Transcript Slide 1

Drugs
Drugs
Objectives
You will understand:
How to apply deductive reasoning to a
series of analytical data.
The limitations of presumptive
(screening) tests.
The relationship between the
electromagnetic spectrum and
spectroscopic analysis.
The dangers of using prescription
drugs, controlled substances, overthe-counter medications, and illegal
drugs.
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Drugs
Objectives, continued
You will be able to:
Chemically identify illicit drug types.
Classify the types of illicit drugs and their
negative effects.
Discuss the federal penalties for
possession and use of controlled
substances.
Explain the need for confirmatory tests.
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Drugs
Objectives, continued
You will be able to:
Describe IR, UV-VIS spectroscopy, and GCMS.
Present and interpret data with graphs.
Use the Physicians’ Desk Reference (PDR)
to identify pills.
Use technology and mathematics to improve
investigations and communications.
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Drugs
Drugs and Crime
A drug is a natural or synthetic substance designed to affect the subject
psychologically or physiologically.
A poison is a drug that shows toxic effects.
“Controlled substances” are drugs that are restricted by law.
The Controlled Substances Act is a law that was enacted in 1970; it lists
illegal drugs, their categories, and penalties for possession, sale, or
use.
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Drugs
Why do we care?
The Office of National Drug Control Policy estimates that illegal drug use costs
society $110 billion a year. Drug-related violence and crime also pose a grave and
much more direct threat to the United States. According to the 1999 Arrestee
Drug Abuse Monitoring Program, 75% of the male adults arrested in NYC for
committing a violent crime tested positive for drug use. The report also showed
that even in smaller cities, these figures ranged as high as 65%.
The drug epidemic is also taking a toll on the very core of American society -- the
family. Drug use causes violence and abuse within families: One-quarter to onehalf of all incidents of domestic violence are drug related. A survey of state childwelfare agencies found substance abuse to be one of the key problems exhibited
by 81% of the families reported for child neglect and abuse. Additionally, 3.2% of
pregnant women -- nearly 80,000 mothers -- use drugs regularly, which will
affect their babies.
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Drugs
Controlled Substances Act
Schedule I—high potential for abuse; no currently
accepted medical use in the U.S.; a lack of accepted
safety for use under medical supervision
Examples: heroin (diacetylmorphine), LSD, marijuana,
ecstasy (MDMA)
Schedule II—high potential for abuse; a currently
accepted medical use with severe restrictions; abuse
may lead to severe psychological or physical
dependence
Examples: cocaine, morphine, amphetamines (including
methamphetamines), PCP, Ritalin
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Controlled Substances Act, continued
Schedule III—lower potential for abuse than the drugs in I or II; a
currently accepted medical use in the U.S.; abuse may lead to
moderate physical dependence or high psychological dependence
Examples: intermediate-acting barbiturates, anabolic steroids, ketamine
Schedule IV—low potential for abuse relative to drugs in III; a
currently accepted medical use in the U.S.; abuse may lead to
limited physical or psychological dependence relative to drugs
in III
Examples: stimulants and depressants including Valium, Xanax,
Librium, phenobarbital, Darvon
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Drugs
Controlled Substances Act, continued
Schedule V—low potential for abuse relative to drugs in IV; currently
accepted medical use in the U.S.; abuse may lead to limited physical
or psychological dependence relative to drugs in IV
Examples: codeine found in low doses in cough medicines
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Drugs
Illegal or Illicit?
An illegal drug is a drug that is against the law to have, use, or
distribute.
Cocaine
Crack
An illicit drug is a legal drug used in an inappropriate or illegal way.
