Chapter 7 Drugs

1. Chapter 7Drugs “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

2. 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. Kendall/Hunt Publishing Company

3. 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 Kendall/Hunt Publishing Company

4. 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 Kendall/Hunt Publishing Company

5. Blood Urine Hair Gastric Contents Bile Liver tissue Brain tissue Kidney tissue Spleen tissue Vitreous Humor of the Eye Human ComponentsUsed for Drug Analysis Kendall/Hunt Publishing Company

6. Identification of Drugs • PDR—Physicians’ Desk Reference • Field Tests—presumptive tests • Laboratory Tests—conclusive tests Kendall/Hunt Publishing Company

7. 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. Kendall/Hunt Publishing Company

8. Screening or presumptive tests Spot or color tests Microcrystalline test— a reagent is added that produces a crystalline precipitate which is unique for a certain drug. Chromatography Confirmatory tests Spectrophotometry Ultraviolet (UV) Visible Infrared (IR) Mass spectrometry Drug Identification Kendall/Hunt Publishing Company

9. 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 Presumptive Color Tests Kendall/Hunt Publishing Company

10. 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. Kendall/Hunt Publishing Company

11. Paper Chromatography • Stationary phase—paper • Mobile phase—a liquid solvent Capillary action moves the mobile phase through the stationary phase Kendall/Hunt Publishing Company

12. Spectroscopy • Spectroscopy—the interaction of electromagnetic radiation with matter. • Spectrophotometer—an instrument used to measure and record the absorption spectrum of a chemical substance. Kendall/Hunt Publishing Company

13. 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 Kendall/Hunt Publishing Company

14. 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 Kendall/Hunt Publishing Company

15. 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. Kendall/Hunt Publishing Company

16. 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. Kendall/Hunt Publishing Company

17. Mass Spectra Each molecular species has its own unique mass spectrum. Kendall/Hunt Publishing Company

18. IR Spectrophotometry andMass Spectrometry • Both work well in identifying pure substances. • Mixtures are difficult to identify in both techniques • Both are compared to a catalog of knowns Kendall/Hunt Publishing Company

19. Chapter 8Toxicology:Poisons and Alcohol “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 —Jhn Trestrail from “Criminal Poisoning”

20. 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 Kendall/Hunt Publishing Company

21. Forensic Toxicology • Postmortem—medical examiner or coroner • Criminal—motor vehicle accidents (MVA) • Workplace—drug testing • Sports—human and animal • Environment—industrial, catastrophic, terrorism Kendall/Hunt Publishing Company

22. Toxicology Toxic substances may: • Be a cause of death • Contribute to death • Cause impairment • Explain behavior Kendall/Hunt Publishing Company

23. 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” Kendall/Hunt Publishing Company

24. 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 Kendall/Hunt Publishing Company

25. 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 Kendall/Hunt Publishing Company

26. Toxicity Classes Kendall/Hunt Publishing Company

27. 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) Kendall/Hunt Publishing Company

28. Symptoms of Various Typesof Poisoning Type of PoisonSymptom/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 Kendall/Hunt Publishing Company

29. 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 Critical Informationon Poisons Kendall/Hunt Publishing Company

30. 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 Kendall/Hunt Publishing Company

31. 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 Kendall/Hunt Publishing Company

32. Blood Urine Vitreous Humor of Eyes Bile Gastric contents Liver tissue Brain tissue Kidney tissue Hair/nails Human Specimens for Analysis Kendall/Hunt Publishing Company

33. 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 Kendall/Hunt Publishing Company

34. 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 Kendall/Hunt Publishing Company

35. BACBlood 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 Kendall/Hunt Publishing Company

36. 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 Kendall/Hunt Publishing Company

37. Henry’s Law • The concentration of alcohol in breath is proportional to that in the blood. • This ratio of alcohol in the blood to the alcohol in the lungs 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. Kendall/Hunt Publishing Company

38. 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. Kendall/Hunt Publishing Company

39. 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 + 3C2H5OH+ 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 Kendall/Hunt Publishing Company

40. 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. Kendall/Hunt Publishing Company