DOCSLIB.ORG

Forensic Chemistry

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Forensic Chemistry AccessScience from McGraw-Hill Education Page 1 of 8 www.accessscience.com Forensic chemistry Contributed by: Jay A. Siegel Publication year: 2014 Part of the field of forensic science, which is defined as the application of the methods of science to legal matters, either civil or criminal. There is no precise definition of forensic chemistry. As practiced in forensic science laboratories today, it goes well beyond the application of the methods of chemistry to the analysis of evidence in civil and criminal cases. Many forensic chemists use a microscope to analyze evidence as much or more than any analytical chemistry instrument. In some cases, such as the morphological analysis of hair, no chemistry may be done on the evidence even though a forensic chemist may do the analysis. Increasingly, forensic chemical analysis may be performed on types of evidence that are not normally considered to be chemical evidence. These include chemical development of fingerprints and gunshot residue and chemical analysis of inks and papers in cases involving questioned documents. In many of these situations, the analysis is not done by forensic chemists in the chemistry section, but by fingerprint, firearms, or questioned-document examiners. See also: CRIMINALISTICS . Types of Forensic Chemical Evidence In theory, virtually any material can become evidence in a civil or criminal matter and may thus be subject to forensic chemical analysis. In practice, there a few common types of evidence that are largely analyzed, at least in part, by chemical means. The following are the major types. Controlled substances and other drugs These are sometimes called illicit drugs, dangerous drugs, abused drugs, or street drugs. In the United States, they are referred to as controlled substances because they are included within a set of federal Uniform Controlled Substances statutes. Half of all criminal cases submitted to U.S. forensic science laboratories are controlled-substance cases. Controlled substances can be found in powdered, solid, or liquid forms; as tablets or capsules; or as plants and plant extracts. They can also be found inside the body in blood or other body fluids. In the latter cases, the drugs are usually analyzed by a forensic toxicologist rather than a forensic chemist, although both disciplines use the same type of analytical procedures and instruments, and forensic toxicology a really a branch of forensic chemistry. Half of all forensic toxicology cases involve the analysis of ethyl alcohol (ethanol). Ethanol is not a controlled substance and is subject to control by drunk driving and public intoxication laws. Alcohol is analyzed in blood or breath using analytical chemical methods such as gas chromatography, infrared spectroscopy, and visible spectroscopy. See also: FORENSIC TOXICOLOGY . AccessScience from McGraw-Hill Education Page 2 of 8 www.accessscience.com Blood and other body fluids Most forensic scientists and crime labs include the analysis of blood and other body fluids in the area of forensic biology, but many of the methods of analysis used in these types of evidence are essentially analytical chemistry. Presumptive screening tests for body fluids are usually chemical tests, although some are immunological. Even DNA extractions, amplifications, and separations by electrophoresis and subsequent fluorescence analysis involve chemical tests. See also: FORENSIC BIOLOGY . Trace evidence Trace evidence does not have a specific definition. It usually means evidence that occurs in such small quantities that it is examined principally by microscopy of one form or another. Some cases involve such small quantities of evidence that only a microscope is used for analysis. In spite of such heavy reliance on microscopy, trace evidence is usually analyzed by forensic chemists who are trained in the principles and uses of microscopes that range from low-power stereomicroscopes to scanning electron microscopes. Included in the area of trace evidence are explosive and fire residues, hairs and fibers, glass and soils, plastics and other polymers, inks and papers, paints and coatings, and miscellaneous materials. Not only are microscopes themselves used in these analyses, but also instruments that incorporate microscopes, such as microspectrophotometers, are used. Pattern evidence Forensic chemistry, but perhaps not forensic chemists, is becoming increasingly involved in the analysis of pattern evidence. This includes fingerprints, firearms, and questioned documents as well as footwear and tire treads. Few are the days in which fingerprints were lifted from surfaces by brushing them with a fine-particle fingerprint powder. Today there are many types of chemicals that react with the oils, fats, and proteins in fingerprint residues, forming characteristic color reactions that can be used to visualize latent fingerprints. The technique of “superglue fuming” employs cyanoacrylate (adhesive) to coat and visualize latent fingerprints. A variety of dyes can then be used along with appropriate lasers