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FORENSIC SCIENCE Toxicology

FORENSIC SCIENCE Toxicology. Toxicology. Study of poisons or the detection of foreign substances in the body that can have a toxic effect such as: Alcohol Industrial chemicals Poisonous gas Illegal drugs Drug overdoses. TOXICOLOGY. TYPES: Environmental--air, water, soil

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FORENSIC SCIENCE Toxicology

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  1. FORENSIC SCIENCEToxicology

  2. Toxicology • Study of poisons or the detection of foreign substances in the body that can have a toxic effect such as: • Alcohol • Industrial chemicals • Poisonous gas • Illegal drugs • Drug overdoses

  3. TOXICOLOGY TYPES: • Environmental--air, water, soil • Consumer--foods, cosmetics, drugs • Medical, clinical, forensic

  4. Forensic Toxicology • Postmortem--medical examiner or coroner • Criminal--motor vehicle accidents (MVA), assault, etc. • Workplace drug testing • Sports--human and animal

  5. Why do Toxicology? Toxicology can: • Be a cause of death • Contribute to death • Cause impairment • Explain behavior

  6. OUR STUDY • Drugs • Poisons • Alcohol Basically, toxicology involves the: separation,detection,identificationand measurementof the drug and/or poison.

  7. Drugs and Crime • Drug-a natural or synthetic substance designed to affect the subject psychologically or physiologically. • “Controlled substances”--drugs that are restricted by law • Controlled Substances Act--enacted in 1970 lists illegal drugs, their category and their penalty for possession, sale or use.

  8. Controlled Substances Act • Schedule 1 • no currently accepted medical use • lack of accepted safety for use under medical supervision • high potential for abuse. • Examples: • Heroin, LSD, Marijuana, Peyote, Meth

  9. Controlled Substances Act • Schedule 2 • High potential for abuse  • Accepted for medical use • Examples: • Narcotics: Demerol, oxycodone, morphine • Stimulants: Adderall, Ritalin

  10. Controlled Substances Act • Schedule 3 • Accepted for Medical Use • Lower risk of addiction • Examples: • Combinations of schedule 2 with other drugs

  11. Controlled Substances Act • Schedule 4 • Accepted for Medical Use • Low risk of addiction • Examples: • Xanax, Valium,

  12. Controlled Substances Act • Schedule 5 • Accepted for Medical Use • Very little risk of addiction • Examples: • Preparations containing limited amounts of higher scheduled drugs; robitussen

  13. Types of Testing • PDR’s--Physician’s Desk Reference • Information on drug and symptoms • Field Tests--presumptive tests • Lab Tests--conclusive tests

  14. PDR’s

  15. Screening tests or presumptive tests Color tests Microcrystalline test--a reagent is added that produces a crystalline precipitate which are unique for certain drugs. DRUG IDENTIFICATION

  16. Presumptive Color Tests • Marquis—purple = opiums; orange/brown= amphetamines • Dillie-Koppanyi--turns violet-blue in the presence of barbiturates

  17. Presumptive Color Tests • Duquenois-Levine--turns a purple color in the presence of marijuana

  18. Add HCL (hydrochloric acid) Add Duqeunois reagent Add Chloroform

  19. Presumptive Tests • Van Urk--turns a blue-purple in the presence of LSD • Scott test--color test for cocaine – turns blue

  20. Confirmation tests Chromatography Spectrophotometry Mass spectrometry DRUG IDENTIFICATION

  21. Confirmation TestsChromatography • Chromatography • Techniques for separating mixtures into their component compounds • Moblie Phase – something that moves • Stable phase – something that stays stable • Mobile phase moves through stable phase

  22. Types of Chromatography • Paper • Thin Layer • Gas • Pyrolysis Gas • High Pressure Liquid (HPLC)

  23. Paper Chromatography • Stationary phase--paper • Mobile phase--a liquid solvent Capillary action moves the mobile phase through the stationary phase

  24. Thin Layer Chromatography • Stationary phase--a thin layer of coating on a sheet of plastic or glass (usually aluminum or silica) • Mobile phase--a liquid solvent from www.lbp.police.uk

