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Chapter 9 Drug Identification
and Toxicology
By the end of this chapter you will be able to:
 identify the five types of controlled substances
 relate signs and symptoms of overdose with a
specific class of drugs or toxins
 describe the role of various types of toxins in
causing death
 discuss agents that may be used in bioterrorism
 define and describe the goals and practice of
toxicology
All Rights Reserved South-Western / Cengage Learning © 2009
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Forensic Science: Fundamentals & Investigations, Chapter 9
Introduction
Forensic toxicology helps determine (a) the cause-andeffect relationships between exposure to a drug or other
substance and (b) the toxic or lethal effects from that
exposure.
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
committing suicide
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Forensic Science: Fundamentals & Investigations, Chapter 9
Poison—Murder, Accidental
Overdoses,
and Drug Offences
 Less than ½ of 1% of all homicides results
from poisoning.
 Accidental drug overdoses are more
common.
 More than 50% of the federal prison
population and about 20% of the population
in state prisons consist of drug offenders.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Hallucinogens
 The effect and intensity of response to these
drugs varies from person to person.
 Often derived from plants, hallucinogens
affect the user’s perceptions, thinking, selfawareness, and emotions.
 Affects of an overdose include an increased
heart rate, often increased blood pressure,
and sometimes panic attacks, anxiety, or
psychosis.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Narcotics
Narcotics reduce pain and can be very habit forming.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Stimulants
 Stimulants increase feelings of energy
and alertness while suppressing appetite.
 As the drug wears off, however,
depression often results.
 Affects of an overdose can include high
blood pressure, agitation, confusion, or
seizures.
 Stimulants tend to be highly addictive.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Anabolic
Steroids

These drugs are produced in a laboratory and
have a chemical structure similar to
testosterone.
 Anabolic steroids promote cell and tissue
growth increasing bone mass and body
muscle.
 Because of this they are popular with
weightlifters, bodybuilders, and other athletes.
 What are some of the negative side effects that
are possible?
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Depressants

Depressants act on the central nervous system
and increase the activity of a neurotransmitter
called GABA.
 Increased GABA production results in
drowsiness and slowed brain activity.
 These drugs, consequently, relieve anxiety and
produce sleep.
 Mixing depressants with alcohol and other
drugs increases their effects and health risks,
possibly leading to coma and death.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Alcohols
 In what way are alcohols toxic?
 How is grain alcohol produced?
 What are the classic symptoms of a
hangover?
 What is the effect of alcohol on the central
nervous system?
 What can chronic abuse of alcohol cause?
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Bacterial
Toxins
Tetanus
 Lockjaw, as it is sometimes called, is produced by
the Clostridium tetani bacteria.
 Its poison can cause violent muscle spasms.
Botulism
 Produced by the bacteria Clostridium botulinum,
botulism paralyzes muscles.
 It causes irreversible damage to nerve endings.
 Very small amounts are extremely deadly.
 Botulism is the most poisonous biological substance.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Pesticides and
Heavy Metals
Pesticides mostly are used to protect plants or food crops.
Metal compounds are very poisonous.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Pesticides and
Heavy Metals
Metal compounds can damage many organs in the body.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Bioterrorism
Agents
Ricin
 is a poisonous protein in the castor bean.
 is lethal in extremely small amounts.
 can enter the body in various ways:
– inhaled as a mist or a powder.
– ingested as food or drink.
– injected into the body.
 can cause death within a few hours.
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Forensic Science: Fundamentals & Investigations, Chapter 9
Controlled Substances—Bioterrorism
Agents
Anthrax
 is caused by the bacteria Bacillus anthracis, which
forms spores.
 can be spread to humans from infected animals.
 can enter 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.
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Forensic Science: Fundamentals & Investigations, Chapter 9