drugs_ alcohol_ and toxicology notes by wuyunyi

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									                    Unit #7
  Drugs, Alcohol,
  and Toxicology
“Having sniffed the dead man’s lips, I
 detected a slightly sour smell, and I
 came to the conclusion that he had
      poison forced upon him.”

   —Sherlock Holmes, in Sir Arthur Conan Doyle’s
                                        A Study in Scarlet

       Unit # 7 - Drugs, Alcohol, and                    1
                 Toxicology
                          Drugs
    Students will learn:
   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, over-the-counter
    medications, and illegal drugs.




                       Unit # 7 - Drugs, Alcohol, and   2
                                 Toxicology
                       Drugs
    Students 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.


                    Unit # 7 - Drugs, Alcohol, and   3
                              Toxicology
   Drugs

                           Describe IR, UV-VIS
                            spectroscopy, and GC-MS
                           Present and interpret data
                            with graphs.
                           Use the Physicians’ Desk
                            Reference (PDR) to
                            identify pills.
                           Use technology and
                            mathematics to improve
                            investigations and
                            communications.



Unit # 7 - Drugs, Alcohol, and                     4
          Toxicology
     Drugs and Crime

 A drug is a natural or synthetic substance
  designed to affect the subject psychologically or
  physiologically.
 “Controlled substances” are drugs that are
  restricted by law
 Controlled Substances Act is a law that was
  enacted in 1970; it lists illegal drugs, their category
  and their penalty for possession, sale or use.



                Unit # 7 - Drugs, Alcohol, and          5
                          Toxicology
Controlled Substances Act
    Schedule I—high potential for abuse; no currently acceptable
     medical use in the US; a lack of accepted safety for use under
     medical supervision
    Schedule II—high potential for abuse; a currently accepted
     medical use with severe restrictions; abuse may lead to severe
     psychological or physical dependence
    Schedule III—lower potential for abuse than the drugs in I or II; a
     currently accepted medical use in the US; abuse may lead to
     moderate physical dependence or high psychological dependence
    Schedule IV—low potential for abuse relative to drugs in III; a
     currently accepted medical use in the US; abuse may lead to
     limited physical or psychological dependence relative to drugs in III
    Schedule V—low potential for abuse relative to drugs in IV;
     currently accepted medical use in the US; abuse may lead to
     limited physical or psychological dependence relative to drugs in IV

                 Unit # 7 - Drugs, Alcohol, and                        6
                           Toxicology
           Examples of Controlled
        Substances and Their Schedule
                 Placement
 Schedule I—heroin (diacetylmorphine), LSD, marijuana,
  ecstasy (MDMA)
 Schedule II—cocaine, morphine, amphetamines (including
  methamphetamines), PCP, Ritalin
 Schedule III—intermediate acting barbiturates, anabolic
  steroids, ketamine
 Schedule IV—other stimulants and depressants including
  Valium, Xanan, Librium, phenobarbital, Darvon
 Schedule V—codeine found in low doses in cough medicines




                    Unit # 7 - Drugs, Alcohol, and       7
                              Toxicology
Identification of Drugs


   PDR—Physicians’ Desk Reference
   Field Tests—presumptive tests
   Laboratory Tests—conclusive
    tests



         Unit # 7 - Drugs, Alcohol, and   8
                   Toxicology
          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



                 Unit # 7 - Drugs, Alcohol, and         9
                           Toxicology
  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, whether it
is a prescription, over the counter, or a
controlled substance; as well as more
detailed information about the drug.
        Unit # 7 - Drugs, Alcohol, and     10
                  Toxicology
Drug Identification
                             Confirmatory tests
Screening or              Spectrophotometry
presumptive tests            Ultraviolet (UV)
  Spot or color tests       Visible
  Microcrystalline test—  Infrared (IR)
   a reagent is added  Mass spectrometry
   that produces a
   crystalline precipitate
   which is unique for a
   certain drug.
  Chromatography



            Unit # 7 - Drugs, Alcohol, and        11
                      Toxicology
Presumptive Color Tests

   Marquis—turns purple in the
    presence of most opium
    derivatives and orange-brown
    with amphetamines
   Dillie-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

             Unit # 7 - Drugs, Alcohol, and   12
                       Toxicology
        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.


                Unit # 7 - Drugs, Alcohol, and   13
                          Toxicology
       Types of Chromatography
   Paper
   Thin Layer (TLC)
   Gas (GC)
   Pyrolysis Gas (PGC)
   Liquid (LC)
   High Pressure Liquid (HPLC)
   Column

                 Unit # 7 - Drugs, Alcohol, and   14
                           Toxicology
   Paper Chromatography

 Stationary phase—paper
 Mobile phase—a liquid
  solvent



         Capillary action moves
         the mobile phase
         through the stationary
         phase

                 Unit # 7 - Drugs, Alcohol, and   15
                           Toxicology
  Thin Layer
Chromatography
                         Stationary phase—
                          a thin layer of coating
                          (usually alumina or
                          silica) on a sheet of
                          plastic or glass
                         Mobile phase—
                          a liquid solvent


 Unit # 7 - Drugs, Alcohol, and              16
           Toxicology
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).


