Forensic Science: Fundamentals & Investigations, Chapter 9 1 Chapter 9 Drug Identification and Toxicology By the end of this chapter you will be able to:

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


Introduction Introduction

Forensic toxicology helps determine cause-and-effect relationships between

o Exposure to a drug or other substance

and o Toxic or lethal effects from that exposure o Toxicology is the study of poisons and the

identification of drugs.• Medicinal, Recreational or Criminal purpose


Introduction Introduction

Toxicity – deals with degree substance is poison or can cause injury.

People can be exposed to toxic substances: o intentionally—

by treating illness or relieving pain o accidentally—

by harmful combinations or overdoses o deliberately—

by harming or killing others, or by suicide

History

o Socrates – 399 B.C. (hemlock)o 17th Century (1600’s) – Rich and famous

• Arsenic and cyanide

o 18th Century (1700’s) – chemical analysis available• Orfila and Christison (M.D.’s)



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


Controlled Substances

Legal drugs – sale and possession are restricted (potential for abuse)

1. Hallucinogens

2. Narcotics

3. Stimulants

4. Anabolic steroids

5. Depressants

Know the charts on pages 254 and 25


Controlled Substances—Hallucinogens

o Often derived from plantso 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



o Affects of an overdose often include • Increased heart rate • Increased blood pressure• Panic attacks, anxiety, or psychosis




Controlled Substances—Narcotics


Controlled Substances—Stimulants

o Increases feelings of energy and alertness

o Suppresses appetiteo Afterwards, depression often resultso Overdose affects include high blood

pressure, agitation, confusion, seizureso Stimulants tend to be highly addictive


Controlled Substances—Stimulants


Controlled Substances—Anabolic Steroids

o A chemical structure similar to testosteroneo Promote cell and tissue growth increasing bone

mass and body muscle. o Popular with weightlifters, bodybuilders, and

other athleteso What are some of the negative side effects?


Controlled Substances—Depressants

o Affects the central nervous system by increasing GABA activity, a neurotransmitter

o Increased GABA causes drowsiness and slowed brain activity

o Relieves anxiety and produces sleepo Side effects include slurred speech and loss of

coordinationo Mixing depressants with alcohol and other drugs

increases potency and health risks


Controlled Substances—Alcohols

o In what way are alcohols toxic?

• Acetaldehyde…..acetic acid……hangover symptomso How is grain alcohol produced?

• Fermentation of sugar in fruits and grainso What are the classic symptoms of a hangover?

• Dehydration, nausea, headache, weaknesso What is the effect of alcohol on the central nervous system?

• Depression o What can chronic alcohol abuse cause?

• Liver damage and dangerous behavior


Controlled Substances—Bacterial Toxins

o Tetanus (also called Lockjaw)• Produced by the Clostridium tetani bacteria • Causes violent muscle spasms

o Botulism • Produced by Clostridium botulinum—botulism • Paralyzes muscles – painful spasms• Causes irreversible damage to nerve endings• Extremely deadly in very small amounts• Most poisonous biological substance


Controlled Substances—Pesticides and Heavy Metals


Controlled Substances—Pesticides and Heavy Metals


Controlled Substances—Bioterrorism Agents

Ricin o A poisonous protein in the castor bean o Lethal in extremely small amountso 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


Controlled Substances—Bioterrorism Agents

Anthrax o Bacillus anthracis, which forms endosporeso 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


. . . . . . . . . Summary. . . . . . . . . . . . . . . . . Summary. . . . . . . .

o Forensic toxicology seeks to identify poisons or drugs in criminals and victims.

o Toxicology is important in studying cases of drug overdose and sporting violations.


. . . . . . . . . . . . . Summary. . . . . . . . . . . . . . . . . Summary. . . .

o Controlled substances fall into five main groups:• Hallucinogens • Narcotic• Stimulants• Steroids• Depressants


. . . . . . . . . . . . . . . . . Summary. . . . . . . . . . . . . . . . . Summary

o Poisons can be produced by living organisms.

o Pesticides and heavy metals are common poisons.

o Bioterrorism agents include ricin and anthrax.

Documents

Forensic Science: Fundamentals & Investigations, Chapter 9 1 Chapter 9 Drug Identification and Toxicology By the end of this chapter you will be able to: