Table of Contents
Cover
Title Page
Copyright
Series Foreword
Foreword by Dame Sue Black
Foreword by Commissioner Mark Harrison
Foreword to the 1st Edition
Book Endorsements
Preface to the 2nd Edition
List of Abbreviations
About the Companion Website
Introduction: Stable Isotope ‘Profiling’ or Chemical ‘DNA’: A New Dawn for Forensic Chemistry?
References
Part I: How it Works
Chapter I.1: What are Stable Isotopes?
Chapter I.2: Natural Abundance Variation of Stable Isotopes
Chapter I.3: Chemically Identical and Yet Not the Same
Chapter I.4: Isotope Effects, Mass Discrimination and Isotopic Fractionation
I.4.1 Physical Chemistry Background
I.4.2 Fractionation Factor α and Enrichment Factor ε
I.4.3 Isotopic Fractionation in Rayleigh Processes
Chapter I.5: Stable Isotopic Distribution and Isotopic Fractionation of Light Elements in Nature?
I.5.1 Hydrogen
I.5.2 Oxygen
I.5.3 Carbon
I.5.4 Nitrogen
I.5.5 Sulfur
I.5.6 Isoscapes
Chapter I.6: Stable Isotope Forensics in Everyday Life
I.6.1 “Food Forensics”
I.6.2 Authenticity and Provenance of other Premium Products
I.6.3 Counterfeit Pharmaceuticals
I.6.4 Environmental Forensics
I.6.5 Wildlife Forensics
I.6.6 Anti-Doping Control
Chapter I.7: Summary of Part I
References Part I
Part II: Instrumentation, Analytical Techniques and Data Quality
Chapter II.1: Mass Spectrometry versus Isotope Ratio Mass Spectrometry
II.1.1 Stability, Isotopic Linearity and Isotopic Calibration
Chapter II.2: Instrumentation for Stable Isotope Analysis
II.2.1 Dual-Inlet IRMS Systems
II.2.2 Continuous-Flow IRMS Systems
II.2.3 Bulk Material Stable Isotope Analysis
II.2.4 Compound-Specific Stable Isotope Analysis of Volatile Organic Compounds
II.2.5 Compound-Specific 13 C/15 N Analysis of Polar, Non-Volatile Organic Compounds by LC-IRMS
II.2.6 Compound-Specific Isotope Analysis and Forensic Compound Identification
Chapter II.3: Quality Control and Quality Assurance in Continuous-Flow Isotope Ratio Mass Spectrometry
II.3.1 Compliance with IUPAC Guidelines is a Prerequisite not a Luxury
II.3.2 The Identical Treatment Principle
II.3.3 The Importance of Scale Normalization
Chapter II.4: Points of Note for Stable Isotope Analysis
II.4.1 Preparing for Analysis
II.4.2 Generic Considerations for BSIA
II.4.3 Particular Considerations for BSIA
II.4.4 Points of Note for CSIA
Chapter II.5: Statistical Analysis of Stable Isotope Data within a Forensic Context
II.5.1 Chemometric Analysis
II.5.2 Bayesian Analysis
Chapter II.6: Quality Control and Quality Assurance in Forensic Stable Isotope Analysis
II.6.1 Accreditation to ISO 17025
II.6.2 The Forensic Isotope Ratio Mass Spectrometry Network
Chapter II.7: Summary of Part II
Appendix II.A: How to Set Up a Laboratory for Continuous-Flow Isotope Ratio Mass Spectrometry
II.A.1 Pre-Installation Requirements
II.A.2 Laboratory Location
II.A.3 Temperature Control
II.A.4 Power Supply
II.A.5 Gas Supply
II.A.6 Forensic Laboratory Considerations
II.A.7 Finishing Touches
Appendix II.B: Sources of International Reference Materials and Tertiary Standards
Appendix II.C: Selected Sample Preparation Protocols
II.C.1 Derivatization of Amino Acids for Compound Specific Isotope Analysis by GC-IRMS
II.C.2 Acid Digest of Carbonate from Bio-apatite for 13 C and Analysis
II.C.3 Preparing Silver Phosphate from Bio-apatite for 18 O Analysis
II.C.4 Two-Point Water Equilibration Protocol for Determination of Non-ex δ 2 H Values of Human Hair
Appendix II.D: Internet Sources of Guidance and Policy Documents
References Part II
Part III: Stable Isotope Forensics: Case Studies and Current Research
Chapter III.1: Forensic Context
III.1.1 Legal Context
Chapter III.2: Distinguishing Drugs
III.2.1 Natural and Semisynthetic Drugs
III.2.2 Synthetic Drugs
III.2.3 “Legal Highs” and “Designer Drugs”
III.2.4 Excipients
III.2.5 Conclusions
Chapter III.3: Elucidating Explosives
III.3.1 Stable Isotope Analysis of Explosives and Precursors
III.3.2 Potential Pitfalls
III.3.3 Conclusions
Chapter III.4: Matching Matchsticks
III.4.1 13 C-Bulk Isotope Analysis
III.4.2 18 O-Bulk Isotope Analysis
III.4.3 2 H-Bulk Isotope Analysis
III.4.4 Matching Matches from Fire Scenes
III.4.5 Conclusions
Chapter III.5: Provenancing People
III.5.1 Stable Isotope Abundance Variation in Human Tissue
III.5.2 Case Examples
III.5.3 Conclusions and Caveats
Chapter III.6: Stable Isotope Forensics of Other Physical Evidence
III.6.1 Microbial Isotope Forensics
III.6.2 Toxins and Poisons
III.6.3 Paper, Plastic (Bags) and Parcel Tape
III.6.4 Conclusions
Chapter III.7: Evaluative Interpretation of Forensic Stable Isotope Data
III.7.1 Not Scale Referenced δ -Values
III.7.2 Unresolved Contradictory Data
III.7.3 Foregone Conclusions
III.7.4 Logical Fallacies
III.7.5 Untested Assumptions
III.7.6 Conclusion
Chapter III.8: Summary of Part III
Appendix III.A: An Abridged List of Forensic Stable Isotope Laboratories Worldwide
References Part III
Recommended Reading
Books
Reviews
Author's Biography
Acknowledgements
Index
End User License Agreement
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Guide
Cover
Table of Contents
Begin Reading
List of Illustrations
Chapter I.2: Natural Abundance Variation of Stable Isotopes
Figure I.1 New Period Table of Elements showing isotope abundance ranges.