  25. Retention Factor (Rf) • Rf=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.

  26. Results from Thin Layer • What was in the unknown sample? • Cocaine • Heroin • Methamphtamine

  27. Gas Chromatography • Stationary phase--a solid or very syrupy liquid lines a tube or column • Mobile phase--an inert gas like nitrogen or helium

  28. Pyrolysis Gas Chromatography • Used when a sample does not readily dissolve in a solvent • If heating this sample decomposes it into gaseous products, these products can be analyzed by CGC

  29. A pyrogram is a visual representation of the results

  30. High Pressure LiquidChromatography • Stationary phase--fine solid particles • Mobile phase--a liquid solvent

  31. Liquid Chromatography

  32. Mass Spectrometry Gas chromatography has one major drawback--it does not give a specific identification. By teaming a gas chromatograph with a mass spectrometer, identification is accomplished.

  33. MS (cont.) Mass spectrometer creates a fragmentation pattern. NO TWO SUBSTANCES PRODUCE THE SAME FRAGMENTATION PATTERN.

  34. Example of a GS/MS

  35. Blood Urine Vitreous Bile Liver tissue Brain tissue Kidney tissue Spleen tissue Human Analysisfor Drugs

  36. “If all those buried in our cemeteries who were poisoned could raise their hands, we would probably be shocked by the numbers. --John Trestrail

  37. POISONERS in HISTORY • 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.

  38. Symptoms of VariousTypes 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 brighter 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, Isopropyl (rubbing) alcohol unconsciousness, possibly blindness

  39. 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 Points to Know about aPoison from “Criminal Poisoning” by John Trestrail

  40. New Terror--Yuschenko In 2004, Viktor Yushchenko announced independent candidate for president of the Ukraine. His major rival was Prime Minister Viktor Yanukovych. The campaign was often bitter, controversial, and violent, with accusations of "dirty tricks" from both sides. Yushchenko became seriously ill in early September 2004. On December 11, Austrian doctors confirmed Yushchenko was poisoned with TCDD dioxin having had more than 1,000 times the usual concentration in his body. This is the second highest dioxin level ever measured in a human. No one has ever been tried for this crime.

  41. Evidence • Class Presumptive or screening tests can be used to determine that it is a drug. • Individual Chromatography, especially in conjunction with mass spectrometry, will specifically identify a drug or poison and its components.

  42. Toxicology of Alcohol

  43. Statistics • Nearly 17,500 automobile deaths in the U.S. • 40% of all auto fatalities are due to alcohol • Over 2 million people/year injured, requiring hospitalization due to alcohol • Most abused drug; Must be able to test rapidly/accurately, due to legal needs

  44. Alcohol--Ethyl Alcohol: C2H5OH • Toxic--affecting the central nervous system, especially the brain • Toxicologists can test for alcohol in body fluids, tissues, organs • 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

  45. Effects of Increasing BloodAlcohol .02 MELLOW FEELING. SLIGHT BODY WARMTH. LESS INHIBITED. .05 NOTICEABLE RELAXATION. LESS ALERT. LESS SELF-FOCUSED. COORDINATION IMPAIRMENT BEGINS. .08 DRUNK DRIVING LIMIT. DEFINITE IMPAIRMENT IN COORDINATION AND JUDGMENT. .10 NOISY. POSSIBLE EMBARRASSING BEHAVIOR. MOOD SWINGS. REDUCTION IN REACTION TIME. .15 IMPAIRED BALANCE AND MOVEMENT. CLEARLY DRUNK. .30 MANY LOSE CONSCIOUSNESS .40 MOST LOSE CONSCIOUSNESS; SOME DIE. .50 BREATHING STOPS. MANY DIE.

  46. 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

  47. BACBlood Alcohol Content • Expressed as percent weight per volume • Legal limits in most states is 0.08% • Parameters influencing BAC: • Body weight • Alcoholic content • Number of beverages consumed • Time between consumption

  48. BAC • Burn off rate if 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

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