or alternative light sources to further enhance the print. See also: FINGERPRINT . Chemical methods have long been used to visualize gunshot residues. Reagents are applied to garments or other surfaces and color the materials that are ejected with a bullet from the barrel of a gun. Analytical chemical methods can be used to identify particles of gunshot primer that are deposited on the hands of someone who fires a weapon. As mentioned previously, ink and paper analysis is becoming increasingly important in the examination of questioned documents. Most of the methods used to characterize inks and paper involve analytical chemistry. See also: ANALYTICAL CHEMISTRY . AccessScience from McGraw-Hill Education Page 3 of 8 www.accessscience.com Theory and Purpose of Chemical Analysis of Evidence Two principal processes are involved in the analysis of forensic evidence: identification and comparison. Identification is the process of discovering and elucidating relevant chemical and physical properties of an object or material. For some forensic evidence, identification may include quantitative as well as qualitative analysis. All evidence is identified to one degree or another. What makes forensic chemistry unique with respect to other types of chemistry is that there is nearly always a goal of associating the evidence from a crime scene with someone or something that is alleged to have been involved with the crime. This association is always made by a comparison of the evidentiary material with a known person or object. The ultimate goal of forensic examination is to be able to associate evidence with just one person or object, to the exclusion of all others. This association is termed individualization. Individualization is seldom accomplished by discovering and elucidating the chemical properties of the evidence. If individualization is possible, it is always accomplished by evaluating physical characteristics such as the pattern of ridges in a fingerprint, the pattern of markings put on a bullet by the barrel during firing, or the unique characteristics of a person’s handwriting. The sole exception to this is when DNA from biological material is compared to DNA from a suspect or victim, or a crime scene. In DNA typing, certain repeat sequences of DNA are characterized and compared. Population frequencies of these sequences in the human genome are known, and the probability of a chance occurrence can be computed. The chance that two people will have exactly the same DNA type is extremely small, such that a concurrence is a strong indicator of uniqueness and thus individualization. See also: QUALITATIVE CHEMICAL ANALYSIS ; QUANTITATIVE CHEMICAL ANALYSIS . Because it is otherwise not possible to individualize chemical evidence to a particular source, the goal is to characterize it chemically given the limitations of time and quantity of evidence and the purposes of the analysis. The amount of chemical testing that is done on evidence depends on the quantity, quality, and type of evidence that is present. Schemes of Chemical Analysis For most types of chemical evidence, there are some well-defined schemes of analysis. Even for those types for which schemes have not been developed, there are some basic principles that apply in most cases. These principles, to the extent possible, are described below. Evidence must be preserved An example of this occurs in the analysis of ink on a questioned document. Examiners are often called on to compare the ink on two documents or to compare the ink on a document with that in a writing implement such as a pen. This usually involves removing some of the ink for chemical analysis without defacing the document. It is not permissible to cut out pieces of the writing on the document, because it may have to be analyzed for other purposes such as handwriting characteristics. Such destruction is called spoilage and can result in the evidence being inadmissible in court. Tiny hole punches are often used in such cases. The hole in the punch has a diameter AccessScience from McGraw-Hill Education Page 4 of 8 www.accessscience.com that is less than the width of the writing stroke, so the essential characteristics of the handwriting are maintained. Some instrumental techniques, such as laser Raman spectrometry, allow the ink to be analyzed on the paper. Evidence must be conserved In cases in which forensic chemical analysis would consume all of the evidence, special arrangements and notifications must be made so that the prosecution and defense are aware of the limitations and the defendant’s rights are preserved. This means that the natural order of testing (see below) may be disrupted so that nondestructive tests are done first. Testing Within the limitations imposed by the need to conserve evidence, testing usually proceeds from the least to the most discriminating. If the evidence is an unknown powder or liquid, a number of screening tests can be applied to get into the right “ballpark” and narrow down the possibilities. The next test may be separation by thin-layer, gas–liquid, or liquid chromatography to ascertain the number of substances in the sample.
