Examination of Firearms Review: 2007 to 2010 - Interpol

contributions to the overall combined uncertainties of MA and AP.
Appropriate specimen selection and collection is important for a successful
systematic toxicological analysis (STA). The Committee of STA published
guidelines to address the issue of sampling such as specimen types, amounts
that should be collected and submitted to laboratories expected to perform
STA, and criteria for ensuring quality assurance in sample collection [219].
3. Advances in Toxicological Analysis
3.1 Instrumental techniques
The first step of toxicological analysis is the identification of unknown drugs
and poisons in body fluids. A general unknown screening procedure is
necessary to enable simultaneous detection of as many intoxicants as possible.
Modern analytical and instrumental methods that were used in forensic
toxicology for both qualitative and quantitative analysis of drugs have been
reviewed [220]. The review focused on description of the theory, inherent
strengths, and limitations of various analytical instrumentation, including
GC-MSs, LC-MSs, mass spectrometers, and capillary electrophoresis
instruments, commonly used in forensic toxicology.
3.1.1 GC-MS
The applicability of a freeware deconvolution software AMDIS (Automated
Mass Spectral Deconvolution and Identification System) for GC-MS-based
systematic toxicological analysis (STA) in urine was evaluated [221]. It is
concluded that with the use of optimized settings, the AMDIS-based data
analysis was comparable or even superior to manual evaluation by an
experienced toxicologist, and reduced by half the overall analysis time.
Nevertheless, AMDIS can identify only targets present in the user-defined
target library, and may therefore not indicate unknown compounds that might
be relevant in clinical and forensic toxicology. A comprehensive GC-MS
screening method was developed for the detection of over 150 prohibited
substances on the list of the World Anti-Doping Agency, including anabolic
androgenic steroids, stimulants, and narcotic agents [222]. The analytes were
extracted from urine by LLE using diethylether and dibutyl ether at pH 9.5 and
14, respectively, followed by derivatization using a mixture of
N-methyl-N-trimethylsilyltrifluoroacetamide, NH4I, and ethanethiol, prior to
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