Science Fair Project

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Toxicology Poisons and Alcohol
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Objectives

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

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Objectives, continued

• You 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.

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Toxicology

• Toxicologythe study of the adverse effects of
  chemicals or physical agents on living organisms
• Types
• Environmentalair, water, soil
• Consumerfoods, cosmetics, drugs
• Medical, clinical, forensic

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Forensic Toxicology

• Postmortemmedical examiner
• or coroner
• Criminalmotor vehicle
• accidents (MVA)
• Workplacedrug testing
• Sportshuman and animal
• Environmentindustrial,
• catastrophic, terrorism

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Toxicology

• Toxic substances may
• Be a cause of death
• Contribute to death
• Cause impairment
• Explain behavior

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Historical Perspective of Poisoners

• Olympiasa famous Greek poisoner
• Locustapersonal poisoner of Emperor Nero
• Lucretia Borgiafather was Pope Alexander VI
• Madame Giulia Toffanacommitted over 600
  successful poisonings, including two popes
• Hieronyma Sparaformed a society to teach women
  how to murder their husbands
• Madame de Brinvilliers and Catherine
  DeshayesFrench poisoners
• AND many others through modern times.

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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

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People of Historical Significance

• Mathieu Orfilaknown as the father of forensic
  toxicology, published in 1814 Traité des poisons
  which described the first systematic approach to
  the study of the chemistry and physiological
  nature of poisons

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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

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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

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Toxicity Classification
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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)

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Symptoms of Various Types of Poisoning

• Symptom/Evidence
• Characteristic burns around the lips and
• mouth of victim
• Red or pink patches on the chest and
• thigh, unusually bright red lividity
• Black vomit
• Greenish-brown vomit
• Yellow vomit
• Coffee-brown vomit, onion or garlic odor
• Burnt almond odor
• Extreme diarrhea
• Nausea and vomiting, unconsciousness
• possibly blindness

Type of Poison Caustic poison (lye) Carbon
monoxide Sulfuric acid Hydrochloric acid Nitric
acid Phosphorus Cyanide Arsenic, mercury Methyl
(wood) or isopropyl (rubbing) alcohol
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Critical Information

• Form
• Common color
• Characteristic odor
• Solubility
• Taste
• Common sources
• Lethal dose
• Mechanism
• Possible methods of administration
• Time interval of onset of symptoms

• Symptoms resulting from an acute exposure
• Symptoms resulting from chronic exposure
• Disease states mimicked by poisoning
• Notes relating to the victim
• Specimens from victim
• Analytical detection methods
• Known toxic levels
• Notes pertinent to analysis of poison
• List of cases in which poison was used

John Trestrail from Criminal Poisoning
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To Prove a Case

• Prove a crime was committed
• Motive
• Intent
• Access to poison
• Access to victim
• Death was homicidal
• Death was caused by poison

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Forensic Autopsy

• Look for
• Irritated tissues
• Characteristic odors
• Mees linessingle 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.

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Human Specimens for Analysis

• Blood
• Urine
• Vitreous humor of eyes
• Bile
• Gastric contents

• Liver tissue
• Brain tissue
• Kidney tissue
• Hair/nails

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AlcoholEthyl Alcohol (C2H5OH)

• Most abused drug in America
• About 40 percent of all traffic deaths are
  alcohol-related
• Toxicaffecting 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 3090 minutes for full absorption
• Detoxificationabout 90 percent in the liver
• About 5 percent is excreted unchanged in breath,
  perspiration, and urine

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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

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BAC Blood Alcohol Content

• Expressed as percent weight per volume of blood
• Legal limit in all states is 0.08 percent

• Parameters influencing BAC
• Body weight
• Alcohol content
• Number of beverages consumed
• Time since consumption

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BAC Calculation

• Burn-off rate of 0.015 percent per hour, but can
  vary

• Male
• BAC
• Female
• BAC

0.071 ? (oz) ? ( alcohol) body weight
0.085 ? (oz) ? ( alcohol) body weight
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Henrys 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 2,100 to 1. In
  other words, 1 ml of blood will contain nearly
  the same amount of alcohol as 2,100 ml of breath.

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Field Tests

• Preliminary testsused to determine the degree of
  suspects physical impairment and whether or not
  another test is justified
• Psychophysical teststhree basic tests
• Horizontal gaze nystagmus (HGN) follow a pen or
  small flashlight, tracking left to right with
  ones 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

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The Breathalyzer

• More practical in the field
• Collects and measures alcohol content
• of alveolar breath
• Breath sample mixes with 3 ml of 0.025 percent
  K2Cr2O7 in sulfuric acid and water
• 2K2Cr2O7 3C2H5OH 8H2SO4 ? 2Cr2(SO4)3
  2K2SO4 3CH3COOH 11H2O
• 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.

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Generalizations

• During absorption, the concentration of alcohol
  in arterial blood is higher than in venous blood.
• Breath tests reflect alcohol concentration in the
  pulmonary artery.
• The breathalyzer also can react with acetone (as
  found in 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 readout.
  Prints out a card for a permanent record.

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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 Childrens Hospital Regional
  Poison Center. In addition, he wrote the book
  Criminal Poisoning, used as a reference by law
  enforcement personnel, forensic scientists, and
  lawyers.

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More Information

• Read more about forensic toxicology at truTVs
  Crime Library
• http//www.crimelibrary.com/criminal_mind/forensi
  cs/toxicology/2.html