Load more

Recommended publications
  • Forensic Chemistry (4 Credit Hrs) Course Description: Surve
    CHEMISTRY 107 FORENSIC CHEMISTRY BULLETIN INFORMATION CHEM 107 – Forensic Chemistry (4 credit hrs) Course Description: Surveys chemical aspects of criminal investigation and adjudication including drug, arson, DNA, paint, and fiber identification. Note: Three lecture and three laboratory hours per week. SAMPLE COURSE OVERVIEW This course is an introduction to forensic chemistry intended for non-science majors. The course examines the many ways that chemical principles and scientific techniques are applied in modern crime investigation: the chemical characteristics of fuels and explosives as well as arson-related methods; other ways of identifying criminals through chemical processes, including blood and bodily fluid analyses, the chemical characteristics found in paints, fibers, hair, DNA, and fingerprinting; and the chemical properties of drug analysis. Through readings, lectures, demonstrations, homework, and laboratory exercises, students learn the fundamentals of forensic chemistry and its applications in crime investigation and adjudication. Student learning is evaluated through exams, assignments, participation in class discussions and activities, a case study project, and laboratory reports. ITEMIZED LEARNING OUTCOMES Upon successful completion of CHEM 107, students will be able to: 1. Demonstrate understanding of the scientific method. 2. Discuss the basic principles, concepts, terms, and scientific techniques associated with forensic chemistry. 3. Evaluate the relationships between science, technology, and society as these affect forensic issues. By specifically being able to: Identify steps of scientific method; describe and perform various forensic analytical techniques. Explain the characteristics of fuels and explosives, and their chemical evidence. Classify drugs, identify their chemical properties, and conduct their analysis. Describe the characteristics and properties of various materials such as hair, paint, polymers, fibers.
    [Show full text]
  • Soft and Robust Identification of Body Fluid Using Fourier Transform
    www.nature.com/scientificreports OPEN Soft and Robust Identifcation of Body Fluid Using Fourier Transform Infrared Spectroscopy Received: 14 February 2018 Accepted: 21 May 2018 and Chemometric Strategies for Published: xx xx xxxx Forensic Analysis Ayari Takamura1,2, Ken Watanabe1, Tomoko Akutsu1 & Takeaki Ozawa2 Body fuid (BF) identifcation is a critical part of a criminal investigation because of its ability to suggest how the crime was committed and to provide reliable origins of DNA. In contrast to current methods using serological and biochemical techniques, vibrational spectroscopic approaches provide alternative advantages for forensic BF identifcation, such as non-destructivity and versatility for various BF types and analytical interests. However, unexplored issues remain for its practical application to forensics; for example, a specifc BF needs to be discriminated from all other suspicious materials as well as other BFs, and the method should be applicable even to aged BF samples. Herein, we describe an innovative modeling method for discriminating the ATR FT-IR spectra of various BFs, including peripheral blood, saliva, semen, urine and sweat, to meet the practical demands described above. Spectra from unexpected non-BF samples were efciently excluded as outliers by adopting the Q-statistics technique. The robustness of the models against aged BFs was signifcantly improved by using the discrimination scheme of a dichotomous classifcation tree with hierarchical clustering. The present study advances the use of vibrational spectroscopy and a chemometric strategy for forensic BF identifcation. Forensic science is an applied research feld that aims to develop and validate analytical methods for criminal investigation and justice. Although research interest in forensics is quite diversifed, the analysis of biological samples collected at a crime scene is undoubtedly one of the most important tasks owing to the ability to identify criminal acts and suspects by DNA profling.
    [Show full text]
  • Faculty of Science Internal Bylaw of Graduate Studies "Program Curricula and Course Contents" 2016
    . Faculty of Science Internal Bylaw of Graduate Studies "Program Curricula and Course Contents" 2016 Table of Contents Page 1-Mathematics Department Mathematics Programs 1 Diplomas Professional Diploma in Applied Statistics 2 Professional Diploma in Bioinformatics 3 M.Sc. Degree M.Sc. Degree in Pure Mathematics 4 M.Sc. Degree in Applied Mathematics 5 M.Sc. Degree in Mathematical Statistics 6 M.Sc. Degree in Computer Science 7 M.Sc. Degree in Scientific Computing 8 Ph.D. Degree Ph. D. Degree in Pure Mathematics 9 Ph. D Degree in Applied Mathematics 10 Ph. D. Degree in Mathematical Statistics 11 Ph. D Degree in Computer Science 12 Ph. D Degree in Scientific Computing 13 2- Physics Department Physics Programs 14 Diplomas Diploma in Medical Physics 15 M.Sc. Degree M.Sc. Degree in Solid State Physics 16 M.Sc. Degree in Nanomaterials 17 M.Sc. Degree in Nuclear Physics 18 M.Sc. Degree in Radiation Physics 19 M.Sc. Degree in Plasma Physics 20 M.Sc. Degree in Laser Physics 21 M.Sc. Degree in Theoretical Physics 22 M.Sc. Degree in Medical Physics 23 Ph.D. Degree Ph.D. Degree in Solid State Physics 24 Ph.D. Degree in Nanomaterials 25 Ph.D. Degree in Nuclear Physics 26 Ph.D. Degree in Radiation Physics 27 Ph.D. Degree in Plasma Physics 28 Ph.D. Degree in Laser Physics 29 Ph.D. Degree in Theoretical Physics 30 3- Chemistry Department Chemistry Programs 31 Diplomas Professional Diploma in Biochemistry 32 Professional Diploma in Quality Control 33 Professional Diploma in Applied Forensic Chemistry 34 Professional Diploma in Applied Organic Chemistry 35 Environmental Analytical Chemistry Diploma 36 M.Sc.
