesis, particularly 6-monoacetylmorphine (97%) and acetylcodeine (95%), were also widespread. Some samples contained only adulterants, lacking heroin entirely. The widespread adulteration and presence of pharmacologically active impurities significantly increase the risk of toxicity and complicate clinical management of overdoses. These findings highlight the urgent need for drug monitoring and regulation, as well as targeted public health interventions. The comprehensive chemical characterization of street heroin provides valuable insights for forensic investigations, policy development, and epidemiological surveillance to address the evolving risks associated with illicit heroin use in Pakistan.