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Drugs
Classification of Illicit Drugs
 Hallucinogens—induces changes in normal thought processes,
perceptions, and moods (marijuana, LSD, PCP, MDMA/ecstasy,
Ketamine)
 Stimulants—speeds up the CNS (speed, cocaine, club drugs,
anabolic steroids); includes caffeine and nicotine
 Narcotics—a drug that induces sleep and depresses vital body
functions such as blood pressure, pulse rate, and breathing rate
(morphine, heroin, methadone, codeine); analgesics, affect CNS to
relieve pain (aspirin, acetaminophen, ibuprofen)
 Depressants—slows the CNS (alcohol, barbiturates, Valium), often
prescribed to reduce anxiety or as a sleep aid; huffing propellants
and solvents
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Drugs
Identification of Drugs
 PDR—Physicians’ Desk Reference
 Field Tests—presumptive tests
 Laboratory Tests—conclusive
tests
Kendall/Hunt Publishing
Company
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Drugs
Physicians’ Desk Reference
PDR—A Physicians’ Desk Reference is
used to identify manufactured pills,
tablets, and capsules. It is updated each
year. This can sometimes be a quick and
easy identifier of the legally made drugs
that may be found at a scene. The
reference book gives a picture of the drug
and states whether it is prescription, overthe-counter, or a controlled substance; it
gives more detailed information about the
drug as well.
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Drugs
Human Components Used for Drug Analysis
Blood
Liver tissue
Urine
Brain tissue
Hair
Kidney tissue
Gastric contents
Spleen tissue
Bile
Vitreous humor of the eye
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Drugs
Forensic Drug Analysis and
Identification
Forensic Chemist must have a plan of action
1. Screening or presumptive
tests
2. Confirmatory tests (test
that specifically identifies a
substance)
(used to reduce the number of
possible identities of an unknown substance)
 Spot or color tests
 Microcrystalline test—
a reagent is added that produces
a crystalline precipitate which is
unique for a certain drug.
 Chromatography


Spectrophotometry
 Ultraviolet (UV)
 Visible
 Infrared (IR)
Mass spectrometry
Qualitative determine what is in
a mixture
Quantitative determine the %
combination of components in
the mixture
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Drugs
Drug Identification, continued
Screening or presumptive tests only tell that the drug is possibly present.
Confirmatory tests tell that the drug is positively present.
(Screening tests are easier, cheaper, and quicker to use.)
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Presumptive Color Tests
Marquis—turns purple in the presence of
most opium derivatives and orange-brown
with amphetamines
Dille-Koppanyi—turns violet-blue in the
presence of barbiturates
Duquenois-Levine—turns a purple color in
the presence of marijuana
Van Urk—turns a blue-purple in the
presence of LSD
Scott test—color test for cocaine; blue
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Drugs
Presumptive Color Tests
Drug
Marijuana
LSD
Amphetamines
Cocaine
Heroin
Barbiturates
Reagent
Duquenois-Levine (D-L)
Erlich/Van Urk (ERL)
Marquis (MARQ)
Cobalt thiocyanate (CO)
Marquis (MARQ)
Dille-Kopanyi (D-K)
Color
Blue-violet
Blue-violet
Red-orange  brown
Blue flaky precipitate
Purple
Violet
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Chromatography
A technique for separating mixtures into their components
Includes two phases—a mobile one that flows past a stationary one
The mixture interacts with the stationary phase and separates
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Types of Chromatography
Paper
Thin-layer (TLC)
Gas (GC)
Pyrolysis gas (PGC)
Liquid (LC)
High-performance liquid (HPLC)
Column
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Paper Chromatography
Stationary phase—paper
Mobile phase—a liquid solvent
Capillary action moves the mobile
phase through the stationary phase.
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Retention Factor (Rf)
This is a number that represents how
far a compound travels in a
particular solvent.
It is determined by measuring the
distance the compound traveled
and dividing it by the distance the
solvent traveled.
If the Rf value for an unknown
compound is close to or the same
as that for the known compound,
the two compounds are likely
similar or identical (a match).
