Bulk and compound‐specific isotopic characterisation of illicit heroin and cling film

Abstract

Comparative analysis involves various but complementary methods and can be used for forensic intelligence purposes to group seizures of heroin into batches. Much forensic analysis now combines expertise in the traditional area of drugs investigation with a detailed understanding of supply, packaging, distribution, and drugs intelligence. It was the intention of this research to determine whether illicit heroin seizures and packaging material can be grouped according to isotopic compositions, and to explore factors that affect the isotopic compositions. In order to achieve these aims, 14 samples of seized heroin, thirteen provided by Avon and Somerset Constabulary (UK), were analysed by elemental analysis/isotope ratio mass spectrometry (EA/IRMS) and gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) for carbon and hydrogen isotopes. These tests elucidated that a combination of the delta13C, delta15N, delta18O and delta2H results from EA/IRMS is able to distinguish between most samples of bulk heroin. We speculate that the delta13C values of the alkaloids, obtained by GC/C/IRMS, give indications of different geographical or temporal origins of some of the heroin samples. GC/C/IRMS of the cutting agent, caffeine, provides a means to link dilution events. Fifteen retail cling film samples and seven cling film samples from heroin seizures were analysed by EA/IRMS. A multivariate comparison of the carbon, hydrogen and oxygen isotope ratios was able to distinguish between most of the samples. This technique enabled the cling films from the heroin to be grouped according to seizure. Three solvents were tested on two samples of cling film of known composition. Methanol and chloroform were both found to extract material from PVC and from non-PVC cling films. Water-treated PVC was indistinguishable from the untreated PVC and thus water was found to be the most suitable solvent when washing cling film prior to IRMS analysis.

Stable isotope ratio mass spectrometry and physical comparison for the forensic examination of grip-seal plastic bags

“…The overall range of carbon isotopic composition, excluding grip-seals, was found to be À28.6 to À37.2%, significantly wider than determined from the initial study, but consistent with the range previously determined for PE cling film [4]. The overall range of hydrogen isotopic composition was found to be À46 to À70%, significantly less than determined in the initial study.…”

“…The overall range of carbon isotopic composition was found to be from À27.2 to À32.1%, significantly less than previously determined for PE cling film [4]. The overall range of hydrogen isotopic composition was found to be from À48 to À105%.…”

“…Previous studies have also shown that washing of plastic samples is only required if foreign substances are present on the surface, e.g. drug residues [4]. Samples were, therefore, cut from bags and analysed without further treatment.…”

“…Grip-seal bags were originally developed by Dow Chemicals as Ziploc TM bags [3] and are known by many other names such as zip lock bags or resealable bags. Previous research has demonstrated the potential of isotope ratio mass spectrometry (IRMS) to characterise packaging materials such as cling film [4] and pressure sensitive adhesive tape [5] via the stable isotopic composition of these materials or their constituents. An increased interest in forensic applications of IRMS has lead to the publication of a number of reviews [6,7].…”

Deuterium‐ und tritiummarkierte Verbindungen: Anwendungen in den modernen Biowissenschaften

“…[106] Entsprechend hat sich die Analyse der natürlichen Isotopenverhältnisse,z.B.durch IRMS (isotope ratio MS), [107] IRIR (isotope ratio IR) [108] oder ICP-MS (MS mit induktiv gekoppeltem Plasma), [109] als eine wirkungsvolle Methode in der Forensik, der Geochemie,der Paläoklimatologie,der Ökologie und der Physiologie etabliert. B. die Herkunftsermittlung und Echtheitsprüfung von Lebensmitteln, [111] Wasser, [112] Schadstoffen [113] und Pharmazeutika, [114] die Charakterisierung von Arzneimitteln [115] und Sprengstoffen [116] und die Spurenanalyse von Boden-und Wasserverunreinigungen. B. die Herkunftsermittlung und Echtheitsprüfung von Lebensmitteln, [111] Wasser, [112] Schadstoffen [113] und Pharmazeutika, [114] die Charakterisierung von Arzneimitteln [115] und Sprengstoffen [116] und die Spurenanalyse von Boden-und Wasserverunreinigungen.…”