Chapter I.3: Chemically Identical and Yet Not the Same
Figure I.2 δ2 H and δ13 C values of beet sugar and cane sugar of different geographic origin.
Chapter I.5: Stable Isotopic Distribution and Isotopic Fractionation of Light Elements in Nature?
Figure I.3 Schematic representation of changing δ2 H and δ18 O-values of meteoric water as a result of repeated fractional precipitation.
Figure I.4 δ2 H and δ18 O values of whole wood and plant sugars (beet as well as cane sugar) in the framework of the global meteoric water line (GMWL).
Figure I.5 Correlation plot of δ18 O values versus δ2 H values of fruit water pressed from fresh raspberries grown in Spain and in Scotland. Error bars are ± 1 σ. Solid trend line is based on least squares regression while the hashed trend lines is based on orthogonal regression.
Figure I.6 Correlation plot of true, H-exchange corrected δ2 HVSMOW values and δ18 OVSMOW values of raw cotton from eight different countries. Error bars are ± 1 σ. Trend line is δ2 H = 3.83 δ18 O – 133.13.
Figure I.7 Bivariate graph plotting δ15 N versus δ13 C-values of scalp hair samples volunteered by residents in different countries reflecting their regionally different diet. Error bars are ± 1 σ of groups comprising 4 to 10 individuals per region.
Figure I.8 13 C isotopic composition of selected fruit, meat, fish and vegetables. Please note, human collagen and human hair δ13 C-values included here are typical for people with a terrestrial C3 -plant dominated diet.
Figure I.9 15 N isotopic composition isotopic composition of selected fruit, meat, fish and vegetables. Please, note, δ15 N values of fruit and vegetable are not fixed constants but vary depending on farming practice and type of fertilizer usage.
Figure I.10 Simplified schematic representation of typical δ15 N-values for proteinogenous tissue of terrestrial mammals in relation to their trophic level in the food web.
Figure I.11 Global δ2 H isoscape of 2 H abundance in annual precipitation.
Figure I.12 Isoscapes of 2 H (left) and 18 O abundance (right) in freshwater lakes and reservoirs in Scotland. Red dots mark sampling locations. X and Y axes are degrees Longitude West and degrees Latitude North.
Figure I.13 δ2 H isoscape of 2 H abundance in annual precipitation of 2009 in New Zealand.
Figure I.14 Global δ13 C isoscape of mean annual 13 C abundance in plant carbon of terrestrial vegetation.
Chapter I.6: Stable Isotope Forensics in Everyday Life
Figure I.15 Natural variation in 13 C isotopic composition of single seed vegetable oils and selected fatty acids isolated from these oils.
Figure I.16 Dendrogram of 11 pumpkin seed oils obtained from Hierarchical Cluster Analysis of a multivariate data set comprised of 2 H, 13 C and 18 O abundance values and concentration values of 17 trace elements.
Figure I.17 Bivariate plot of δ2 H and δ18 O values of authentic Scottish whisky samples as well as whisky samples known or suspected to be counterfeit;
Figure I.18 An isotopic bivariate plot of δ13 C and δ15 N-values of the API Folic Acid from three different manufacturers at three different locations; mean ±1 σ of each cluster is shown in the middle of the cluster.
Figure I.19 An isotopic bivariate plot of δ13 C and δ18 O-values of the API Naproxen from six different manufacturers (Mfr A to F) in four different countries.
Figure I.20 Principal Component Plot from a principal component analysis of 2 H, 13 C, 15 N and 18 O abundance data of sildenafil citrate tablets from different manufacturers with first and second component explaining 48 % and 39 % respectively of all variability in the data. The large ellipse represents the 95 % confidence interval based on Hotelling's T2 .
Figure I.21 2 H and 18 O abundance data of sildenafil citrate tablets from different manufacturers including genuine Pfizer Viagra® (dashed circle).
Figure I.22 Bivariate plot of corresponding δ2 H and δ13 C values of fatty alcohols showing differentiation according to source.
Chapter II.1: Mass Spectrometry versus Isotope Ratio Mass Spectrometry
Figure II.1 Schematic (top) and photograph (bottom) of a modern IRMS magnetic sector instrument with multi-collector analyser. IS, ion source; EM, electro-magnet, FCC: Faraday cup collectors.
Figure II.2 Graphical representation of isotopic linearity and shot noise envelope for a typical IRMS instrument. Dashed lines at ±0.06 ‰ represent linearity acceptance criterion for 13 C. Δδ = δaccepted − δmeasured .