    [Show full text]
  • FORENSIC CHEMISTRY David Collins Brigham Young University—Idaho
    Collins_Forensic.qxd 9/21/06 3:40 PM Page 1 FORENSIC CHEMISTRY David Collins Brigham Young University—Idaho Forensic scientists play a key role in criminal investigations. Fingerprints collected from a suspect will be compared to fingerprints collected at the crime scene after being developed in the lab by a forensic scientist. 1 Introduction to Forensic Science 2 Forensic Chemistry 3 Theory of Forensic Analysis 4 Fingerprint Development 5 Presumptive Drug Analysis 6 Soil Analysis 7 Thin Layer Chromatography and Ink Analysis 8 Conclusions Charles D. Winters rime-time television is chock-full of drama centered on the criminal jus- tice system. Programs such as CSI: Crime Scene Investigation, Law & Order, PCriminal Minds, and Cold Case carry the viewer through stimulating, yet nearly impossible-to-solve, investigations that culminate with the evidence re- vealing the entire untold story behind a crime in one hour or less. In real life Cengagethe collection and analysis of evidence involves painstaking Learningcare and rigorous application of scientific principles. Have you ever wondered how evidence in an actual case tells the story, what information each item of evidence holds, and how this information can be elucidated in a crime laboratory? In this chapter we will explore the world of forensic chemistry, focusing on the theory and processes of forensic analysis and showing the role that chemistry plays in criminal investigations. © 2007 Thomson Brooks/Cole, a part of the Thomson Corporation. Thomson, the Star logo, and Brooks/Cole are trademarks used herein under license. ALL RIGHTS RESERVED. No part of this work covered by the copyright hereon may be reproduced or used in any form or by any means — graphic, electronic, or mechanical, including photocopying, recording, taping, Web distribution or information storage and retrieval systems — without the written permission of the publisher.
    [Show full text]
  • Chemical Analysis of Medicinal and Poisonous
    CHEMICAL ANALYSIS OF MEDICINAL AND POISONOUS PLANTS OF FORENSIC IMPORTANCE IN SOUTH AFRICA P. A. STEENKAMP Submitted in fulfilment of the requirements for the degree PHILOSOPHIAE DOCTOR in CHEMISTRY in the FACULTY OF SCIENCE at the UNIVERSITY OF JOHANNESBURG Promotor: PROF. F.R. VAN HEERDEN Co-promotor: PROF. B-E. VAN WYK MAY 2005 Created by Neevia Personal Converter trial version http://www.neevia.com Created by Neevia Personal Converter trial version ACKNOWLEDGEMENTS I wish to express my sincere appreciation to all whose assistance and advice contributed to the creation of this thesis, and in particular the following: Professor F.R. van Heerden , my promotor, for her continued interest, advice, invaluable guidance with the chemical aspects of the project and NMR data interpretation of chapters six, seven and eight. Professor B-E. van Wyk , my co-promotor, for his enthusiasm, editorial guidance and invaluable assistance with the botanical aspects of the project. The Department of Health for their financial support and the Forensic Chemistry Laboratory for the use of their infrastructure to complete this research. Doctor L.H. Steenkamp, my wife, for her love, patience, assistance and encouragement. My children, Anton and Andries, for their patience, support and understanding. My colleagues of the Forensic Toxicology Research Unit for their support. Miss Kim Lilley of the Waters Corporation (USA) for her technical support and advice on mass spectrometry. My mother for her unwavering support and encouragement. My friends and family for their interest and encouragement. Finally, but most important, I want to express my gratitude to GOD for His grace and provision, and for the ability and opportunity to study a small part of His wonderful creation.
