Stable Isotope Forensics: Methods and Forensic Applications of Stable Isotope Analysis

The number–one guide, internationally, to all aspects of forensic isotope analysis, thoroughly updated and revised and featuring many new case studies

This edition of the internationally acclaimed guide to forensic stable isotope analysis uses real–world examples to bridge discussions of the basic science, instrumentation and analytical techniques underlying forensic isotope profiling and its various technical applications. Case studies describe an array of applications, many of which were developed by the author himself. They include cases in which isotope profiling was used in murder, and drugs–related crime investigations, as well as for pharmaceutical and food authenticity control studies.

Updated with coverage of exciting advances occurring in the field since the publication of the 1st edition, this 2nd edition explores innovative new techniques and applications in forensic isotope profiling, as well as key findings from original research. More than a simple update, though, this edition has been significantly revised in order to address serious problems that can arise from non–comparable and unfit–for–purpose stable isotope data. To that end, Part II has been virtually rewritten with greater emphasis now being placed on important quality control issues in stable isotope analysis in general and forensic stable isotope analysis in particular.

Written in a highly accessible style that will appeal to practitioners, researchers and students alike Illustrates the many strengths and potential pitfalls of forensic stable isotope analysis Uses recent case examples to bridge underlying principles with technical applications Presents hands–on applications that let experienced researchers and forensic practitioners match problems with success stories    Includes new chapters devoted to aspects of quality control and quality assurance, including scale normalisation, the identical treatment principle, hydrogen exchange and accreditation

Stable Isotope Forensics, 2nd Edition is an important professional resource for forensic scientists, law enforcement officials, public prosecutors, defence attorneys, forensic anthropologists and others for whom isotope profiling has become an indispensable tool of the trade. It is also an excellent introduction to the field for senior undergraduate and graduate forensic science students.

"All students of forensic criminology, and all law enforcement officers responsible for the investigation of serious crime , will want to study this book. Wolfram highlights the value, and future potential, of Stable Isotope Forensics as an emerging powerful tool in the investigation of crime."

Roy McComb, Deputy Director, Specialist Investigations, National Crime Agency (NCA), UK

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.

Prof Dame Sue Black, PhD, DBE, OBE, FRSE, Leverhulme Research Centre for Forensic Science, University of Dundee, UK

Table of Contents

Foreword to 2nd edition by Prof. Dame Sue Black, DBE, OBE, FRSE

Foreword to 2nd edition by Commissioner Mark Harrison, MBE

Foreword to 1st edition by Sean Doyle

Book endorsement

Preface by the author

List of Abbreviations

Introduction: Stable Isotope Profiling or Chemical DNA : A New Dawn for Forensic Chemistry?

Part I: How it works

I.1 What are Stable Isotopes?

I.2 Natural Abundance Variation of Stable Isotopes

I.3 Chemically Identical and Yet Not the Same

I.4 Isotope Effects, Mass Discrimination and Isotopic Fractionation

I.4.1 Physical Chemistry Background

I.4.2 Fractionation Factor Ñ and Enrichment Factor Õ

I.4.3 Isotopic Fractionation in Rayleigh Processes

I.4.4 Isotopic Fractionation Summary

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 Sulphur

I.5.6 Isoscapes

I.6 Stable Isotope Forensics in Everyday Life

I.6.1 Food Forensics

I.6.1.1 Authenticity and Provenance of Single–Seed Vegetable Oils

I.6.1.2 Authenticity and Provenance of Beverages

I.6.1.3 Caveats

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

I.7 Summary of Part I

References Part I

Part II: Instrumentation, Analytical Techniques and Data Quality

II.1 Mass Spectrometry versus Isotope Ratio Mass Spectrometry

II.1.1 Stability and Isotopic Linearity

II.2 Instrumentation and Ô Notation

II.2.1 Dual–Inlet Isotope Ratio Mass Spectrometry

II.2.2 Continuous Flow Isotope Ratio Mass Spectrometry

II.2.3 Bulk Material Stable Isotope Analysis

II.2.3.1 13C, 15N and 34S

II.2.3.2 2H and 18O

II.2.4 Compound Specific Stable Isotope Analysis of Volatile Organic Compounds

II.2.4.1 Compound Specific 13C or 15N Analysis by GC/C–IRMS

II.2.4.2 Compound Specific 2H or 18O Analysis by GC/HTC–IRMS

II.2.4.3 Position–Specific Isotope Analysis

II.2.5 Compound Specific 13C Analysis of Polar, Non–Volatile Organic Compounds

II.2.6 Compound Specific Stable Isotope Analysis and Forensic Compound Identification

