An increasing source of illicit heroin, originating from the Golden Triangle or Afghanistan, has been shipped to other parts of Asia and to Oceania countries using Malaysian ports as transit hubs. Forensic drug profiling could provide useful information on the trafficking routes and the origin of drugs for intelligence purposes. This study is aimed at establishing the possible relationship among the heroin samples seized from different sources for predicting the trafficking network of illicit heroin in the northern region of Malaysia. One hundred and fifty-five seized heroin samples were analysed using Attenuated Total Reflectance-Fourier Transform Infra-red spectroscopy and the resulting spectral data points were subjected to chemometric procedures. Principal component analysis revealed the formation of four different clusters of illicit heroin: samples of high purity, samples cut with polysaccharide and caffeine, as well as samples of very low purity. Hierarchical cluster analysis grouped the samples into ten sub-clusters suggesting analytically distinguishable variability among the samples. In comparison, ten representative heroin samples seized from central regions of Malaysia gave significantly different profiles, separating them from those obtained in the northern region. This comparative information offers beneficial forensic intelligence to prove the existence of different clusters of trafficking networks.
Forensic science; illicit heroin; chemometrics; ATR-FTIR drug profiling