    [Show full text]
  • Forensic Science Timeline
    The Forensic Science Timeline can also be found as an appendix in our recently published book Principles and Practice of Forensic Science: The Profession of Forensic Science http://forensicdna.com/Bookstore/index.html See also the Forensic Science Bibliography http://forensicdna.com/Bibliography.html This is a “work in progress” Please e-mail comments and suggestions http://forensicdna.com/~emailforms/emailtimeline.html This work is copyright © of Norah Rudin and Keith Inman all rights are reserved It may not be reprinted, distributed, or posted on any other web site without explicit permission. If you are viewing this page, or any facsimile of it on a domain other than forensicdna.com, you are viewing pirated material. If you would like to provide this content to the viewers of your web site, please feel free to link directly to this page. Forensic Science Timeline updated 2/7/02 BCE Evidence of fingerprints in early paintings and rock carvings of prehistoric humans 700s Chinese used fingerprints to establish identity of documents and clay sculpture, but without any formal classification system. (1000) Quintilian, an attorney in the Roman courts, showed that bloody palm prints were meant to frame a blind man of his mother’s murder. 1248 A Chinese book, Hsi Duan Yu (the washing away of wrongs), contains a description of how to distinguish drowning from strangulation. This was the first recorded application of medical knowledge to the solution of crime. 1609 The first treatise on systematic document examination was published by François Demelle of France 1686 Marcello Malpighi, a professor of anatomy at the University of Bologna, noted fingerprint characteristics.
    [Show full text]
  • Whence Has Forensic Geochemical Hydrocarbon Fingerprinting Come
    Journal of Environmental Protection, 2016, 7, 303-311 Published Online February 2016 in SciRes. http://www.scirp.org/journal/jep http://dx.doi.org/10.4236/jep.2016.73026 The History of Hydrocarbon Analyses: Whence Has Forensic Geochemical Hydrocarbon Fingerprinting Come Michael J. Wade1*, Dennis Stainken2 1Wade Research, Inc., Marshfield, USA 2Princeton-Somerset Group, Inc., Hillsborough, USA Received 18 January 2016; accepted 23 February 2016; published 26 February 2016 Copyright © 2016 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/ Abstract The current techniques used in forensic geochemical hydrocarbon fingerprinting have their gene- sis along with the evolution of gas chromatography as it applies to hydrocarbon research. In the United States, a small group of government and academic chemists and marine scientists pio- neered the use of gas chromatography in the identification of both natural and petroleum-derived hydrocarbons. Natural products were a primary focus until the research direction was altered somewhat by marine oil spills, accidents releasing crude oil and refined petroleum products to the world’s coastal marine environment, giving rise to concerns regarding biogeochemical impacts. Application of oil spill research continued from that point so that the geochemical research begun in the late 1960s and early 1970s now forms a major component of investigations of petroleum releases both in the aquatic and terrestrial environments. As the capabilities for the identification of individual hydrocarbons in a variety of petroleum products improved with basic advances in chromatographic technology, new applied sciences in forensic geochemical hydrocarbon finger- printing have emerged.
