Forensic Toxicology

Medico-Legal Case Studies

Kalipatnapu N. Rao

• Publisher: CRC Press
• Year: 2012
• ISBN:
  9781466558960
• Edition: 1
• Topic: Law
• Subtopic: Forensic Science
• Index: Law

Modern technology using state-of-the-art equipment can now identify almost any toxin relevant to a legal issue. Techniques include gas chromatography, mass spectrometry, high-pressure liquid chromatography, and the combination of these methods. Forensic Toxicology: Medico-legal Case Studies demonstrates how the science of forensic toxicology acts a

Historical Perspectives
in Toxicology

1

1.1 Toxicology

Toxicology can be defined as a science dealing with the adverse effects of chemicals and toxins on living cells. The word toxin is derived from Greek, which means a poison. The effects on the cell are described as toxicity. The person who is knowledgeable on the effects of toxins is called a toxicologist. The recognition of toxicology as an independent science is quite recent and its evolution as a scientific discipline combining the knowledge of biology and chemistry has been quite rapid. Further impetus to this evolution is due to phenomenal developments in medicine. The discovery of new medicines to alleviate human pain and suffering necessitated the discovery of new analytical methods to monitor the drug levels in body fluids. The abuse of prescription medications requires the detection of these drugs in body fluids. Thus, the modern, clinical toxicology laboratory with state-of-the-art equipment evolved. This required moving what was once a small laboratory in a physician’s office to a centralized laboratory. This development of a centralized laboratory and its organization will be discussed in detail in other chapters. Another significant development is that it required the services of a forensic toxicologist. As society evolved into organized government, well-established legislative bodies, and established judiciary and law enforcement, forensic toxicologists were required to interpret the results obtained in a central laboratory. Thus, a toxicologist evolved from a homicidal prisoner in earlier times to a scientist who helps physicians and lawyers to identify the toxin causing intoxication on their clients (1–6).

1.2 Poison

A poison was considered a coward’s weapon. A poison is defined as a chemical that can sicken or kill another organism. An ideal poison is one that is effective in a very small dose and difficult to detect. As the times changed, obscure poisons were introduced. Some of them were lethal drugs like fentenyl, insulin, and muscle relaxants. Some household chemicals like antifreeze were used to commit murder for insurance money. Arsenic was a common agent to commit murder (7). With the growth of the science of clinical toxicology and forensic toxicology, the development of centralized laboratory facilities, and the availability of sophisticated analytical tools like gas chromatography (GC), gas chromatography/mass spectrometry (GC-MS), high-pressure liquid chromatography (HPLC), and liquid chromatography/mass spectrometry (LC-MS) it became easy to detect almost any poison. With the use of an inductively coupled plasma (ICP) mass spectrometer, it is now possible to detect and quantitate up to 70 elements in the periodic table. It is also possible to extract toxin from the hair and fingernails and quantify metals, drugs, or a toxin trapped in these matrices. Today, no matter the poison, a method is easily being developed to detect it (6). If the present analytical methods are inadequate, forensic toxicologists develop new methods to detect and quantify any new toxin that is being used and abused.

The growth of complex centralized forensic toxicology laboratory facilities is discussed in Chapter 2.

1.3 Industrial Revolution

During the industrial revolution, there were explosive discoveries of chemicals. These chemicals are useful as well as harmful to humans. These chemicals found use as medicines and in the treatment of diseases. Discovery of pesticides enhanced food production. Introduction of plastics facilitated the storage and transport of a variety of products. The use of chemicals and the waste products released into the environment created toxic reactions in humans and animals. It was soon realized that all substances are poisons and there are none that are not poisons. The right dose distinguishes a poison from a remedy (Paracelus, 1492–1541). Industrial chemicals were found to be quite harmful when exposed in higher doses. This resulted in toxicology branching off into environmental toxicology, pharmacology, general toxicology, clinical toxicology, forensic toxicology, and occupational toxicology (5,6).

1.4 Effect of Insurance Industry on Homicides

The growth of the insurance industry and the ready availability of arsenictrioxide, which is a tasteless compound without any smell, gave a stimulus to homicidal poisoning for personal gain (7). Even in modern times, arsenic is being used despite the fact that toxicologists can easily detect this element in body fluids of victims. It is indeed interesting to hear about homicides committed using arsenic on family members for insurance money. A forensic toxicology laboratory can easily detect arsenic in the body and aid law enforcement to bring to justice the perpetrators of these homicides.

