Forensic Toxicology

1. Forensic Toxicology

2. Toxicology (from the Greek wordtoxicosmeaning "poisonous" -logos (-ology) = the study of Toxicology is the study of the adverse effects of chemicals on living organisms. It is the study of symptoms, mechanisms, treatments and detection of poisoning, especially the poisoning of people.

3. Forensic Toxicology • Forensic toxicology-includes measurement of alcohol, drugs and other toxic substances in biological specimens and interpretation of results in a medicolegal context. • Drug article…goto DEA • http://www.justice.gov/dea/pubs/states/newsrel/2010/mia012910.html

4. Who is the Father of Toxicology?

5. Mathieu OrfilaMathieu Joseph Bonaventure Orfila The modern father of toxicology, having given the subject its first formal treatment in 1813 in his Traité des poisons, also called Toxicologie générale

6. 16th century physician Paracelsus “All substances are poisons; there is none which is not a poison. The right dose differentiates a poison from a remedy.”

7. Forensic Toxicology • Accidental Poisoning • Drug Abuse/Overdose • Suicidal/Homicidal Poisoning • Rate of Reaction in body • Recovery rates

8. Metabolism • Metabolism-transformation of one chemical into another by the body-producing metabolites • An individual’s metabolism is unique from any other person. • How fast/slow you metabolize food, drugs, alcohol or anything else put in your system is unique to you. • People with particular diseases (like Diabetes, respiratory disease, thyroid, cancer many others) metabolize substances differently.

9. Respiratory Disease

10. Alzheimer’s Disease

11. Who needs a toxicology report? • If the techies on CSI: Miami can whip up toxicological statements in no time, why does it take so darn long in the real world? • BACKLOG (to many cases going to one lab at a time NOTE: not all agencies have a toxicology unit) • STAFF SHORTAGE • If you need expert testimony in a trial, an expert has to handle/TEST the substances

12. HOW MANY LABS ARE THERE? • It depends on the state!! • FLORIDA= 2 • FLORIDA1. Fort Myers 2. Miami Toxicology Testing Service, Inc.Diagnostic Services, Inc. 305-593-2260941-561-8200 / 800-735-5416 • Labs in the US and Canada for confirmatory drug testing after screen testing are limited.

13. What do they usually test? • Labs typically like to collect at least • 25 mL of heart blood • 10 mL of peripheral blood (RBC, WBC, Platelets) • 50-gram tissue samples of brain, liver, and kidney • SEM of RBC, WBC and Platelets Scanning electron microscope 10x to 250x (10 to 500,000 times the size) By order of magnitude (10x 100x 1000x…etc)

14. Blood from the heart

15. Medical Examiner • ME collects fluids and tissues from the body for toxicological analysis • Example: Heroin is made form morphine and when injected into bloodstream-converted back to morphine

16. Collecting Samples • Blood-most useful in toxicology-concentrations of medicines and drugs in blood relate with levels of intoxication • Urine-workplace drug testing-cannot determine if drug exerted any effect on individual at time of collection • Stomach Contents-Poison or drug ingestion cases

17. Collecting Samples • Liver-involved in drug metabolism-many drugs (opiates) concentrate in the liver and bile even when blood shows no traces • Vitreous humor-liquidin the eyeball-resistant to putrefaction (decay)-drug levels lag behind those found in blood by two hours-testing it shows concentration of toxin in blood two hours earlier

18. Collecting Samples • Hair-absorbs heavy metal (arsenic, lead) toxins-provides intoxication timeline for many of these substances • Insects-Test insects that feed on corpses for drugs

19. What do they look for? • An analyst then carries out an alcohol screening and a generalized immunoassay (concentration of drug) test, which can detect broad-based drug groups like opiates or tranquillizers. • In the event of a positive drug test, the analyst must complete a confirmation procedure, designed to ferret out the exact nature of the offending substance. • Next, a supervisor reviews the analyst's report and either approves the conclusions or requests more tests. • This whole process, barring glitches or lengthy tests for hard-to-detect drugs like neuromuscular blockers (Fentanyl/Flaxedil), could take just a couple of days ifanalysts were able to devote themselves exclusively to a well-preserved specimen.

20. Who get priority? • THE LIVING get priority. • Deceased people get lower priority because their life does not depend on it. • Many times a toxicology report will be screened for unknown substances so that a cure can be given to a victim • Data needed for court date may have higher priority

21. Natural Death • Ex. Coronary artery disease (CAD) takes cocaine-heart rate increases-heart attack- • Cause of Death-heart attack • Contributory factor-cocaine • ME-extent of heart disease, amount of drugs present,whether heart attack occurred • If amount of drug is low-severely distressed arteries-natural death • If amount of drug is high-CAD is mild-accidental

22. Accidental Death • Accidental poisonings-common in children • Dose miscalculations or mixtures of drugs-mixing prescription sedatives and alcohol

23. Suicidal Deaths • Suicide-most common manner of death in poisonings-carbon monoxide-most common • Prescription drugs • CULT SUICIDES • 11-18-78 (918) People’s Temple- Jonestown, Guyana “Don’t drink the KoolAid” • 3-26-97 (39) Heaven’s Gate- San Diego, CA ingested Arsenic in pudding…

