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Chapter 9: Drugs Forensic Science.

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Presentation on theme: "Chapter 9: Drugs Forensic Science."— Presentation transcript:

1 Chapter 9: Drugs Forensic Science

2 What is a Drug? Any natural or synthetic substance that is used to produce physiological or psychological effects on humans or animals.

3 Drugs used to be associated mostly with those belonging to the lower socioeconomic classes but now it is an issue spanning across all socioeconomic and ethnic classes of society. 23 million people in the U.S. are users of elicit drugs 90 million people in the U.S. drink alcohol regularly (10 million are alcoholics) .

4 Drug Dependence First drugs to be controlled by law were the one’s deemed “habit-forming” (opium, cocaine and marijuana) Two types of dependence: Physical: serious physical effects felt when the drug use is discontinued abruptly Psychological: drug use is needed for the “emotional well-being” of the user. No physical effects are felt when discontinuing use.

5 The common denominator that characterizes all types of repeated drug use is the creation of a psychological dependence for continued use of the drug.

6 More on Drugs… More than 75% of evidence evaluated in the crime laboratories is drug related Drug use alone has supported the expansion and creation of crime laboratories

7 Narcotic: Pain-killing substances that depress bodily functions (blood pressure, pulse and breathing rate)

8 Analgesic: A drug or substance that lessens or eliminates pain.

9 Hallucinogen: Induces in changes in mood, attitude, thought or perception

10 Depressant Substance that depresses the functions of the central nervous system. Can calm irritability and anxiety and may induce sleep.

11 Stimulant Substance taken to increase alertness or activity.

12 Stimulant Side Effects:
Initial “rush” sensation followed by intense feeling of pleasure. Can cause hyperactivity, clarity of vision and hallucinations. After use can cause period of exhaustion and/or depression.

13 Depressant Side Effects:
Affect judgment, memory and concentrations. Reduces coordination Slow reaction time Highly irritable or emotional

14 For the table on #7, please add “Narcotic” as a choice to the first column.

15 Narcotics Pain-killing substances that depress bodily functions (blood pressure, pulse and breathing rate) A.K.A. analgesics Most are derived from opium: milky juice obtained from the unripe pod of the poppy Examples: Codeine, Heroin, Oxycontin, Methadone Psychological and Physical dependence

16 Hallucinogens Induces in changes in mood, attitude, thought or perception Cannabis (Marijuana) Used for over 3,000 years, but brought to U.S. in 1920 by Mexican laborers In 1937, 46 states and federal government deemed it “illegal”

17 Hallucinogens, cont’d Psychological dependence develops in the heavy user Effects: red eyes, impaired motor skills and concentration, frequent hunger Possible medical uses include: reduction of eye pressure in glaucoma, decrease in nausea for anti-cancer drugs and muscle relaxant (#10 on Reading Guide)

18 Hallucinogens, cont’d Others include: LSD, PCP, ecstasy
LSD: very potent drug that causes visual hallucinations that can last up to 12 hours. Produces marked changes in behavior. Feelings of anxiety and tension accompany use. User can be prone to flashbacks and psychotic reactions even after use is discontinued. Low psychological dependence

19 Hallucinogens, cont’d PCP: users experiences feelings of strength and invulnerability, along with a sense of detachment. User soon becomes unresponsive, confused and agitated. Depression, irritability, feelings of isolation, audio and visual hallucinations and paranoia are experience by the user.

20 Depressants Depresses the functions of the nervous system
Calm irritability and anxiety and can induce sleep Examples include: alcohol, barbiturates, tranquilizers, glue sniffing (huffing) Psychological and physical dependence

21 Please listen to the following, you can chose to add some of this information if you would like

22 Barbiturates Known as “downers”
25 derivatives used in medical practice in U.S. Can be long-acting or fast-acting: depending on how long it takes for the effects to take place Fast-acting: secobarbital, pentobarbital, and amobarbital Long-acting: phenobarbital Non-barbiturate depressant: methaqualone

23 Tranquilizers Relax the body without impairing the higher-thinking abilities and inducing sleep Studies show physical and psychological dependence on tranquilizers with repeated use Some commonly prescribed tranquilizers include: miltown, librium, valium

24 Glue-Sniffing/Huffing
Generally, toluene-based substances are used Causes slurred speech, impaired judgement and double vision, drowsiness and stupor High risk of death Damages liver, heart and brain