                 Unit # 7 - Drugs, Alcohol, and   17
                           Toxicology
      Gas Chromatography
Phases                                      Analysis
 Stationary—a solid or a                    Shows a peak that is
  viscous liquid that lines a tube            proportional to the
  or column                                   quantity of the substance
 Mobile—an inert gas like                    present
  nitrogen or helium                         Uses retention time
                                              instead of Rf for the
                                              qualitative analysis




                        Unit # 7 - Drugs, Alcohol, and                18
                                  Toxicology
         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).

           Unit # 7 - Drugs, Alcohol, and           19
                     Toxicology
            Spectroscopy
 Spectroscopy—the interaction of electromagnetic
  radiation with matter.
 Spectrophotometer—an instrument used to measure
  and record the absorption spectrum of a chemical
  substance.




                  Unit # 7 - Drugs, Alcohol, and     20
                            Toxicology
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
           Unit # 7 - Drugs, Alcohol, and      21
                     Toxicology
      Infrared Spectometry




 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


                         Unit # 7 - Drugs, Alcohol, and             22
                                   Toxicology
     Mass Spectrometry
Gas chromatography has one major drawback, it does
not give a specific identification. Mass spectrometry
cannot separate mixtures. By combining the two
(GCMS), constituents of mixtures can be specifically
identified.




                  Unit # 7 - Drugs, Alcohol, and        23
                            Toxicology
Mass Spectrometry

 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 a magnetic field.


        Unit # 7 - Drugs, Alcohol, and   24
                  Toxicology
Mass Spectra




Each molecular species has its own
unique mass spectrum.
      Unit # 7 - Drugs, Alcohol, and   25
                Toxicology
      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




               Unit # 7 - Drugs, Alcohol, and   26
                         Toxicology
               People of Historical
                        Significance received
Arthur Jeffrey Dempster was born in Canada, but studied and
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 developed, and established the basic theory and design
of mass spectrometers that is still used to this day.




                        Unit # 7 - Drugs, Alcohol, and                 27
                                  Toxicology
         People of Historical
            Significance
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.




                  Unit # 7 - Drugs, Alcohol, and        28
                            Toxicology
            Unit #7
Drugs, Alcohol, and
    Toxicology
  “All substances are poisons.
  There is none which is not.
  The right dose differentiates a
  poison and remedy.”
     —Paracelsus (1495-1541). Swiss
         physician and chemist


         Unit # 7 - Drugs, Alcohol, and   29
                   Toxicology
Toxicology and Alcohol


                        Students will learn:

                         • A quantitative approach to
                           toxicology.
                         • The danger of using alcohol.




       Unit # 7 - Drugs, Alcohol, and                   30
                 Toxicology
Toxicology and Alcohol
    Students will be able to:
                     Discuss the connection of blood alcohol
                      levels to the law, incapacity, and test
                      results.
                     Understand the vocabulary of poisons.
                     Design and conduct scientific
                      investigations.
                     Use technology and mathematics to
                      improve investigations and
                      communications.
                     Identify questions and concepts that guide
                      scientific investigations.
                     Communicate and defend a scientific
                      argument.
          Unit # 7 - Drugs, Alcohol, and                     31
                    Toxicology
            Toxicology
Definition—the study of the adverse effects
 of chemicals or physical agents on living
 organisms.
Types:
  – Environmental—air, water, soil
  – Consumer—foods, cosmetics, drugs
  – Medical, clinical, forensic

               Unit # 7 - Drugs, Alcohol, and   32
                         Toxicology
    Forensic Toxicology
• Postmortem—medical examiner or
  coroner
• Criminal—motor vehicle accidents (MVA)
• Workplace—drug testing
• Sports—human and animal
• Environment—industrial, catastrophic,
  terrorism

              Unit # 7 - Drugs, Alcohol, and   33
                        Toxicology
           Toxicology
Toxic substances may:
  – Be a cause of death
  – Contribute to death
  – Cause impairment
  – Explain behavior




              Unit # 7 - Drugs, Alcohol, and   34
                        Toxicology
    Historical Perspective
         of Poisoners
• Olympias—a famous Greek poisoner
• Locusta—personal poisoner of Emperor Nero
• Lucretia Borgia—father was Pope Alexander VI
• Madame Giulia Toffana—committed over 600
  successful poisonings, including two Popes.
• Hieronyma Spara—formed a society to teach women
  how to murder their husbands
• Madame de Brinvilliers and Catherine Deshayes—
  French poisoners.
  AND many others through modern times.