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 Principle of Identical Treatment

II.3.3 The Importance of Scale Normalisation

II.3.3.1 Scale Normalisation of Measured Ô2H Values to VSMOW

II.3.3.2 Scale Normalisation of Measured Ô13C Values to VPDB

II.3.3.3 Scale Normalisation of Measured Ô18O Values to VSMOW

II.3.3.4 Scale Normalisation of Measured Ô15N Values to AIR

II.3.3.5 Scale Normalisation of Measured Ô34S Values to VCDT

II.4 Points of Note for Stable Isotope Analysis

II.4.1 Preparing for Analysis

II.4.2 Generic Considerations for BSIA

II.4.2.1 Scale Normalisation

II.4.2.2 Keeping Your Powder Dry

II.4.2.3 Isobaric Interference

II.4.2.4 Ionization Quench Effect

II.4.3 Particular Considerations for BSIA

II.4.3.1 Bulk 15N Analysis of Nitrates

II.4.3.2 Bulk 2H Analysis of Nitrogen Rich Compounds

II.4.3.3 Total Ô2H versus True Ô2H Values

II.4.3.4 Compounds with Exchangeable Hydrogen and Implications for 2H Abundance Analysis

II.4.3.4.1 Chemical and Biochemical Considerations – Example: Hair

II.4.3.5 2H Analysis of Human Hair

II.4.3.5.1 Two–point Equilibration with Water

II.4.3.5.2 Two–point End–member Comparative Equilibration

II.4.3.5.3 On–line Two–point End–member Comparative Steam Equilibration

II.4.4 Points of Note for CSIA

II.4.4.1 Scale Normalisation

II.4.4.2 Isotope Effects in GC–IRMS during Sample Injection

II.4.4.3 The Chromatographic Isotope Effect in GC–IRMS

II.4.4.4 Derivatisation of Polar Compounds for GC–IRMS

II.4.4.5 Compound Specific 2H Analysis of N or Cl Rich Compounds

II.5 Statistical Analysis of Stable Isotope Data within a Forensic Context

II.5.1 Chemometric Analysis

II.5.2 Bayesian Analysis

II.6 Quality Control and Quality Assurance in Forensic Stable Isotope Analysis

II.6.1 Accreditation to ISO/IEC 17025:2005

II.6.1.1 Who Assesses the Assessors?

II.6.2 The Forensic Isotope Ratio Mass Spectrometry Network (FIRMS)

II.7 Summary of Part II

Appendix II.A: Guidelines for Setting up a Laboratory for Continuous–Flow IRMS

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: Sample Preparation Protocols

II.C.1 Derivatisation of Amino Acids for Compound Specific Isotope Analysis by GC–IRMS

II.C.2 Acid Digest of Carbonate from Bio–apatite for 13C and 18O Analysis

II.C.3 Preparing Silver Phosphate from Bio–apatite for 18O Analysis

II.C.4 Two–stage Equilibration Protocol for Determination of non–ex Ô2H 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

III.1 Forensic Context

III.1.1 Legal Context

III.2 Distinguishing Drugs

III.2.1 Natural and Semi–synthetic Drugs

III.2.1.1 Marijuana

III.2.1.2 Morphine and Heroin

III.2.1.3 Cocaine

III.2.2 Synthetic Drugs

III.2.2.1 Amphetamine

III.2.2.2 Methamphetamine: Synthesis and Isotopic Signature

III.2.2.2.1 Two Different Synthetic Routes  Clandestine Conditions.

III.2.2.3 MDMA: Synthesis and Isotopic Signature

III.2.2.3.1 Three Different Synthetic Routes Controlled Conditions.