Chapter II.2: Instrumentation for Stable Isotope Analysis
Figure II.3 Schematic (top) and photograph (bottom) of a typical continuous-flow elemental analyser–isotope ratio mass spectrometer system (EA-IRMS).
Figure II.4 Schematic (top) and photograph (bottom) of a continuous-flow high-temperature conversion/elemental analyser–isotope ratio mass spectrometer system (HTC/EA-IRMS).
Figure II.5 Schematic (top) and photograph (bottom) of a gas chromatography/combustion interface IRMS system (GC/C-IRMS).
Figure II.6 Schematic (top) and photograph (bottom) of a GC(MS)-IRMS hybrid system based on the author's original design, showing from left to right MS, GC with conversion reactor unit and autosampler, the interface unit to the IRMS, and the IRMS.
Chapter II.3: Quality Control and Quality Assurance in Continuous-Flow Isotope Ratio Mass Spectrometry
Figure II.7 Scale normalization equations and linear regression lines obtained from contemporaneously analysed reference materials VMSOW, SLAP2 (solid line) or IAEA-CH-7 and IA-R002 (dashed line) based on data presented in Table II.4.
Figure II.8 Scale normalization equations and linear regression lines obtained from contemporaneously analysed reference materials IAEA-CH-7 and IAEA-CH-6 (solid line) or IAEA-CH-7 and NBS 22 (dashed line) based on data presented in Table II.6.
Chapter II.4: Points of Note for Stable Isotope Analysis
Figure II.9 A Costech Zero-Blank autosampler as used in our laboratory for bulk stable isotope analysis by EA- or HTC/EA-IRMS. The 1/16′′ tubing above the isolation valve delivers helium to the autosampler tray while the 1/16′′ tubing below delivers helium to the conversion reactor.
Figure II.10 Effect of Argon (Ar) concurrently present with CO2 in the ion source on measured δ13 C values of same sized aliquots of CO2 (accepted δ13 CVPDB = −32.56 ‰).
Figure II.11 Illustration of the potential interference on isotope ratio measurement of an H2 peak caused by partial overlap with a following N2 peak.
Figure II.12 Comparison of peak heights, peak shape and retention time of an H2 peak in the absence (left) and the presence (right) of a partially overlapping N2 peak.
Figure II.13 Top: Untreated ammonium nitrate from six different sources. Note the already “wet” appearance of the sample in the top right corner. Bottom: The same samples after an 8-day exposure to ambient atmosphere.
Figure II.14 Part of a cellulose sheet showing grey circles around some of the non-exchangeable hydrogen fixed by hydrogen bridge bonding while black circles are drawn around hydrogen atoms prone to exchange.
Figure II.15 Part of a protein chain illustrating how intra-molecular hydrogen bridging bonds between peptide bonds maintain (or fix) an α-helical structure. A grey ellipse is drawn around the hydrogen bridging bond to indicate the non-exchangeable nature of the hydrogen atoms locked up in this bond.
Figure II.16 Part of a β-keratin sheet showing how intra-molecular hydrogen bridging bonds between peptide bonds maintain (or fix) a β-sheet structure. Grey ellipses are drawn around some of the hydrogen bridging bonds to indicate the non-exchangeable nature of the hydrogen atoms locked up in these bonds.
Figure II.17 Consistent longitudinal values of hydrogen exchange corrected true δ2 H values of human hair (circles and diamonds) determined as a result of contemporaneous two-stage equilibration and therefore IT principle based measurement of total hydrogen δ2 H values (squares).
Figure II.18 Comparability of non-exchangeable true δ2 Hhair values for four stock hair samples determined by two-point exchange equilibration methods as implemented by three laboratories located in Canada (O), USA (U) and the UK (S).
Figure II.19 Correction by comparative equilibration based on linear regression analysis of measured/true δ2 H values for β-keratin standards Cow Hoof (CHK) and Bowhead Whale Baleen (BWB-II) (diamonds) with β-keratin standard Chicken Feather (CFK) (square) serving as quality control.
Figure II.20 Illustration of the time displacement between 13 CO2 (m/z 45) and 12 CO2 (m/z 44) peaks of a compound CO2 peak due to the “inverse” chromatographic isotope effect. Note the S-shaped 45/44 ratio trace as a result of the 13 CO2 peak (m/z 45 signal) preceding the 12 CO2 peak (m/z 44 signal). The line marks indicate start, centre (apex), and end of the peak/s. Overall peak width of the compound CO2 peak at baseline is 19 s.
Chapter II.5: Statistical Analysis of Stable Isotope Data within a Forensic Context
Figure II.21 Trivariate plots of measured δ13 C, δ2 H and δ15 N values of 10 Ecstasy tablets from eight different seizures in two different European countries. A circle is drawn around the data points of tablets from the same seizure.
Figure II.22 HCA using δ2 H, δ13 C, δ15 N and δ18 O values as well as MDMA content from 10 Ecstasy tablets from eight different seizures in two different European countries (furthest neighbour, Euclidean distance). Cases 2, 3 and 4 are Ecstasy tablets from the same seizure.
Figure II.23 Plot of PCA score factors for the first two principal components of multivariate data from farmed and wild European sea bass.
Figure II.24 The means of δ2 H, δ13 C and δ18 O observations for each of the 51 white paint samples plotted over the smoothed bivariate density (darker colour equates to higher density) for each variate pair. The items are represented as ellipses corresponding to 95 % of the empirical distribution for that item.