    [Show full text]
  • Forensic Applications of IR/FTIR
    Journal of Forensic Chemistry and Toxicology39 Volume 3 Number 1, January - June 2017 Review Article DOI: http://dx.doi.org/10.21088/jfct.2454.9363.3117.5 Forensic Applications of IR/FTIR A.K. Jaiswal*, N.G. Giri**, Anil Kumar Jaiswal***, Nilima Samal****, P. Sharma*****, T. Millo******, S.K. Gupta******* Authors Affiliation: *Chemist ******Professor Reprints Requests: A.K. Jaiswal, Chemist, Deptt. of *******Professor and Head, Deptt. of Forensic Medicine and Forensic Medicine and Toxicology, All India Institute of Toxicology, All India Institute of Medical Sciences, Ansari Medical Sciences, Ansari Nagar, New Delhi-110029. Nagar, New Delhi-110029. **Assistant Professor, Deptt. of E-mail: [email protected] Chemistry, Shivaji College (University of Delhi) Raja Garden, New Delhi 110 027. ***Assistant Professor, Department of Mathematics, St. Andrew’s PG College, Gorakhpur, UP. ****Assistant Professor *****Senior Scientific Officer (Chemistry), LNJN NICFS, Sector-3, Outer Ring Road, Rohini, Delhi- 110085. Received on 13.02.2017, Accepted on 23.02.2017 Abstract Infra-Red spectroscopy plays important role for analysis of several compounds, metals etc. Its use is readily understood from breadth of its applications. The range of material that can be analyzed by IR/FTIR is essentially unlimited. Applications are found in diverse fields such as forensic science, pharmaceuticals, food and agriculture, biological and clinical chemistry, environmental chemistry and many others. Keywords: IR; FTIR; Dipole; Instrument etc. Introduction must go a net change in dipole moment because of its vibrational or rotational motion [1]. • Absorption of IR radiation by a molecule is the basis of this kind of spectroscopy • No net change in dipole moment occurs during the vibration of homonuclear species such as O , • It is also called absorption spectroscopy 2 N2, H2, and Cl2 and hence these compounds do • The extent of this absorption depends on the not absorb in the IR region.
    [Show full text]
  • An Access-Dictionary of Internationalist High Tech Latinate English
    An Access-Dictionary of Internationalist High Tech Latinate English Excerpted from Word Power, Public Speaking Confidence, and Dictionary-Based Learning, Copyright © 2007 by Robert Oliphant, columnist, Education News Author of The Latin-Old English Glossary in British Museum MS 3376 (Mouton, 1966) and A Piano for Mrs. Cimino (Prentice Hall, 1980) INTRODUCTION Strictly speaking, this is simply a list of technical terms: 30,680 of them presented in an alphabetical sequence of 52 professional subject fields ranging from Aeronautics to Zoology. Practically considered, though, every item on the list can be quickly accessed in the Random House Webster’s Unabridged Dictionary (RHU), updated second edition of 2007, or in its CD – ROM WordGenius® version. So what’s here is actually an in-depth learning tool for mastering the basic vocabularies of what today can fairly be called American-Pronunciation Internationalist High Tech Latinate English. Dictionary authority. This list, by virtue of its dictionary link, has far more authority than a conventional professional-subject glossary, even the one offered online by the University of Maryland Medical Center. American dictionaries, after all, have always assigned their technical terms to professional experts in specific fields, identified those experts in print, and in effect held them responsible for the accuracy and comprehensiveness of each entry. Even more important, the entries themselves offer learners a complete sketch of each target word (headword). Memorization. For professionals, memorization is a basic career requirement. Any physician will tell you how much of it is called for in medical school and how hard it is, thanks to thousands of strange, exotic shapes like <myocardium> that have to be taken apart in the mind and reassembled like pieces of an unpronounceable jigsaw puzzle.
    [Show full text]
  • Paul D. Boehm, Ph.D
    Paul D. Boehm, Ph.D. Corporate Vice President & Principal Scientist | Environmental & Earth Sciences 1 Mill and Main Place, Suite 150 | Maynard, MA 01754 (978) 461-4601 tel | [email protected] Professional Profile As an environmental scientist and strategic advisor on environmental issues, Dr Boehm has conducted investigations for, consulted with, and advised industrial, legal, and government clients on scientific matters involving regulatory issues and legal claims associated with chemical contaminants in the environment. The main pillars of his professional work include analyzing and explaining the environmental distributions and fates hazardous chemical and petroleum releases, and ecological effects from chemical exposures. His work also includes the evaluation risks and damages due to climate change factors and extreme weather events. Dr. Boehm is a leading practitioner and a recognized expert in the fields of natural resource damage assessments (NRDA) for oil spills and contaminated sites; maritime environmental incidents; natural gas geochemistry; and the environmental and forensic chemistry of crude and refined petroleum; polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and other organic chemicals; and natural gas geochemistry. His practice also directly involves the environmental fate and transport of chemicals as well as exposure and impact assessment. Dr. Boehm's consulting work has focused both historical legacy and contemporary chemical releases and migration from facilities including: oil refineries, fuel terminals, pipelines, and offshore platforms; manufactured gas plants (MGPs); integrated steel mills; pulp and paper mills; other active and legacy manufacturing sites; and natural gas storage fields. Many of his projects involve aspects of historical reconstruction of chemical releases; chemical fingerprinting; divisibility and apportionment; allocation at CERCLA and OPA multiparty sites; and chemical exposure and injury assessment.