III.2.2.3.2 One Synthetic Route Variable Conditions

III.2.3 "Legal Highs" and "Designer Drugs"

III.2.3.1 Mephedrone

III.2.3.2 Piperazines

III.2.4 Excipients

III.2.5 Conclusions

III.3 Elucidating Explosives

III.3.1 Bulk Isotope Analysis of Explosives and Precursors

III.3.1.1 Ammonium Nitrate

III.3.1.2 Hexamine, RDX, C4 and Semtex

III.3.1.3 Isotopic Product/Precursor Relationship

III.3.1.3.1 RDX and HMX

III.3.1.3.2  HMTD and TATP

III.3.1.4 Hydrogen Peroxide

III.3.2 Potential Pitfalls

III.3.3 Conclusions

III.4 Matching Matchsticks

III.4.1 13C–Bulk Isotope Analysis

III.4.2 18O–Bulk Isotope Analysis

III.4.3 2H–Bulk Isotope Analysis

III.4.4 Matching Matches from Fire Scenes

III.4.5 Conclusions

III.5 Provenancing People

III.5.1 Stable Isotope Abundance Variation in Human Tissue

III.5.1.1 Hair and Nails

III.5.1.1.1 Characteristics of Hair

III.5.1.1.2 Characteristics of Nails

III.5.1.1.3 Diagenetic Changes of Keratin

III.5.1.1.4 2H Isotopic Record in Hair and Nails

III.5.1.1.5 18O Isotopic Record in Hair and Nail

III.5.1.1.6 13C Isotopic Record in Hair and Nail

III.5.1.1.7 15N Isotopic Record in Hair and Nail

III.5.1.2 Bone and Teeth

III.5.1.2.1 Chemical Composition of Bone and Teeth

III.5.1.2.2 Static versus Remodelling Tissue Compartments

III.5.1.2.3 Diagenetic Changes of Bone and Teeth Mineral

III.5.1.2.4 Diagenetic Changes of Type I Collagen

III.5.1.2.5 18O Isotopic Record in Carbonate and Phosphate from Bio–apatite

III.5.1.2.6 13C Isotopic Record in Carbonate from Bio–apatite

III.5.1.2.7 Isotopic Record in Type I Collagen

III.5.1.3 Trophic Level Shift Effect on Stable Isotope Abundance Values in Human Tissue

III.5.2 Case Examples

III.5.2.1 The Skull from the Sea

III.5.2.2 A Human Life Recorded in Hair

III.5.2.3 Found in Newfoundland

III.5.2.4 The Case of The Scissor Sisters

III.5.2.5 Too Short a Life

III.5.2.6 "Saltair Sally"

III.5.2.7 A Tale of Two Cultures

III.5.3 Conclusions and Caveats

III.6 Stable Isotope Forensics of other Physical Evidence

III.6.1 Microbial Agents

III.6.2 Toxins and Poisons

III.6.3 Paper, Plastic (Bags) and Parcel Tape

III.6.3.1 Paper

III.6.3.2 Plastic and Plastic Bags

III.6.3.3 Parcel Tape

III.6.4 Conclusions

III.7 Evaluative Interpretation of Forensic Stable Isotope Signatures

III.7.1 Not Scale Referenced Ô–Values

III.7.2 Unresolved Contradictory Data

III.7.2.1 Example: ′Geographic Provenance of a Murder Victim′

III.7.2.2 Example: ′Manslaughter due to Negligence′

III.7.3 Foregone Conclusions

III.7.4 Logical Fallacies

III.7.5 Untested Assumptions

III.7.6 Conclusions

III.8 Summary of Part III

Appendix III: An Abridged List of Forensic Stable Isotope Laboratories world–wide

References Part III

Recommended Reading

Author s Biography

Acknowledgements

Index

Wolfram Meier–Augenstein, PhD is Professor in Stable Isotope Forensics at the Robert Gordon University in Aberdeen, Scotland, UK. He is a registered expert advisor with the National Crime Agency (NCA, UK) and holds a Diplom–Chemiker degree, as well as a Doctorate in Bio–organic Chemistry, both awarded by the University of Heidelberg, Federal Republic of Germany. Dr. Meier–Augenstein has assisted police forces and coroners′ offices around the world in murder enquiries and drug–related related crime investigations.