Appendix II.A: How to Set Up a Laboratory for Continuous-Flow Isotope Ratio Mass Spectrometry
Figure II.A.1 Pressure-triggered change-over unit for helium supply.
Figure II.A.2 Laboratory gas delivery manifold fed from external gas supply.
Chapter III.2: Distinguishing Drugs
Figure III.1 Morphine and diacetylmorphine a.k.a. heroin.
Figure III.2 Cocaine.
Figure III.3 Cocaine δ 2 H (a) and δ 15 N (b) isoscapes of Colombia based on 336 authentic samples prepared from coca leafs.
Figure III.4 Six amphetamine powders from the 18 seizures isotopically profiled in Figure III.5.
Figure III.5 Bivariate isotope profile plot of δ 15 N and corresponding δ 13 C values for 18 amphetamine samples seized from 6 different individuals.
Figure III.6 Schematic of synthetic routes “Emde”, “Nagai”, “Moscow” and “Hypo” for preparing methamphetamine from ephedrine or pseudoephedrine.
Figure III.7 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values of six methamphetamine batches per synthetic route each, synthesized from aliquots of the same precursor. Arrows and isotopic fractionation factors refer to the centroid positions of all batches per synthetic route.
Figure III.8 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values of six methamphetamine batches per synthetic route each, synthesized from aliquots of pseudo -ephedrine extracted from Sudafed™ tablets using methylated spirits (DIY store brand). Arrows and isotopic fractionation factors refer to the centroid positions of all batches per synthetic route.
Figure III.9 Schematic synthetic route for PMK from safrole.
Figure III.10 Schematic synthetic routes for MDMA from PMK.
Figure III.11 Bivariate isotope profile plot of δ 15 N and corresponding δ 13 C values of six MDMA batches each per synthetic route with three different synthetic routes being studied.
Figure III.12 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values of six MDMA batches each per synthetic route with three different synthetic routes being studied.
Figure III.13 Dendrogram resulting from HCA of 18 batches of MDMA; three variables; Euclidean distance, single linkage. Cases 1–6, 7–12 and 13–18 refer to synthetic routes Al/Hg amalgam, NaBH4 and Pt/H2 respectively.
Figure III.14 Bivariate plot of δ 2 H and corresponding δ 13 C values of MDMA*HCl batches from controlled (recipe “a”), centre-point (recipe “b”) and factorial design synthetic routes.
Figure III.15 Bivariate plot of δ 15 N and corresponding δ 13 C values of MDMA*HCl batches from controlled (recipe “a”), centre-point (recipe “b”) and factorial design synthetic routes.
Figure III.16 PCA scores plot for the first two principal components (PC1, PC2) using both IRMS and GC–MS data (Van Deursen normalized to the sum of the targets; pre-treated with the fourth root method) for all synthesized MDMA*HCl samples permitting discrimination by laboratory product: ( ) Al/Hg amalgam; ( ) NaBH4 ; ( ) Pt/H2 recipe “a”; ( ) Pt/H2 recipe “b”; ( ) Pt/H2 factorial design batches.
Figure III.17 Schematic synthetic route for 4′-methylmethcathinone (4-MMC) from 4′-methylpropiophenone.
Figure III.18 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values of six batches of 4-MMC, synthesized from aliquots of the same precursor #S.
Figure III.19 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values of six batches of 4-MMC, synthesized from aliquots of the same precursor #A.
Figure III.20 Schematic synthetic route for benzylpiperazine*HCl (BZP*HCl) from piperazine hexahydrate (PH) and piperazine dihydrochloride (PD) via intermediate piperazine*HCl.
Figure III.21 Bivariate isotope profile plot of average δ 15 N and corresponding mean δ 13 C values of six batches of BZP*HCl, synthesized from aliquots of chemically identical precursors PH and PD sourced from three different suppliers AA, MP and SA.
Figure III.22 Bivariate isotope profile plot of δ 15 N and corresponding δ 13 C values of 21 designer drug tablets containing both BZP and TMFPP, seized by police on two separate occasions.
Figure III.23 Bivariate isotope profile plot of δ 2 H and corresponding δ 15 N values of 21 benzocaine control samples as analysed by two stable isotope laboratories in Australia and the UK. Error bars represent overall measurement uncertainty at 95% confidence level.
Figure III.24 PCA scores plot for principal components t(1) and t(2) of a multivariate stable isotope dataset of the benzocaine samples of various seizures from two Operations F and P run by two different UK law enforcement agencies. The first principal component accounts for 83.1% of all the variability in the data. The large ellipse represents the 95% confidence interval based on Hotelling's T 2 . The smaller ellipses are indicative of groupings obtained from HCA of the same dataset.
Chapter III.3: Elucidating Explosives
Figure III.25 Bivariate isotope profile plot of δ 15 N and corresponding δ 18 O values of ammonium nitrate prills (n = 41) from various sources with either country of origin or manufacturer shown where known. Error bars are ±1 σ. Ellipses represent groupings obtained from HCA.
Figure III.26 Ammonium nitrate prills from various sources. Image provided courtesy of Dr Sarah Benson (Forensic Operations Laboratory, Australian Federal Police, Canberra).
Figure III.27 Detailed bivariate isotope profile plot of δ 15 N and corresponding δ 13 C values for the explosive RDX from two different sources demonstrating homogeneity of the samples and repeatability of stable isotope analysis (N = 18). Figure is based on data generated by or for my then PhD student Claire Lock.