25 Stimulants Increases alertness or activity
Includes: amphetamines, cocaine, ecstasy, LSD, PCP, GHB and Rohypnol

26 Amphetamines Synthetic drugs Known as uppers or speed
Generally taken orally, however, can be injected (methamphetamine) or smoked (ice) Causes decrease in fatigue and loss of appetite Apprehension and depression may follow after it wears off

27 Cocaine Derived from the coca plant by Sigmund Freud
Derivatives such as lidocaine and procaine used for medical local pain-killers Generally sniffed or snorted Can be smoked in crystal form (crack) No physical dependency, however, creates the strongest psychological dependency of commonly used drugs

28 Club Drugs Synthetic drugs that got their names from use at nightclubs, raves and bars Includes Ecstasy, LSD, PCP, GHB and Rohypnol (#8 on reading guide) GHB an Rohypnol commonly used in sexual assault, rape and robbery due to the loss of memory while on drug Leads to relaxation, loss of consciousness and an inability to remember what happened during the hours after ingesting.

29 Anabolic Steroids Related to testosterone
Promotes male characteristics and accelerates muscle growth Generally taken by athletes to increase performance Causes liver cancer and liver malfunctions, masculine features in women, decreased sex drive in men and infertility Mild physical dependence

30 Alcohol is the most widely used and abused drug.
Why? Legal to purchase over the age of 21 in the US and easy access. In the US, the alcohol industry produced more than one billion gallons of spirits, wine and beer for which 90 million consumers pay nearly $40 billion.

31 Marijuana is the most widely used and abused illicit drug.
Illegal to purchase and/or consume in the US.

32 Controlled Substances Act
Creates a method of organizing drugs by their potential for abuse, potential for dependence and medical value. Very flexible in that the U.S. Attorney General has the ability to add, delete or reschedule drugs as more information is obtained Serves to create uniform drug laws across the U.S. Penalties for unauthorized sale, manufacture or distribution are related to the schedules

33 Schedules for the Controlled Substances Act
Schedule I: high potential for abuse, no medical use (heroin, marijuana, methaqualone & LSD) Schedule II: high potential for abuse, have accepted medical use with severe restrictions. High potential for dependence (opium and derivatives, cocaine, PCP, amphetamines, barbiturates)

34 Schedules for the Controlled Substances Act, cont’d
Schedule III: less potential for abuse, accepted medical use and low-moderate physical but high psychological dependence (anabolic steroids, some barbiturates and some codeines) Schedule IV: low potential for abuse, current medical use and limited dependence (Darvon, Valiu, Librium) Schedule V: low potential for abuse, current medical use and less dependence compared to schedule IV (opiate mixtures and non-narcotic medicinal ingredients)

35 The most severe penalties are for Schedule I and II drugs.

36 Drug Identification Difficulty is determining the analytical technique to use which will ensure a specific identification of the drug. Use two phases: Screening phase and the Confirmation phase (#17 on reading guide) Screening phase: Reduce the possible identity of the drug down to a manageable number Confirmation phase: Specifically identifies the drug

37 Color Tests Screening phase test
Use specific reagents to create a presence or absence of color when in contact with drug Marquis: reagent turns purple when in contact with heroin and morphine and opium derivatives. Orange brown when mixed with amphetamines.

38 Color Tests, cont’d Dillie-Koppanyi: turns violet-blue in presence of barbiturates Dequenois-Levine: Purple color in presence of marijuana Van Urk: blue-purple when in contact with LSD Scott test: color test for cocaine. Series of tests; blue  pink  blue again

39 Microcrystalline Tests
Identifies specific substances by color and morphology of the crystals formed Drop of chemical reagent is added to substance on a microscope slide, chemical reaction occurs resulting in a crystalline precipitate. The microscope is then used to analyze the size and shape of the crystals. Rapid test and the drug does not have to be pure

40 Chromatography TLC and Gas Chromatography are used to separate the drug from its diluents Can provide tentative results Analyst must have idea as to the identity of the drug before using these techniques With GC-Mass spec a scientist can purify and POSITIVELY identify a substance in one step

41 Spectrophotometry UV-Spec doesn’t provide positive identification, but can provide a PROBABLE identity IR-Spec provides a POSITIVE identification Substance must be purified, which can be a lengthy process

42 Collection and Preservation of Drug Evidence
Must be properly packaged and labeled Common sense is generally the best guyde Package must prevent loss of sample and cross-contamination of substance Volatile substances (such as in glue-sniffing cases) must be placed in an air-tight container Label must include sufficient information as to establish chain-of-custody Supply any background information on the drug if possible


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