Presentation is loading. Please wait.

Presentation is loading. Please wait.

Forensic Science: Fundamentals & Investigations, 2e Chapter 9 1 All rights Reserved Cengage/NGL/South-Western © 2016.

Similar presentations


Presentation on theme: "Forensic Science: Fundamentals & Investigations, 2e Chapter 9 1 All rights Reserved Cengage/NGL/South-Western © 2016."— Presentation transcript:

1 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 1 All rights Reserved Cengage/NGL/South-Western © 2016

2 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Chapter 9 Forensic Toxicology By the end of this chapter you will be able to: 9.1 Provide examples of drugs, poisons, and toxins. 9.2 List factors that affect drug toxicity. 9.3 Describe the role of a toxicologist in analyzing substance evidence. 9.4 Compare and contrast presumptive testing and confirmatory testing. 2

3 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Chapter 9 Forensic Toxicology By the end of this chapter you will be able to: 9.5 Describe how people get exposed to environmental toxins (e.g., pesticides, carbon monoxide), and describe their effects on the body. 9.6 Distinguish among the terms tolerance, addiction, dependence, and withdrawal. 9.7 Relate the signs and symptoms of overdose with a specific substance or combination of substances. 9.8 Show the relationships between the law, crime, and the use of drugs. 3

4 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 o addiction o controlled substance o Controlled Substances Act o dependency o depressant o hallucinogen o illegal drug 4 Chapter 9 Vocabulary o narcotic o poison o stimulant o tolerance o toxicity o toxicology o toxin

5 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Introduction o Toxicology is the study of substances that can harm a person. Poisons Toxins o A person may be exposed to a substance in any of the ways below: Intentionally Accidentally Deliberately 5

6 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Brief History of Forensic Toxicology o Socrates is one of the earliest reported victims of poisoning (Hemlock, 399 B.C. ) o By the 1600s, poisoning had become a profession. o During the 1800s, methods of chemical analysis were developed to identify poisons. o In 1980, standardized techniques and testing were developed to help determine the cause of death. 6

7 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Brief History of Forensic Toxicology (continued) o In 1959, the FDA was formed. o In 1970, Congress passed the Controlled Substances Act. o Today, less than one-half of one percent of all homicides result from poisoning. 7

8 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Brief History of Forensic Toxicology (continued) o In 1978, Bulgarian dissident Georgi Markov was stabbed in the leg with an umbrella armed with a ricin toxin. 8

9 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Evidence Detection, Collection, and Storage 9 o Evidence may be in the form of: Pills, powders, liquids Botanical matter (seeds, leaves, mushrooms) Crystals (methamphetamine) Evidence found on clothing, objects, or liquid soaked fabrics Urine, blood, sweat, or saliva o Correct packaging of the evidence is important to preserve the evidence and to protect individuals working with the evidence.

10 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Evidence Testing and Reporting of Drugs, Poisons and Toxins o A toxicologist needs to answer three basic questions: 1.What substances are there? (qualitative testing) 2.Might there be any illegal components? 3.How much of each substance is present? (quantitative testing) o Presumptive testing may be performed at the crime scene. 10

11 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Evidence Testing and Reporting of Drugs, Poisons and Toxins (continued) o Confirmatory testing is a multistep process that provides a positive identification of the substance. o Toxicologists must also distinguish between: Acute poisoning Chronic poisoning 11

12 All rights Reserved Cengage/NGL/South-Western © 2016 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 12

13 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Heavy Metals, Gases, Poisons, and Toxins 13

14 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Lethal Gases and Lethal Injections o Lethal gas chambers Nazis during World War II Carbon monoxide from engine exhaust and hydrogen cyanide o American penal systems Hydrogen cyanide o Carbon monoxide gas o Injections of potassium chloride or sodium pentothal 14

15 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Pesticides and Herbicides 15

16 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Toxins 16 o Toxins may be produced by plants or animals. Ricin Rattlesnake venom

17 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Drugs and Crime o Almost half of the individuals in federal prisons are there because of drug-related offenses. o More than $600 billion is spent annually on costs related to crime, lost work productivity, and healthcare because of drug abuse. o Continued use of a drug can lead to addiction and dependency. 17

18 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Five Schedules of Drugs o Schedule I No medical use, high potential for abuse Ex: Heroine, LSD, peyote, MDMA, bath salts o Schedule II Severely restricted medical use, high potential for abuse Ex: Cocaine, methamphetamine, methadone, oxycodone o Schedule III Accepted medical use, moderate potential for abuse, moderate to low risk of dependence Ex: Barbiturates, steroids, ketamine 18

19 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Five Schedules of Drugs (continued) o Schedule IV Medical use, low potential for abuse and the risk of dependency Ex: Xanax, Valium, sleeping pills, other tranquilizers o Schedule V Widely used for medical purposes, very low potential for abuse, contains limited quantities of narcotics Ex: Robitussin ® AC, Tylenol ® with codeine 19

20 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Illegal Drugs 20 o Hallucinogens Affect perception, thinking, self-awareness, and emotions Flashbacks may occur long after the drugs wear off o Heroine Narcotics are addictive, sleep inducing drugs that act as central nervous system depressants and suppress pain. Highly addictive o Combining drugs, such as heroin and alcohol, can be fatal.

21 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Illegal Drugs (continued) 21

22 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Controlled Substances o Stimulants o Narcotics o Depressants 22

23 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Alcohol 23 o Alcohol is a central nervous system depressant. o The amount of alcohol in a beverage is expressed as a percentage by volume or in proof, which is twice the percentage. o A liquor that is 80 proof contains 40% alcohol. o Someone with a blood alcohol concentration of.15 percent will retain alcohol in his or her body for approximately 10 hours.

24 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 Anabolic Steroids o Anabolic steroids promote cell and tissue growth and division. They have a chemical structure similar to testosterone. o Negative side effects may include: Acne, increased body hair, and baldness Increased aggression, high blood pressure, high cholesterol levels, impaired fertility in males, blood clotting, kidney and liver cancers, and heart attacks 24

25 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 o Toxicology is the study of poisons, toxins, drugs, and other substances a person may use for medical, recreational, or criminal purposes. Forensic toxicologists study the harmful effects of these substances on the body, typically after a death. o The toxicity of a substance depends on the dose, the duration of exposure, the nature of exposure, interactions with other substances, and the byproducts formed when metabolized. 25 Summary

26 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 o Exposure to heavy metals, poison gases, other poisons, toxins, or radiation may occur accidentally or as a result of a crime (or punishment) and have harmful or lethal effects on the body. o Drugs are classified by their effect on the body as stimulants, depressants, narcotics, hallucinogens, or anabolic steroids; drugs are classified under five schedules created by the 1970 Controlled Substances Act. 26 Summary (continued)

27 Forensic Science: Fundamentals & Investigations, 2e Chapter 9 All rights Reserved Cengage/NGL/South-Western © 2016 o Use of drugs can affect a person’s health, mood, awareness, metabolism, and/or perception of reality. o Extended exposure to drugs can lead to tolerance, dependence, addiction, and illness. o Drug combinations can have compounding effects and result in accidental death. 27 Summary (continued)


Download ppt "Forensic Science: Fundamentals & Investigations, 2e Chapter 9 1 All rights Reserved Cengage/NGL/South-Western © 2016."

Similar presentations


Ads by Google