1. Forensic Toxicology

2. Toxicologist  An individual charged with the responsibility of detecting and identifying the presence of drugs and poisons in body fluids, tissues, and organs

3. Not only for death investigations  Hospitals labs for drug overdoses  Blood tests on children for exposure to lead  Examine urine of addicts

4. Toxins  Any material exerting life threatening effects upon a living organism  A toxin is a poisonous substance produced by a living organism  Poisons are a subcategory of toxins

5. Toxins vs Poisons  May enter the body in different ways.  Work in low quantities or low levels  Easy to detect  If treatment is early, the person can be saved.  Normally enter in a single massive dose  Normally are found in huge doses.  Hard to detect  People often die because the reason for illness is not detected soon enough.

6. Dose-Response Relationship  Relationship between the amount of a substance that a human would be exposed to and the relationship to their body after exposure.

7. Lethal Dose  Lethal dose is the dose taken that would cause death to the organism  To determine the Lethal Dose scientists test two different animals and two different methods of exposure (one being the way humans would take the substance)

8. Lethal Dose  In a lethal dose study, scientists will study how much will have to be given to the two different animals in order to cause death.  Animals in these studies normally die within 14 days and scientists can take their results from these tests and relate them to human beings.

9. Most heavily abused substance is legal!!  Ethyl Alcohol  40% traffic deaths  17,500 fatalities a year  2 million injuries a year

14. Toxicology of Alcohol  Metabolism- the transformation of a chemical in the body to other chemicals for facilitating its elimination from the body  3 steps  Absorption  Distribution  Elimination

15. Absorption  Alcohol appears in the blood minutes after consumption and increases in concentration while it is being absorbed from the stomach and small intestine into the bloodstream.  Absorption= the passage of a substance across the wall of the stomach and small intestine into the blood stream

16. What affects rate of absorption  How long it takes to consume a beverage  Alcohol content of beverage (proof)  The amount consumed  Food present in stomach

17. Distribution of Alcohol  Bloodstream  BAC tests performed

18. Elimination  Oxidation- 95-98% of the alcohol undergoes this chemical process which converts alcohol to carbon dioxide and water. Occurs in liver.  Elimination- 2-5% is excreted by perspiration, urination, and breathing

19. Breathalyzer Test  The amount of alcohol exhaled in the breath is in direct proportion to the concentration of alcohol in the blood.

20. Elimination varies with individual  Weight  Muscle tone or physical condition  History with drug (tolerance)  Metabolism  Age

21. Blood Alcohol concentration

22. Blood Alcohol Content  Most accurate test  Requires blood

23. Absorption  20% absorbed by the stomach  80% by small intestines  All alcohol is broken down by liver  Arteries will have a higher BAC than veins during absorption  Blood tests retrieve blood from veins

24. Testing for intoxication  BAC not convenient for traffic officers  Breath testing performed  Breathalyzer  Developed 1954 by R.F. Borkenstein  Uses chemicals to detect BAC

25. Fuel Cell detector  A chemical reaction involving alcohol produces electricity  Will give officer a digital readout of BAC

26. Errors in detection  Police are supposed to ensure no foreign material is in mouth for 15 minutes before test  Regurgitation (throwing up)  Belching  Recent Drinking  Gargling with an alcohol based mouthwash

27. Field sobriety tests  Deal with physical impairments  Stand on one leg  Walk straight line  Horizontal gaze nystagmus  Walk heel to toe

28. Alcohol and the law  1992 US Department of Transportation (DOT) required states adopt 0.08% BAC  Made federal law in 2000  If an individual exceeds.08% they are deemed “intoxicated”  In 2003 states that did not abide with this law lost federal funding for highway construction

29. Alcohol and the law  Commercial drivers such as bus or 18 wheelers must not exceed.04 % BAC

30. Is it constitutional??  5 th amendment states that you have the right to not incriminate yourself  Driving is a privilege not a “right” so they may take away your license for refusing to test (6 months-12 months)

31. Role of the Toxicologist  Generally there are few signs that indicate what type of poison in system  Clues arise from  Medicine bottles  Household chemicals  Postmortem pathological examination

32. Toxicologist must  Work with nanograms and micrograms of specimen due to absorption of body  Pure samples are easier to analyze  The body metabolizes each substance differently  Example- heroin is almost immediately broken down to morphine in the body  Toxicity levels vary by individual

33. Toxicologist handles  Blood (a minimum of 10 ml required)  Urine

34. 90% of the drugs encountered in a toxicology lab are:  Cocaine  Alcohol  Marijuana

35. Acid/Base Tests  Toxicologist can extract acidic drugs from acidified water using chloroform  Basic drugs can be extracted using basic water solutions and organic solvents

36. Drugs  Acidic  Barbituates  Aspirin  Basic  Phencyclidine  Methadone  Amphetamines  Cocaine

37. Famous cases  1982 Tylenol was tampered with in Chicago. Someone opened up the gels capsules and replaced drug with potassium cyannide  7 deaths  $100,000 reward from tylenol for information

38. Toxicology of hair  Most drugs leave bloodstream within 24 hours. Urine tests are accurate up to 72 hours on average  Drugs present in blood diffuse through capillary walls into the base of hair and become permanently entrapped in the protein structure

39. Toxicology of hair  As the hair grows, the drugs location on the hair shaft becomes a historical marker for drug intake  Human hair grows an average of 1 cm a month

40. Nondrug poisons  Heavy metals- Substance is placed in HCl with a copper strip. Silver or dark coating means presence of heavy metal. Confirmation tests necessary.  Arsenic  Bismuth  Lead  Antimony  Mercury  Thallium

41. Nondrug poisons  Carbon Monoxide (CO)  Suicide by car- usually a vacuum hose or garden hose in tailpipe to stream gas into car. 5-10 minutes in single car garage with car running is sufficient for death  Also seen in fires.

42. Drug Recognition Experts  3-5 month Training  Can suggest if victim/offender exhibited behaviors associated with:  CNS depressants  CNS stimulants  Hallucinogens  Dissociative Anesthetics (phencyclidine)  Inhalants  Narcotic Analgesics  Cannabis