Figure III.28 Three-dimensional plot of corresponding δ 2 H, δ 15 N and δ 13 C values for the RDX precursor hexamine. The encircled two data points are samples HEX#G and HEX#N from two different bottles of the same batch from the same supplier. Figure is based on data generated by or for my then PhD student Claire Lock.
Figure III.29 Dendrogram of a HCA (single linkage, Euclidean distance) of the trivariate stable isotope data set of 15 hexamine samples examined. Figure is based on data generated by or for my then PhD student Claire Lock.
Figure III.30 Schematic synthetic route for RDX and HMX from hexamine.
Figure III.31 Bivariate plot of δ 15 N and corresponding δ 13 C values of six batches of RDX, synthesized from hexamine from five different sources using the Woolwich process.
Figure III.32 Chemical structures of HMTD and TATP.
Figure III.33 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values of TATP made from acetone from different sources.
Figure III.34 Schematic of the first five reaction steps of TATP synthesis involving the enol form of acetone as starting point of the reaction thus explaining the introduction of an alien hydrogen (shown in boldface) into the molecule.
Figure III.35 Correlation plot of δ 18 O of hydrogen peroxide solutions and corresponding δ 18 O values of TATP.
Figure III.36 Correlation plot of δ 18 O of hydrogen peroxide solutions and corresponding δ 18 O values of HMTD.
Figure III.37 Changing δ 2 H values of a 60% hydrogen peroxide solution with increasing dilution. Figure is based on data generated by or for my then PhD student Claire Lock.
Figure III.38 Changing δ 18 O values of a 60% hydrogen peroxide solution with increasing dilution. Figure is based on data generated by or for my then PhD student Claire Lock.
Figure III.39 Mixing curve showing δ 18 O values calculated for samples of flour/hydrogen peroxide mixtures composed of decreasing amount of flour and increasing amount of H2 O2 (0 % mark = 100% flour and no H2 O2 ; 100% mark = no flour and 100% H2 O2 at a concentration of 70% w/w). This mixing curve is based on δ 18 OVSMOW values of +25 ‰ and +12 ‰ for flour and H2 O2 respectively.
Figure III.40 Mixing curve showing δ 18 OVSMOW values calculated for samples of flour/hydrogen peroxide mixtures composed of a constant amount of flour and increasing amounts of H2 O2 (0% no H2 O2 ; 100% mark: flour : H2 O2 = 50 : 50; 200% mark: flour : H2 O2 = 33.3 : 66.7). This mixing curve is based on δ 18 OVSMOW values of +25 and +12 ‰ for flour and hydrogen peroxide respectively.
Chapter III.4: Matching Matchsticks
Figure III.41 Schematic of a series of reactions that may result in a change of 18 O abundance in oxygen bound as carbonyl (C=O) group. Note that in a living organism the steps involving H+ transfer for example would require NADH+H+ /NADH.
Figure III.42 Bivariate isotope profile plot of δ 2 H and corresponding δ 13 C values from matchsticks recovered at the crime scene, matchsticks seized from the suspect's house and matchsticks collected to serve as controls.
Figure III.43 Examination by microscopy of the thin sections of matches secured at the crime scene and seized from the suspects house confirms conclusion drawn from stable isotope analysis presented in Figure III.35.
Chapter III.5: Provenancing People
Figure III.44 You are what and where you eat and drink – the presence of stable isotopes of light elements in the human body.
Figure III.45 Different human tissues provide different chronological stable isotopic records and thus different levels of information about a person's life history or life trajectory prior to death.
Figure III.46 Correlation between δ 2 H values of human scalp hair and δ 2 H values of source water for populations whose diet is sourced regionally (non-globalised; dashed line), country-wide (solid lines) or almost globalised (here: North America-wide; dot-dashed line).
Figure III.47 Bivariate plot of corresponding δ 15 N and δ 13 C values in human scalp hair from people with different geographical, ethnic and cultural backgrounds.
Figure III.48 Comparison of matching scalp hair and nail δ 13 C values from 93 volunteers living in 31 countries illustrating the trend for nail δ 13 C values to be slightly more negative than their corresponding hair δ 13 C values (dashed line). The solid line represents the line of δ 13 C (hair) = δ 13 C (nail).
Figure III.49 Global distribution of 13 C in human scalp hair.
Figure III.50 Comparison of matching scalp hair and nail δ 15 N values from 93 volunteers living in 31 countries illustrating the trend for nail δ 15 N values to be more positive than their corresponding hair δ 15 N values (dashed line). The solid line represents the line of δ 15 N (hair) = δ 15 N (nail).
Figure III.51 Equilibrium reactions of CO2 /[CO3 2− ] with and in water that may result in a change of 18 O abundance in oxygen bound in carbon dioxide.
Figure III.52 (a) δ 18 O isoscape of 18 O abundance in tap water the contiguous USA. (b) δ 18 O isoscape of 18 O abundance in carbonate of tooth enamel throughout the USA.
Figure III.53 Correlation graphs according to Daux et al . (2008), Longinelli (1984) and Luz and Kolodny (1985) for δ 18 Ophosphate v. δ 18 Owater and the resulting range of calculated δ 18 Owater for the same δ 18 Ophosphate .
Figure III.54 Correlation graph for δ 18 Ophosphate values of tooth enamel, calculated from measured δ 18 Ocarbonate values, versus corresponding δ 18 Owater values taken from the OIPC for the volunteers' known locations.