1.5 What the Book Is About

This book is essentially about the exciting science of forensic toxicology with illustrative medico-legal case studies to show how this science acts as a bridge between medicine and law. Both of these professions strive to make the life of their clients better. The medical profession protects the physical health of a person, while the legal profession protects the freedom and well-being of a person. Chapters 2 and 3 are devoted to explaining the organization and operations involved in hospital settings. Chapters 7 and 8 are devoted to discussing the nature of several toxins with illustrative medical cases that might come to a hospital. Chapter 9 explains the nature and operations of the American legal system. Finally, legal cases illustrate how law enforcement and the court system try to protect the freedom of an individual as well as that of society as a whole.

As stated earlier, the role of a toxicologist has changed from a homicidal poisoner to an essential important scientist for medico-legal professionals. Poisons were used for centuries as a weapon of choice to commit murder. When used in the right dose, a poison can effectively kill the victim mimicking death due to natural causes. Toxicologists play an important role in detecting the cause of death. A toxicologist is called upon to determine whether a death is accidental, suicide, or homicide. In addition, forensic toxicologists play a pivotal role in determining substance abuse or an adverse reaction to a prescription medication. A toxicologist may be asked to test for carbon monoxide poisoning, or the presence of γ-hydroxy butyrate (GHB) and other date rape drugs. Society expects a toxicologist to identify environmental pollution and adverse reactions to pesticide exposure. A toxicologist is expected to identify accidental deaths secondary to the simultaneous use of alcohol and drugs such as opium, morphine, and heroin. A toxicologist is asked to identify commonly used poisons to commit crimes such as atropine, strychnine, thallium, antimony, arsenic, and cyanide (8).

In the emergency room, physicians are asked to find antidotes for overdose of drugs and poisons. Indeed, such antidotes are available. Tylenol overdose is treated with N-acetyl cysteine, warfarin overdose is treated with vitamin K, narcotic/opioid overdose is treated with naloxone, iron and other heavy metal overdoses are treated with deforoximine, effects of benzodiazepines are treated with flumazenil, ethylene glycol poisoning is treated with ethanol/fomepizole, and methanol poisoning is treated with ethanol or fomepizole (6,8).

References

  1. Levine, B. Principles of Forensic Toxicology. AACC Press, Washington, D.C., 1999.

  2. Karch, S. B. Karch’s Pathology of Drug Abuse, 3rd ed. CRC Press, New York, 2001.

  3. Burtis, C. A. and Ashwood, E. R. (Eds.) Tietz Textbook of Clinical Chemistry, 2nd ed. W.B. Saunders Company, Philadelphia, PA, 1994.

  4. Trestrail, J. A. Criminal Poisoning. Humana Press, Totowa, NJ, 2000.

  5. Monosson, E. History of toxicology. www.eoearth.org/article/History_of_toxicology.1–3, 2008.

  6. Borzelica, J. The art, the science and the seduction of toxicology. An evolutionary development. In: Principles and Methods of Toxicology, Hayes, A. (Ed.). Taylor & Francis, London, 2001.

  7. BBC Home. A brief history of poisoning. http://www.bbc.co.uk/dna/h2g2/A4350755.

  8. Ramsland, K. The first forensic science. http://trutv.com/​library/crime/criminal_mind/​forensics/toxicology​/2.html.

Organization of the
Clinical Toxicology
Laboratory

2

This chapter deals with the organization of the complex central clinical laboratories. It deals w...

Table of contents

• Cover
• Title Page
• Copyright
• Dedication
• Contents
• Preface
• Acknowledgments
• Disclaimer
• The Author
• 1: Historical Perspectives in Toxicology
• 2: Organization of the Clinical Toxicology Laboratory
• 3: Unexpected and Unusual Results; Unusual Requests
• 4: Serum/Blood Ethanol
• 5: Ethylene Glycol
• 6: Drug Screens
• 7: Plant Toxins
• 8: Animal Toxins
• 9: U.S. Legal System
• 10: Toxicology Report
• 11: Deposition Testimony
• 12: Court Testimony
• 13: Alcohol Intoxication
• 14: False-Positive Blood Alcohol
• 15: Alcohol and Drugs
• 16: Breathalyzer Tests
• 17: Dram Shop Liability
• 18: Test for Recent Alcohol Use
• 19: Drug Overdose
• 20: Toxic Torts
• 21: Workers’ Compensation
• Index