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Forensic Science: Fundamentals & Investigations, Chapter 9 1
Chapter 9 Drug Identification and Toxicology By the end of this chapter you will be able to:
o Identify the five types of controlled substances
o Relate signs and symptoms of overdose with a specific class of drugs or toxins
o Describe the role of various types of toxins in causing death
o Discuss agents that may be used in bioterrorism
o Define and describe the goals and practice of toxicology
All Rights Reserved South-Western / Cengage Learning © 2012, 2009
Forensic Science: Fundamentals & Investigations, Chapter 9 2
Introduction
Forensic toxicology helps determine cause-and-effect relationships between:
• Exposure to a drug or other substance
• Toxic or lethal effects from that exposure
Forensic Science: Fundamentals & Investigations, Chapter 9 3
Introduction
People can be exposed to toxic substances:
• Intentionally—by treating illness or relieving pain
• Accidentally—by harmful combinations or overdoses
• Deliberately—by harming or killing others, or by suicide
Forensic Science: Fundamentals & Investigations, Chapter 9 4
Poison—Murder, Accidental Overdoses, and Drug Offences
o Poisoning causes less than ½ of 1% of all homicides
o Accidental drug overdoses are more common
o Drug offenders
• More than 50% of the federal prison population
• About 20% of the population in state prisons
Forensic Science: Fundamentals & Investigations, Chapter 9 5
Controlled Substances
1. Hallucinogens
2. Narcotics
3. Stimulants
4. Anabolic steroids
5. Depressants
Forensic Science: Fundamentals & Investigations, Chapter 9 6
Controlled Substances —Hallucinogens
o Often derived from plants
o The effect and intensity of response to these drugs varies from person to person.
o Affects the user’s perceptions, thinking, self-awareness, and emotions
Forensic Science: Fundamentals & Investigations, Chapter 9 7
Controlled Substances —Hallucinogens
Notice any
common
overdoses
symptom(s)?
Forensic Science: Fundamentals & Investigations, Chapter 9 8
Controlled Substances —Hallucinogens
o Affects of an overdose often include
• Increased heart rate
• Increased blood pressure
• Panic attacks, anxiety, or psychosis
Forensic Science: Fundamentals & Investigations, Chapter 9 9
Controlled Substances —Narcotics
o Reduce pain by suppressing pain receptors in the central nervous system
o Often referred to as pain killers
o Affects the user’s perceptions, thinking, self-awareness, and emotions
Forensic Science: Fundamentals & Investigations, Chapter 9 10
Controlled Substances —Narcotics
Forensic Science: Fundamentals & Investigations, Chapter 9 11
Controlled Substances —Stimulants
o Increases feelings of energy and alertness
o Suppresses appetite
o Afterwards, depression often results
o Overdose affects include high blood pressure, agitation, confusion, seizures
o Stimulants tend to be highly addictive
Forensic Science: Fundamentals & Investigations, Chapter 9 12
Controlled Substances —Stimulants
Forensic Science: Fundamentals & Investigations, Chapter 9 13
Controlled Substances —Anabolic Steroids
o A chemical structure similar to testosterone
o Promote cell and tissue growth increasing bone mass and body muscle.
o Popular with weightlifters, bodybuilders, and other athletes
o What are some of the negative side effects?
Forensic Science: Fundamentals & Investigations, Chapter 9 14
Controlled Substances —Depressants
o Affects the central nervous system by increasing the activity of the neurotransmitter GABA
o Increased GABA causes drowsiness and slowed brain activity
o Relieves anxiety and produces sleep
o Side effects include slurred speech and loss of coordination
o Mixing depressants with alcohol and other drugs increases potency and health risks
Forensic Science: Fundamentals & Investigations, Chapter 9 15
Controlled Substances —Alcohols
o What are the classic symptoms of a hangover?
o What is the effect of alcohol on the central nervous system?
o What can chronic alcohol abuse cause?
Forensic Science: Fundamentals & Investigations, Chapter 9 16
Controlled Substances —Pesticides and Heavy Metals
Forensic Science: Fundamentals & Investigations, Chapter 9 17
Controlled Substances —Pesticides and Heavy Metals
Forensic Science: Fundamentals & Investigations, Chapter 9 18
Controlled Substances —Bioterrorism Agents
Ricin o A poisonous protein in the castor bean
o Lethal in extremely small amounts
o Enters the body in various ways: • inhaled as a mist or a powder
• ingested as food or drink
• injected into the body
o Causes death within a few hours
Forensic Science: Fundamentals & Investigations, Chapter 9 19
Controlled Substances—Bioterrorism Agents
Anthrax o Bacillus anthracis, which forms endospores
o Spreads to humans from infected animals
o Enters the human body through:
• Inhalation; causing breathing problems that usually result in death
• Ingestion; becoming fatal in 25% to 60% of cases
• Absorption via the skin; leading to death in about 20% of untreated cases
