1. Forensic Toxicology

2. Toxicology Definition: Analysis of body fluids or tissues for the presence of 1) controlled substances, 2) common pharmaceuticals and 3) poisons. What do Toxicologists know? –All about: drug interactions, metabolism, therapeutic vs. toxic doses, and impairment

3. Challenges… Identify 1 in 1000 drugs/poisons needle in a haystack Find tiny (nanogram to microgram) quantities, through the entire body Not always looking for exact chemicals …metabolites are breakdown products Examples: heroin  morphine in seconds THC  THC-9 in urine

4. Forensic Toxicology Father of Modern Toxicology… Orfila

5. Paracelsus "All things are poison and nothing is without poison, only the dose permits something not to be poisonous. ” (1530 AD)

6. Toxicology…when do we do it ?? Antemortem = before death DUIs BREATH Drug Facilitated Sex.Asslt. BREATH, URINE Workplace Drug Testing BREATH, URINE Parole violations BREATH Post mortem = after death Homicides Suicides Overdose MVA Unexplained death Natural (sometimes)

7. Toxicology of Alcohol Alcohol is absorbed into the blood, via stomach and small intestine Once absorbed, alcohol is: –Oxidized (oxidation = burned, with O 2 ) in liver –Excreted in breath and urine… AS UNCHANGED PURE ALCOHOL !!

8. Alcohol in the Circulatory System Quantity of alcohol in the blood is… …how drunk you are. Two methods of making this measurement –Measure alcohol in blood –Measure alcohol in breath

9. Circulation Con’t Ratio of blood alcohol to alveoli air is approximately 2100 to 1 –Means 2100 mL of Breath has the same alcohol as 1mL of Blood

10. The Breathalyzer

11. Breathalyzer Con’t 3 types of breathalyzers Measure alcohol in different ways –Chemical… alcohol  some other chemical –Fuel Cell… alcohol  electricity – Infrared (IR) alcohol  reflects IR back

12. Infrared and Fuel Cell Breath Tests Infrared Breath Test uses infrared wavelengths to test for alcohol Fuel Cell Test converts fuel (alcohol) and oxygen into a measurable electric current

13. Field Sobriety Testing Two reasons for the field sobriety test: 1.Assess suspects’ physical impairment 2.Determine need of evidential (urine) test.

14. Field Sobriety Tests Horizontal Gaze Nystagmus –Involuntary eye jerk as eye moves horizontally Walk and Turn (divided attention tasks) One-Leg Stand

15. Horizontal Gase Nystagmus - CLIP http://www.bing.com/videos/search?q= horizontal+gaze+nystagmus+video& view=detail&mid=95C10FAF1ABA0 3518D1A95C10FAF1ABA03518D1A &first=0&qpvt=horizontal+gaze+nyst agmus+video&adlt=strict

16. Alcohol and the Law 1939-1964: intoxicated = 0.15% BAC 1965: intoxicated = 0.10% BAC 2003: intoxicated = 0.08% BAC At least we don’t live in France, Germany, Ireland, or Japan (0.05%) or especially Sweden (0.02%)!

17. Drug Testing in the Body Urine is most common Immunoassay –Based on antigen-antibody binding specificity –Antibody produced by injecting antigen (drug) into rabbit –Antibodies will bind to drug in urine Confirmation done w/TLC

18. False positives in Immunoassays Poppy seeds and Vicks 44 for opiates Decongestants for amphetamines Benadryl and numerous cough syrups for PCP