24. Homicide Deaths • Homicidal poisonings are uncommon • Determining poisoning to be cause of death-difficult task

25. POISON A substance taken in sufficient quantity to cause ill health or death

26. Specimens for Analysis • Adipose Tissue Insecticides, Thiopental • Bile Codeine, Morphine • Blood Alcohols, CO • Brain Volatile Poisons • Kidney Heavy metal • Liver Most Toxicants • Lung Methadone, Gases, Inhalants • Stomach/Intestine Contents All toxicants taken orally • Urine Most Toxicants • Vitreous Humor Digoxin, electrolytes, glucose

27. ELISA TemplateEnzyme-Linked Immunosorbant Assay • Uses antibodies and enzymes to bind to drug of interest • Qualitative, not quantitative • Specific

28. Well Plates • Come pre-coated with specific drug antigens • Add sample • Add conjugate, incubate • Antibody-enzyme complex that binds primary antibody • For drug testing, drugs will occupy that spot so the conjugate cannot bind • Wash plate, add substrate (produces color change if bound to conjugate) • Add stop, stops reaction from continuing, read plate with UV-Vis

29. Results: • A clear well indicates the presence of the drug (The drug bound to the plate, prevented conjugate from binding so substrate couldn’t bind and produce a color change) • A yellow well indicates the absence of the drug (conjugate bound to plate, substrate bound and produced color change) • Negative Calibrators, +/- Controls, and Cutoff Calibrator

31. Interpreting Drug Tests • Need to know if drug caused or contributed to victim’s death • Route of entry of toxin-concentration of drug is greatest at site where it’s administered

32. Interpreting Drug Tests • Ingested Toxins-in stomach, intestines, liver • Inhaled gases-lungs • IM Injected Toxins-Drugs most concentrated around injection site • IV Drugs-enter bloodstream directly-high concentrations in blood, but none in stomach or liver

33. Toxicologists • Know the chemical makeup, physiological actions, and byproducts of drugs • Understand how drugs are metabolized in the body and the potentially toxic properties of those metabolites • Know how these chemicals affect healthy people and people with addictions or illness • Recognize the symptoms from the drugs

34. Alcohol • Ethanol-drinking alcohol-most commonly abused drug • Blood-alcohol levels-relate to degree of intoxication-grams percent-number of grams of alcohol in every 100 ml of blood • 0.08-is the illegal limit for intoxication • 0.40-lethal level

35. CIRRHOSIS-irreversible damage to a vital organ or tissue • Alcohol causes cirrhosis of the liver

36. Cirrhosis is A condition in which the liver slowly deteriorates and malfunctions due to chronic injury. Scar tissue replaces healthy liver tissue, partially blocking the flow of blood through the liver. Scarring also impairs the liver’s ability to • control infections • remove bacteria and toxins from the blood • process nutrients, hormones, and drugs • make proteins that regulate blood clotting • produce bile to help absorb fats—including cholesterol—and fat-soluble vitamins

38. ALCOHOL'S TRIP THROUGH THE BODY • 1 MOUTH: Alcohol is consumed. • 2 STOMACH: Alcohol gets right into the stomach. A little of it goes through the wall of the stomach and into the bloodstream but most of the alcohol goes down into the small intestine. • 3 SMALL INTESTINE: Most of the alcohol then goes through the walls of the intestine and into the bloodstream. • 4 BLOODSTREAM: The bloodstream then carries the alcohol to all parts of the body, such as the brain, heart and liver. • 5 LIVER: As the bloodstream carries the alcohol around the body, it carries it through the liver. The liver changes the alcohol into water, carbon dioxide, and energy-oxidation. The liver can oxidize (change) only about one-half ounce of alcohol an hour, or .015%. This means that until the liver has time to oxidize all of the alcohol, the alcohol keeps on passing through all parts of the body, including the brain. • 6 BRAIN: Alcohol goes to the brain almost as soon as it is drunk. The bloodstream carries it there. It keeps passing through the brain until the liver has had time to oxidize all the alcohol.

45. Tests for Alcohol • Field Sobriety test-stand on one foot, stand with eyes closed, walk straight line • Breathalyzer test-alcohol passes unchanged through lungs-going to bloodstream into air sacs of lungs • Breath test related directly to blood-alcohol level • GC –to determine blood-alcohol level

47. Breathalyzer Test • Breath is exposed to water, silver nitrate in sulfuric acid, and potassium dichromate • Alcohol in the air oxidizes into acetic acid-destroying potassium dichromate in proportion to the amount of alcohol • Spectrophotometer-measures absorption of light wavelength by remaining potassium dichromate • As potassium dichromate is destroyed-amount of light it absorbs decreases • Spectrophotometer measures this change and the degree of change relates to the amount of alcohol in the breath

48. Schematic diagram of a Breathalyzer Courtesy Draeger Safety, Inc., Breathalyzer Division, Durango, Colo.

49. Figure 6-9To use this diagram, lay a straightedge across your weight and the number of ounces of liquor you’ve consumed on an empty or full stomach. The point where the edge hits the right-hand column is your maximum blood-alcohol level. The rate of elimination of alcohol from the bloodstream is approximately 0.015 percent per hour. Therefore, to calculate your actual blood-alcohol level, subtract 0.015 from the number in the right-hand column for each hour from the start of drinking.

50. Figure 6-12  The combination of the gas chromatograph and the mass spectrometer enables forensic toxicologists to separate the components of a drug mixture and provides specific identification of a drug substance.