Figure III.55 Approximate δ 13 C values for 13 C isotopic composition of various body pools and tissue. Please, note, all human tissue δ 13 C-values shown here are based on a terrestrial C3 -plant dominated diet of an omnivore.
Figure III.56 13 C isotopic composition of various food, animal and human tissue. Please note that human collagen and human hair δ 13 C values shown here are typical for people with a terrestrial C3 plant-dominated diet.
Figure III.57 Simplified schematic representation of corresponding δ 13 C/δ 15 N values typically observed for human scalp hair in relation to a person's diet and trophic level or health status.
Figure III.58 Bivariate graph plotting δ 15 N against corresponding δ 13 C values from scalp hair of a vegan and scalp hair of an omnivore whose staple diet is comprised to a large extent of fish and meat.
Figure III.59 Diagram of the area of skull submitted for stable isotope analysis (shaded in black).
Figure III.60 Sample of scalp hair as submitted for sequential stable isotope analysis.
Figure III.61 Time-resolved changes in 15 N composition of the victim's scalp hair. Long dashed lines indicate periods of stable nutritional status while dot-dashed line indicate periods of nutritional stress that were interpreted to result from (enforced) crash diets to facilitate clandestine transfer across borders.
Figure III.62 Time-resolved changes in 2 H composition of the victim's scalp hair.
Figure III.63 Tentative geographic life history for the last 17 months prior to death as gleaned from 2 H analysis of scalp hair segments from the skull found in 2001 at Minerals Road, Conception Bay South, Newfoundland.
Figure III.64 Poster based on information derived from, amongst other sources, stable isotope analysis for an appeal to the public for information regarding the murder victim found at Minerals Road, Conceptions Bay South, Newfoundland.
Figure III.65 Geographic life trajectory of the murder victim found in the Dublin Royal Canal (ROI, Republic of Ireland) based on 18 O analysis of bone phosphate extracted from a piece of femur.
Figure III.66 Chronology of changing diet δ 13 C and tissue δ 15 N values falling into three distinct periods I, II and III during the last 12 months in the life of a 5-year-old child.
Figure III.67 Schematic chronology of a murder victim's geographic movement showing six periods of residency in four different regions during the last two years of her life. Modelled source water δ 18 O values are based on measured hair δ 18 O values.
Figure III.68 Chronological dietary life history obtained from five different tissue of the murder victim found in Eastern Germany with samples from left to right moving from the most distant to the most recent time period; δ -values of collagen are tissue shift adjusted to bring them line with hair δ -values.
Figure III.69 Global map with highlighted areas of model δ 18 O predictions for precipitation δ 18 O values ranging from −10.1 ‰ to −7.6 ‰ illustrating the constraining power of stable isotope profiling in aid of human provenancing.
Figure III.70 Zoomed-in version of the global map shown in Figure III.69 focusing on Central Europe and the United Kingdom.
Chapter III.6: Stable Isotope Forensics of Other Physical Evidence
Figure III.71 Correlation plot of total δ 2 H values and corresponding δ 18 O values for seven batches of natural spun cotton yarn made from cotton grown in Argentina (AR), Egypt (EG), Turkey (TR) and Uzbekistan (Uzb). Light circles are centroids of individual analyses (dark circles).
Figure III.72 Intra-ream variability in 13 C and 18 O composition of five different brands of office paper; six samples per ream were collected and each sample was analysed in replicates of eight.
Figure III.73 Inter-ream variability in 13 C and 18 O composition of four different brands of office paper; seven reams per brand were sampled and samples from each ream were analysed in replicates of seven at least.
Figure III.74 Bivariate plot of δ 2 H and corresponding δ 13 C values of intact (untreated) brown parcel tape samples.
Figure III.75 Bivariate plot of δ 2 H and corresponding δ 13 C values of treated brown parcel tape samples, i.e. backing material only.
List of Tables
Chapter I.1: What are Stable Isotopes?