    [Show full text]
  • Selected Possibilites of Using Infrared Spectroscopy in Criminalistics
    STRUĆNI RAD (PROFESSIONAL PAPER) UDK: 343.983.2 Ľuboš Cehlárik, Mgr. PhD student of Criminalistic and Forensic Science Department Academy of the Police Force, Bratislava, Slovakia Phone: +421 9610 57473 E-mail: [email protected] SELECTED POSSIBILITES OF USING INFRARED SPECTROSCOPY IN CRIMINALISTICS Abstract: Infrared spectroscopy is one of the most commonly used spectroscopic methods in criminalistics, through which various kinds of criminalistic traces can be explored. It finds wide application in academic research, but also in research of forensic laboratories in order to obtain results ap- plicable in criminalistic practice. The paper provides information about selected possibilities of using Fourier transform infrared spectroscopy and its modifications in investigation of specific criminalistic traces such as documents, banknotes, cosmetics, blood traces and adhesive materials. Keywords: infrared spectroscopy, chemometrics, paper, banknotes, hair cosmetics, lipstick, blood traces, adhesive tape 55 L. Cehlárik - SELECTED POSSIBILITIES OF USING INFRARED SPECTROSCOPY IN CRIMINALISTICS, str. 55-70 _____________________________________________________________________________ 1. A BRIEF INTRODUCTION TO THE BASIC THEORETICAL BASIS OF INFRARED SPECTROSCOPY Infrared spectroscopy (IR spectroscopy) is a physico-chemical method that deals with the measurement and evaluation of absorption spectra of substances in the wavelength range 800 nm to 1000 μm (wavelength range from 12500 to 10 cm- 1). The advantage of infrared spectroscopy is the possibility to study substances in all dimensions and states, such as liquid substances, solutions, pastes, powder samples, paints, gases, different surfaces, polymers, organic and inorganic compounds, biological samples, oils, catalysts, minerals, organometallic compounds. IR has its irreplaceable role in the identification of molecules, the detection of new compounds, the study of chemical equilibria and the kinetics of chemical reactions.
    [Show full text]
  • Some Applications of Gas Chromatography to Forensic Chemistry Daniel T
    Journal of Criminal Law and Criminology Volume 54 Article 10 Issue 1 March Spring 1963 Some Applications of Gas Chromatography to Forensic Chemistry Daniel T. Dragel Ed Beck Andrew H. Principe Follow this and additional works at: https://scholarlycommons.law.northwestern.edu/jclc Part of the Criminal Law Commons, Criminology Commons, and the Criminology and Criminal Justice Commons Recommended Citation Daniel T. Dragel, Ed Beck, Andrew H. Principe, Some Applications of Gas Chromatography to Forensic Chemistry, 54 J. Crim. L. Criminology & Police Sci. 96 (1963) This Criminology is brought to you for free and open access by Northwestern University School of Law Scholarly Commons. It has been accepted for inclusion in Journal of Criminal Law and Criminology by an authorized editor of Northwestern University School of Law Scholarly Commons. SOME APPLICATIONS OF GAS CHROMATOGRAPHY TO FORENSIC CHEMISTRY* DANIEL T. DRAGEL, ED BECK AND ANDREW H. PRINCIPE Captain Daniel T. Dragel is Director, Chicago Police Crime Detection Laboratory. Captain Dragel is a graduate chemist from the University of Illinois and holds a law degree from DePaul University, Chicago. He is a fellow of the American Academy of Forensic Sciences and a member of the American Chemical Society and the Illinois Bar Association. Ed Beck, Ph.D. is Group Leader in the Analytical Section Research and Grocery Products Di- vision, Armour & Company, Chicago. He is a member of the American Oil Chemists Society, the American Chemical Society, and Sigma Xi. Andrew H. Principe is Staff Chemist at the Chicago Police Crime Detection Laboratory. He is a graduate of Roosevelt University, Chicago, and a fellow of the American Academy of Forensic Sciences and a member of the American Chemical Society.-EDIoR.
    [Show full text]