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Drugs
Thin Layer Chromatography
Click on Chapter
5 Drugs, and go
to Web Extras
 Stationary phase—
a thin layer of coating
(usually alumina or
silica) on a sheet of
plastic or glass
 Mobile phase—
a liquid solvent
Watch animated depictions of Thin-Layer Chromatography and
Gas Chromatography at www.prenhall.com/hsforensics
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Drugs
Gas Chromatography
Phases
Stationary—a solid or a
viscous liquid that lines a tube
or column
Mobile—an inert gas like
nitrogen or helium
Analysis
Shows a peak that is
proportional to the quantity of
the substance present
Uses retention time instead of Rf for
the qualitative analysis
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Drugs
Uses of Gas Chromatography
Not considered a confirmation of a controlled substance
Used as a separation tool for mass spectroscopy (MS) and infrared
spectroscopy (IR)
Used to quantitatively measure the concentration of a sample. (In a
courtroom, there is no real requirement to know the concentration of
a substance. It does not affect guilt or innocence.)
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Confirmatory Tests: Spectroscopy
Spectroscopy—the interaction of electromagnetic radiation with
matter
Spectrophotometer—an instrument used to measure and record
the absorption spectrum of a chemical substance
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Spectrophotometry
Components
A radiation source
A frequency selector
A sample holder
A detector to convert electromagnetic
radiation into an electrical signal
A recorder to produce a record of the
signal
Types
Ultraviolet
Visible
Infrared
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Infrared
Spectrometry
 Material absorbs energy in the near-IR region of the electromagnetic
spectrum.
 Compares the IR light beam before and after passing through a
transparent sample.
 Result—an absorption or transmittance spectrum
 Gives a unique view of the substance; like a fingerprint
 See how a spectrophotometer works www.prenhall.com/hsforensics
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Mass Spectrometry
Gas chromatography has one major drawback: It does not give a
specific identification. Mass spectrometry cannot separate mixtures. By
combining the two (GC-MS), constituents of mixtures can be
specifically identified.
Watch the GC/MS at work www.prenhall.com/hsforensics
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Mass Spectrometry, continued
In a mass spectrometer, an electron beam is directed at sample
molecules in a vacuum chamber. The electrons break apart the sample
molecules into many positive-charged fragments. These are sorted and
collected according to their mass-to-charge ratio by an oscillating
electric or magnetic field.
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Mass Spectra
Each molecular species has its own unique mass spectrum.
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IR Spectrophotometry and Mass Spectrometry
Both work well in identifying pure substances.
Mixtures are difficult to identify in both techniques.
Both are compared to a catalog of knowns.
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People of Historical Significance
Arthur Jeffrey Dempster was born in Canada, but studied at and
received his PhD from the University of Chicago. He began teaching
physics there in 1916. In 1918, Dempster developed the first modern
mass spectrometer. His version was over 100 times more accurate than
previous ones and established the basic theory and design of mass
spectrometers that is still used to this day.
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People of Historical Significance, continued
Francis William Aston was a British physicist who won the 1922
Nobel Prize in Chemistry for his work in the invention of the mass
spectrograph. He used a method of electromagnetic focusing to
separate substances. This enabled him to identify no fewer than 212
of the 287 naturally occurring elemental isotopes.
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Forensic toxicology helps determine (a)
the cause-and-effect 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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Poison—Murder, Accidental Overdoses, and Drug Offenses
®
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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Drugs
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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Drugs
Controlled Substances
Narcotics
Narcotics reduce pain and can be very habit forming.
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Drugs
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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Drugs
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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Drugs
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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Drugs
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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Drugs
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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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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Drugs
Controlled Substances
Pesticides and Heavy Metals
Metal compounds can damage many organs in the body.
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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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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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. . . . . . . . . . . . . . . . . Summary
® Forensic toxicology seeks to identify poisons or drugs
®
®
®
®
®
in criminals and victims.
Toxicology is important in studying cases of drug
overdose and sporting violations.
Controlled substances fall into five main groups.
Poisons can be produced by living organisms.
Pesticides and heavy metals are common poisons.
Bioterrorism agents include ricin and anthrax.
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