Transcript Introduction

Chapter 9
Drug Identification and Toxicology
By the end of this chapter you will be able to:
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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
Introduction
TOXICOLOGY
the study of poisons and the identification of drugs
1. Medicinal
2. Recreational
3. Criminal
*ingesting, inhaling, injecting
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Introduction
TOXICITY
The degree to which a substance is poisonous
or can cause injury
 Use (how it was taken)
 Duration (frequency)
 Nature of exposure (ingested, inhaled or absorbed)
 Interaction (mixture with other drugs)
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Introduction
Forensic toxicology helps determine causeand-effect relationships
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Exposure to a drug or other substance
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Toxic or lethal effects from that exposure
Introduction
People can be exposed to toxic substances:
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intentionally—
by treating illness or relieving pain
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accidentally—
by harmful combinations or overdoses
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deliberately—
by harming or killing others, or by suicide
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Brief History of Drugs
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399 BC - Socrates died of hemlock poisoning
Arsenic poisoning “inheritance powder”
1797 – Orfila and Christison could identify arsenic in
the tissue of bodies
1945 – cyanide capsules used to murder Nazi
leaders Himmler and Goering
1978 – Jonestown cult members (cyanide punch
killing 900 people)
1978 – Bulgarian dissident Markov died by ingesting
ricin, a component of the waste product of the
manufacture of castor oil from castor bean
Poison
Commonly used poisons
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Arsenic
Cyanide
Strychnine
Chemicals used in fertilizer
Others
Acute poisoning – high dose over a short period of time, such as
cyanide ingestion or inhalation, immediately producing symptoms
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Chronic poisoning – lower doses over longer periods of time, gradual
symptoms
Poison—Murder, Accidental
Overdoses, and Drug Offences
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Poisoning causes less than ½ of 1% of all
homicides (not common)
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Accidental drug overdoses are more common
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Drug offenders
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More than 50% of the federal prison population
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About 20% of the population in state prisons
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Arrests have increased since the early 1900’s
Controlled Substances
Legal drugs whose sale, possession, and use are restricted
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Hallucinogens
Narcotics
Stimulants
Anabolic steroids
Depressants
Controlled Substances
—Hallucinogens
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Often derived from plants
The effect and intensity of response to these
drugs varies from person to person.
Affects the user’s perceptions, thinking, selfawareness, and emotions
Controlled Substances
—Hallucinogens
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Affects of an overdose often include
• Increased heart rate
• Increased blood pressure
• Panic attacks, anxiety, or psychosis
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Controlled Substances
—Hallucinogens
LSD – found in 1938 in a fungus that grows on grains, most potent mood changing.
Odorless,
colorless and tasteless. Sold in tablets, absorbent paper divided into decorative squares.
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PCP – pure, white, crystal powder, a tablet or capsule.
Controlled Substances
—Narcotics
Used to reduce pain by suppressing the central nervous
system…often causes unconsciousness
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Controlled Substances
—Stimulants
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Increases feelings of energy and
alertness
Suppresses appetite
Afterwards, depression often results
Overdose affects include high blood
pressure, agitation, confusion, seizures
Stimulants tend to be highly addictive
Controlled Substances
—Stimulants
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Controlled Substances
—Anabolic Steroids
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A chemical structure similar to testosterone
Promote cell and tissue growth increasing bone
mass and body muscle.
Popular with weightlifters, bodybuilders, and
other athletes
What are some of the negative side effects?
Controlled Substances
—Depressants
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Barbiturates and benzodiazepines
Affects the central nervous system by increasing
GABA activity, a neurotransmitter
Increased GABA causes drowsiness and slowed
brain activity
Relieves anxiety and produces sleep
Side effects include slurred speech and loss of
coordination
Mixing depressants with alcohol and other drugs
increases potency and health risks
Controlled Substances
—Alcohols
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In what way are alcohols toxic?
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How is grain alcohol produced?
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What are the classic symptoms of a
hangover?
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What is the effect of alcohol on the central
nervous system?
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What can chronic alcohol abuse cause?
Controlled Substances
—Bacterial Toxins
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Tetanus (also called Lockjaw)
• Produced by the Clostridium tetani bacteria
• Causes violent muscle spasms
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Botulism
• Produced by Clostridium botulinum—botulism
• Paralyzes muscles
• Causes irreversible damage to nerve endings
• Extremely deadly in very small amounts
• Most poisonous biological substance
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Toxins
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Organic - poisonous substances produced by
living organisms. (bee sting, snake bite, plants)
Alcohols – ethanol (beverages)
Bacterial – EX. Botulism is the most poisonous
- (Clostridium botulinum)
- contaminated foods
EX. Tetanus – deadly
- (Clostridium tetani)
Controlled Substances
—Pesticides and Heavy Metals
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Controlled Substances
—Pesticides and Heavy Metals
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Controlled Substances
—Bioterrorism Agents
Ricin
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A poisonous protein in the castor bean
Lethal in extremely small amounts
Enters the body in various ways:
• inhaled as a mist or a powder
• ingested as food or drink
• injected into the body
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Causes death within a few hours
Controlled Substances—Bioterrorism
Agents
Anthrax
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Bacillus anthracis, which forms endospores
Spreads to humans from infected animals
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
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. . . . . . . . . Summary. . . . . . . .
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Forensic toxicology seeks to identify poisons
or drugs in criminals and victims.
Toxicology is important in studying cases of
drug overdose and sporting violations.
. . . . . . . . . . . . . Summary. . . .
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Controlled substances fall into five main
groups:
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Hallucinogens
Narcotic
Stimulants
Steroids
Depressants
. . . . . . . . . . . . . . . . . Summary
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Poisons can be produced by living
organisms.
Pesticides and heavy metals are common
poisons.
Bioterrorism agents include ricin and anthrax.