Table I.1 Key figures for stable isotopes of light elements
Chapter I.2: Natural Abundance Variation of Stable Isotopes
Table I.2 Scale reference points and their defining scale anchors for stable isotopes of light elements
Table I.3 A representative but not exhaustive list of international reference materials for stable isotope ratio mass spectrometry together with their stable isotope abundance values as published by the Commission on Isotopic Abundances and Atomic Weights (CIAAW; http://www.ciaaw.org/reference-materials.htm)
Chapter I.3: Chemically Identical and Yet Not the Same
Table I.4 Select examples of 13 C and 2 H abundance values of sugar from different plant sources and of different geographic origin
Table I.5 Influence of isotopic composition on physical properties of H2 O and its isotopologues
Chapter I.6: Stable Isotope Forensics in Everyday Life
Table I.6 Impact of using reference materials (RM) other than VSMOW (RM1) and SLAP (RM2) on δ 18 O values calculated using equation I.16
Chapter II.1: Mass Spectrometry versus Isotope Ratio Mass Spectrometry
Table II.1 Comparison of MS and IRMS systems when applied to stable isotope analysis at near natural abundance level
Chapter II.2: Instrumentation for Stable Isotope Analysis
Table II.2 Key dates in instrument research and development influencing design and evolution of commercially available CF-IRMS systems
Chapter II.3: Quality Control and Quality Assurance in Continuous-Flow Isotope Ratio Mass Spectrometry
Table II.3 Example of the day-to-day variability of measured δ values for international reference materials USGS40, USGS41, IAEA-601, IAEA-602, VSMOW and SLAP2, and resulting differences for stretch factor s and off-set b in corresponding scale normalization equations
Table II.4 Sample scale normalization to VSMOW/SLAP; δ2 H values rounded to 2 decimal places
Table II.5 Two end-member δ2 H scale normalization to VSMOW showing the effect of appropriate [a] and inappropriate [b] choice of scale anchors (shown in bold face)
Table II.6 Organic 13 C reference materialsa
Table II.7 Two-end-member VPDB δ13 C scale normalization examples showing the effect of appropriate (a) and inappropriate (b) choice of scale anchors (shown in bold face). All δ13 C values are given as ‰ values
Chapter II.4: Points of Note for Stable Isotope Analysis
Table II.8 List of new reference materials for BSIA and CSIAa (Schimmelmann et al. , 2016)
Table II.9 Generic batch sequence composition in BSIA favouring high sample throughput under stable experimental conditions using 2 H isotope analysis as example
Table II.10 Influence of reactor set-up on accuracy of δ2 H measurement of caffeine and human hair standards of different 2 H compositiona
Table II.11 Relative amino acid abundance as % value of the total number of amino acids per protein unit in human hair (α-keratin), claws or feathers (β-keratin), type I collagen (e.g. bone collagen), casein (bovine milk protein) and honey protein
Table II.12 Total number of H atoms and number of exchangeable H atoms in α-keratin's 16 most abundant amino acids
Table II.13 Calculated and measured molar exchange fraction f E for H of proteins and cellulose
Table II.14 Scale normalized δ2 HVSMOW and δ18 OVSMOW values for matching paired sets of hair samples from different individuals and geographic regionsa
Table II.15 Measured values for the molar H exchange fraction f E and “true” δ2 Hvsmow values of human hair standards USGS42 and USGS43 at different equilibration temperatures
Table II.16 Influence of reactor set-up on δ2 H values of N- and Cl-rich compounds obtained by CSIA and BSIA using different reactor set-upsa
Chapter II.5: Statistical Analysis of Stable Isotope Data within a Forensic Context
Table II.17 List of 51 white architectural paints from different sourcesa
Table II.18 Percentage distributions for the likelihood ratios from each comparisona
Chapter II.6: Quality Control and Quality Assurance in Forensic Stable Isotope Analysis
Table II.19 Comparison of longitudinal CO2 cylinder gas calibration based on averaged Δδ off-sets versus scale normalization. All δ13 C values are given as ‰ values.
Appendix II.A: How to Set Up a Laboratory for Continuous-Flow Isotope Ratio Mass Spectrometry
Table II.A.1 List of useful tools and equipment in an IRMS laboratory
Table II.A.2 List of drying agents in order of their hygroscopic nature and thus efficiency as desiccant
Chapter III.2: Distinguishing Drugs
Table III.1 Drug schedules and drug classes in the US and the UK respectively
Table III.2 Observed ranges for δ 2 H, δ 13 C, δ 15 N and δ 18 O values of natural and semisynthetic drugs
Table III.3 Stable isotope abundance ranges observed in 529 authentic samples of cocaine from 19 known different South American coca-growing regions
Table III.4 Reported δ 2 H, δ 13 C and δ 15 N values of ephedrine *HCl and pseudoephedrine from various sources
Table III.5 δ 2 H values (given as ‰ values) for amphetamines synthesized by the “nitrostyrene” route under controlled conditions and samples seized from a clandestine laboratory
Table III.6 Summary δ 2 H, δ 13 C and δ 15 N values of MDMA hydrochloride samples synthesized from aliquots of the same precursor PMK but by three different synthetic routes of reductive amination
Chapter III.3: Elucidating Explosives
Table III.7 Summary of fractionation factors α and enrichment factors ϵ for individual hexamine/RDX precursor/product pairs
Chapter III.5: Provenancing People
Table III.8 Formation, mineralisation and eruption of selected permanent teeth
Table III.9 Approximate tissue specific stable isotope abundance valuesa in relation to dietary stable isotopic compositiona for a healthy omnivorous human subsisting on a terrestrial, C3 plant dominated diet
Table III.10 Results of stable isotope analysis of the tissue samples studied in the case of the unidentified body found at Minerals Road, Conception Bay South, Newfoundland. Table is based on data generated by Maria Hillier, Dr Vaughan Grimes, and the author as part of this case investigation. Stable isotope abundance values are given as 103 × δ h E
Methods and Forensic Applications of Stable Isotope Analysis
Second Edition
Wolfram Meier-Augenstein
Robert Gordon University
Aberdeen, UK
This edition first published 2018
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Library of Congress Cataloging-in-Publication Data
Names: Meier-Augenstein, Wolfram.
Title: Stable isotope forensics : methods and forensic applications of stable isotope analysis / Professor Dr. Wolfram Meier-Augenstein, Robert Gordon University, Aberdeen, UK.
Description: Second edition. | Hoboken, NJ : Wiley, 2018. | Series: Developments in forensic science | Includes bibliographical references and index. | Description based on print version record and CIP data provided by publisher; resource not viewed.
Identifiers: LCCN 2017010492 (print) | LCCN 2017011764 (ebook) | ISBN 9781119080220 (pdf) | ISBN 9781119080237 (epub) | ISBN 9781119080206 (cloth)
Subjects: LCSH: Chemistry, Forensic. | Stable isotopes.