                  Unit # 7 - Drugs, Alcohol, and    35
                            Toxicology
The Severity of the Problem
  “If all those buried in our cemeteries
  who were poisoned could raise their
  hands, we would probably be shocked
  by the numbers.”
              —John Harris Trestrail, “Criminal Poisoning”




              Unit # 7 - Drugs, Alcohol, and             36
                        Toxicology
    People of Historical
       Significance
Mathieu Orfila—known as
the father of forensic
toxicology, published in
1814 “Traite des Poisons”
which described the first
systematic approach to the
study of the chemistry and
physiological nature of
poisons.




                  Unit # 7 - Drugs, Alcohol, and   37
                            Toxicology
       Aspects of Toxicity

• Dosage
• The chemical or physical form of the substance
• The mode of entry into the body
• Body weight and physiological conditions of the
  victim, including age and sex
• The time period of exposure
• The presence of other chemicals in the body or
  in the dose
                  Unit # 7 - Drugs, Alcohol, and    38
                            Toxicology
             Lethal Dose
• LD50—refers to the dose of a substance
  that kills half the test population, usually
  within four hours
• Expressed in milligrams of substance per
  kilogram of body weight




                 Unit # 7 - Drugs, Alcohol, and   39
                           Toxicology
               Toxicity Classes

LD50 (rat,oral)   Correlation to                    Toxicity
                  Ingestion by 150 lb
                  Adult Human
<1mg/kg           a taste to a drop                 extremely

1-50 mg/kg        to a teaspoon                     highly

50-500 mg/kg      to an ounce                       moderately

500-5000 mg/kg    to a pint                         slightly

5-15 g/kg         to a quart                        practically non-toxic

Over 15g/kg       more than 1 quart                 relatively harmless
                   Unit # 7 - Drugs, Alcohol, and                           40
                             Toxicology
        Federal Regulatory
            Agencies
•   Food and Drug Administration (FDA)
•   Environmental Protection Agency (EPA)
•   Consumer Product Safety Commission
•   Department of Transportation (DOT)
•   Occupational Safety and Health
    Administration (OSHA)


                 Unit # 7 - Drugs, Alcohol, and   41
                           Toxicology
Symptoms of Various Types
      of Poisoning
Type of Poison                      Symptom/Evidence
•   Caustic Poison (lye)            Characteristic burns around the lips and
                                    mouth of the victim
•   Carbon Monoxide                 Red or pink patches on the chest and thighs,
                                    unusually bright red lividity
•   Sulfuric acid                   Black vomit
•   Hydrochloric acid               Greenish-brown vomit
•   Nitric acid                     Yellow vomit
•   Phosphorous                     Coffee brown vomit. Onion or garlic odor
•   Cyanide                         Burnt almond odor
•   Arsenic, Mercury                Pronounced diarrhea
•   Methyl (wood) or                Nausea and vomiting, unconsciousness,
    Isopropyl (rubbing) alcohol     possibly blindness

                           Unit # 7 - Drugs, Alcohol, and                    42
                                     Toxicology
              Critical Information
                   on Poisons
•   Form                                     •Symptoms resulting from an acute
•   Common color                              exposure
•   Characteristic odor                    • Symptoms resulting from chronic
•   Solubility                                exposure
•   Taste                                  • Disease states mimicked by
•   Common sources                            poisoning
•   Lethal dose                            • Notes relating to the victim
•   Mechanism                              • Specimens from victim
•   Possible methods of administration     • Analytical detection methods
•   Time interval of onset of              • Known toxic levels
    symptoms.                              • Notes pertinent to analysis of
                                              poison
                                           • List of cases in which poison was
                                              used
                                         —John Trestrail from “Criminal Poisoning”
                             Unit # 7 - Drugs, Alcohol, and                     43
                                       Toxicology
         To Prove a Case
•   Prove a crime was committed
•   Motive
•   Intent
•   Access to poison
•   Access to victim
•   Death was caused by poison
•   Death was homicidal


                 Unit # 7 - Drugs, Alcohol, and   44
                           Toxicology
       Forensic Autopsy

Look for:
  – Irritated tissues
  – Characteristic odors
  – Mees lines—single transverse white bands on nails.
Order toxicological screens
  – Postmortem concentrations should be done at the
    scene for comparison
  – No realistic calculation of dose can be made from a
    single measurement
                  Unit # 7 - Drugs, Alcohol, and      45
                            Toxicology
 Human Specimens for
      Analysis
• Blood                                •   Liver tissue
• Urine                                •   Brain tissue
• Vitreous Humor of                    •   Kidney tissue
  Eyes                                 •   Hair/nails
• Bile
• Gastric contents



              Unit # 7 - Drugs, Alcohol, and               46
                        Toxicology
     Alcohol—Ethyl Alcohol
                     (C2H5OH)
• Most abused drug in America
• About 40% of all traffic deaths are alcohol-related
• Toxic—affecting the central nervous system, especially
    the brain
•   Colorless liquid, generally diluted in water
•   Acts as a depressant
•   Alcohol appears in blood within minutes of consumption;
    30-90 minutes for full absorption
•   Detoxification—about 90% in the liver
•   About 5% is excreted unchanged in breath, perspiration
    and urine

                      Unit # 7 - Drugs, Alcohol, and          47
                                Toxicology
     Rate of Absorption
Depends on:
  – amount of alcohol consumed
  – the alcohol content of the beverage
  – time taken to consume it
  – quantity and type of food present in the
    stomach
  – physiology of the consumer


                Unit # 7 - Drugs, Alcohol, and   48
                          Toxicology
          BAC
 Blood Alcohol Content
• Expressed as percent weight per volume of
  blood
• Legal limits in all states is 0.08%
• Parameters influencing BAC:
     Body weight
     Alcoholic content
     Number of beverages consumed
     Time between consumption



                 Unit # 7 - Drugs, Alcohol, and   49
                           Toxicology
                   BAC
• Burn off rate of 0.015% per hour but can
  vary:
 Male
  BAC male = 0.071 x (oz) x (% alcohol)
                 body weight
 Female
  BAC female = 0.085 x (oz) x (% alcohol)
                  body weight



             Unit # 7 - Drugs, Alcohol, and   50
                       Toxicology
                 Henry’s Law

• When a volatile chemical is dissolved in a liquid and is
  brought to equilibrium with air, there is a fixed ratio
  between the concentration of the volatile compound in
  the air and its concentration in the liquid; this ratio is
  constant for a given temperature. THEREFORE, the
  concentration of alcohol in breath is proportional to that in
  the blood.
• This ratio of alcohol in the blood to alcohol in the alveolar
  air is approximately 2100 to 1. In other words 1 ml of
  blood will contain nearly the same amount of alcohol as
  2100 ml of breath.
                      Unit # 7 - Drugs, Alcohol, and         51
                                Toxicology
                  Field Tests
• Preliminary tests—used to determine the degree of
  suspect’s physical impairment and whether or not
  another test is justified.
• Psychophysical tests—3 Basic Tests
    Horizontal gaze nystagmus (HGN): follow a pen or small
     flashlight, tracking left to right with one’s eyes. In general,
     wavering at 45 degrees indicates 0.10 BAC.
    Nine Step walk and turn (WAT): comprehend and execute
     two or more simple instructions at one time.
    One-leg stand (OLS): maintain balance, comprehend and
     execute two or more simple instructions at one time.


                       Unit # 7 - Drugs, Alcohol, and                  52
                                 Toxicology
            The Breathalyzer
• More practical in the field
• Collects and measures alcohol content of alveolar breath
• Breath sample mixes with 3 ml of 0.025 % K2Cr2O7 in sulfuric
  acid and water
  2K2Cr2O7 + 3C 2H5OH + 8H 2SO4  2Cr2(SO4)3 + 2K2SO4 + 3CH3COOH + 11 H2O
• Potassium dichromate is yellow, as concentration decreases its
  light absorption diminishes so the breathalyzer indirectly
  measures alcohol concentration by measuring light absorption of
  potassium dichromate before and after the reaction with alcohol




                         Unit # 7 - Drugs, Alcohol, and                53
                                   Toxicology
            Generalizations
• During absorption, the concentration of alcohol in arterial
  blood will be higher than in venous blood.
• Breath tests reflect alcohol concentration in the pulmonary
  artery.
• The breathalyzer also can react with acetone (as found
  with diabetics), acetaldehyde, methanol, isopropyl alcohol,
  and paraldehyde, but these are toxic and their presence
  means the person is in serious medical condition.
• Breathalyzers now use an infrared light absorption device
  with a digital read-out. Prints out a card for a permanent
  record.
                     Unit # 7 - Drugs, Alcohol, and       54
                               Toxicology
        People in the News

John Trestrail is a practicing toxicologist
who has consulted on many criminal
poisoning cases. He is the founder of the
Center for the Study of Criminal Poisoning
in Grand Rapids, Michigan which has
established an international database to
receive and analyze reports of homicidal
poisonings from around the world. He is
also the director of DeVos Children’s
Hospital Regional Poison Center. In
addition, he wrote the book, Criminal
Poisoning, used as a reference by law
enforcement, forensic scientists and
lawyers.


                          Unit # 7 - Drugs, Alcohol, and   55
                                    Toxicology

								
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