Classification: LCC RA1057 (ebook) | LCC RA1057 .M45 2018 (print) | DDC 614/.12–dc23
LC record available at https://lccn.loc.gov/2017010492
Cover Design: Wiley
Cover Images: (Background) © chokkicx/Gettyimages;
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The world of forensic science is changing at a very fast pace in terms of the provision of forensic science services, the development of technologies and knowledge and the interpretation of analytical and other data as it is applied within forensic practice. Practicing forensic scientists are constantly striving to deliver the very best for the judicial process and as such need a reliable and robust knowledge base within their diverse disciplines. It is hoped that this book series will provide a resource by which such knowledge can be underpinned for both students and practitioners of forensic science alike.
It is the objective of this book series to provide a valuable resource for forensic science practitioners, educators and others in that regard. The books developed and published within this series come from some of the leading researchers and practitioners in their fields and will provide essential and relevant information to the reader.
Professor Niamh NicDaéid Series Editor
Foreword by Dame Sue Black
I am so delighted to be asked to write the foreword for a text where I understand so little of the background science. A reasonable question might be, then why ask a forensic anthropologist to do this when she barely passed Higher Chemistry and has absolutely no experience in the field of stable isotope analysis? One of the most important aspects of working within a forensic team is to know the limits of one's own ability and to recognize and utilize the strengths of others. It has been my pleasure to work with Wolfram for many years and when forensic casework comes to me, it is without second thought that I pass it on to him knowing that the investigative authorities will not be hoodwinked by a pseudoscientist.
A single-author text in these days is rare and the value of this book lies in the dedication and experience of the author, which is evident in the clarity of prose, the honest illustration of evidence and the realistic practical application of the subject – it makes this a text of genuine scientific value. That a second edition has been requested is a clear indication that the field is still progressing and that new research is still being reported. In the current world of forensic science flux, it is vital that robust scientific research endeavours continue and that it be reported not only in published peer-reviewed papers but collocated in scholarly tomes for easy reference.
In my early discussions with Wolfram I admit to having been a bit of a sceptic, but over time I have been educated and fully persuaded of the value of stable isotope analysis to the world of provenancing and human identification. There have been several instances where conclusions drawn regarding ethnic origin based on forensic anthropological examination of skeletal remains were corroborated independently by results from stable isotope analysis of bone and teeth. One need only read the case histories included in the text to appreciate the practical value of this approach to forensic investigations and, in particular, when attempting to establish the identity of the deceased, which is a pivotal component of any successful investigation.
For me, one of the most important and reassuring aspects of this text is its brutal openness, honesty and transparency. Without apology it identifies equally where are the strengths and limitations of the science and its interpretation for forensic purposes. Whilst this book will challenge those who are not chemically literate, it will quickly become established as the “go-to” text for all practitioners and end users who require to have a firm grasp of the complexities of the subject if its relevance is to be fully understood as a part of intelligence-based investigation.
Prof. Dame Sue Black, PhD, DBE, OBE, FRSE Leverhulme Research Centre for Forensic Science University of Dundee, UK
Foreword by Commissioner Mark Harrison
As an early adopter in applying stable isotope forensic techniques to aid my own criminal investigations, I have followed closely its further development and I am honoured to write the foreword for this second edition of Stable Isotope Forensics by Dr Meier-Augenstein.
Since Dr Meier-Augenstein's first edition of this textbook, crime, through globalization has become more transnational requiring law enforcement to operate in a criminal environment where uncertainty and complexity are increasing and their time to respond is decreasing. Forensic science's response to these challenges has seen the expansion of its contribution beyond prosecution and more to aid investigators in the disruption of crime.
This changing emphasis by law enforcement to one of disrupting organized crime and terrorism is enabling stable isotope forensics (SIF) to increase its value to investigators whereby its contribution to casework is both evidential and in the provision of forensic intelligence.
Criminal syndicates are increasingly interconnected and often commodity based and it is here that SIF profiling is adding value in diverse areas such as narcotics, human trafficking and environmental crime, where provenance is an investigative priority enabling the mapping of criminal networks and the source and transit countries they use. Further SIF innovation has been seen in recent times through countries testing the waste water in their cities and towns to gain greater understanding of the geographic and demographic profiles of drug use, bringing together law enforcement and health agencies in harm reduction programs.
Since the first edition of this book, terrorist groups have become less formalized and radicalization affects all societies through the interconnected world of the Internet. The online-inspired foreign fighter phenomenon has enabled opportunities for SIF profiles to provide significant forensic intelligence value to law enforcement in provenancing the origin of these terrorists and their movements throughout the world.
The scope of SIF contribution is expanding and is only currently limited due to the provision of reference databases. The next decade will see increasing convergences with other techniques such as DNA phenotyping to provide a more holistic picture of criminal identity. Big data challenges will also be addressed to enable timely processing of samples for both evidentiary and forensic intelligence purposes to rapidly answer the who, what, where and how that are, and will continue to be the key drivers of all criminal investigations.
Commissioner Mark Harrison, MBE Head of Criminal Intelligence, Australian Federal Police
Foreword to the 1st Edition
I am delighted to be able to write the foreword for this, the first textbook on stable isotope forensics.
The coverage is wide, ranging from fundamentals to policy issues, and therefore this text will be of benefit to practitioners, researchers and investigators, indeed to anyone who has an interest in this new forensic discipline.
The year 2001 saw the formation of the Forensic Isotope Ratio Mass Spectrometry (FIRMS) Network. Since then much has been achieved in terms of advancing the forensic application of stable isotope analysis, this textbook being the latest significant step.