Forensic Toxicology. William C. Bress, PhD State Toxicologist Adjunct Assistant Professor Department of Biology University of Vermont

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1 Forensic Toxicology William C. Bress, PhD State Toxicologist Adjunct Assistant Professor Department of Biology University of Vermont

2 History of Forensic Toxicology Paracelsus ( ) 1541) Orfila ( ) 1853) Dr. A.O. Gettler (1918) Dr. Abe Freireich(1937) Dr. Jesse Bidanset(1968)

3 Poisoners Motive Intent Means Opportunity Detection

4 Commonly Used Poisons Arsenic Cyanide Strychnine Morphine Chloroform

5 Poisoners Background Public Physician Political Nurse 46% male 39% female 16% unknown

6 Motive Insurance 26% Domestic 9% Political Extremism 7% Personal Cause 11% Other, Unknown 29%

7 Crime Scenes Where was victim found Where was poison administered Where was poison disposed Where was poison prepared Where was poison procured Most poisonings committed by one person

8 Crime Scene cont. Odors? Vomiting? Evidence of Staging Residue, bottles, beverages, food, receipts Victim rarely exhibits signs of external violence

9 Poisoners 1865 Edward Willliam Pritchard, MD, used antimony 1881 George Henry Lamson, MD, The Slight of Hand, Poisoner aconite 1891 Thomas Neill Cream, MD The Lambeth Poisoner strychnine

10 Prisoners cont Hawley Harvey Crippen, MD Mild Mannered Murderer hyoscine? 1912 Henri Girard The First Scientific Murderer Aminita, germ cultures 1933 The Man Who Wouldn t Die, pure alcohol, horse liniment, antifreeze, carpet tacks, hypothermia, hit by car, coal gas

11 Toxicological Specimens Blood- acidic drugs (barbiturates) Brain- volatiles (ethanol) Liver- basic drugs (antidepressants) Kidney- metals Bile- opiates (morphine) Gastric- tablets Urine- drugs previously consumed

12 Drug Isolation Homogenize tissues Heat under vacuum, distill Analyze distillate for volatile drugs Filter homogenate Extract with organic solvents Strong acid, weak acid, neutrals Basic drugs

13 Drug Isolation Strong acids- salicylates Weak acids- barbiturates Neutral drugs- caffeine Basic drugs- morphine, methadone

14 Drug Extraction A compound in non-ionized form prefers the lipophilic environment of an organic solvent to the aqueous environment of the biological sample. The specimen is buffered according to the ph characteristics of the analyte of interest and mixed with an immiscible organic solvent

15 Extraction Cont. A basic drug is in it s non-ionized form in n alkaline ph, an acidic drug is in it s non- ionized form in an acidic ph. Liquid-liquid extraction is very effective but time consuming. Solid-phase extraction Hydrolysis

16 ph 6.0 blood solvent solvent ph 9.0 Weak acids neutrals ph 12.0 Weak base caffeine barbiturates morphine.1n NaOH Strong base discard strong acids amphetamine salicylates

17 Pharmacokinetics Volume of distribution Vd(L/kg) Plasma concentration Cp(mg/L) Dose A(mg/kg) Cp=A/Vd Digoxin 0.2mg dose, Vd= 7L/kg Person weighs 70 kg Plasma concentration would = 0.4ng/ml

18 Evaporation, distillation Liquid extraction

19 condition sample wash elute Solid phase extraction

20 Thin Layer Chromatography

21 Confirmation Ultra- violet spectrophotometry Infra-red red spectrophotometry Gas-chromatography chromatography-mass mass spectroscopy Liquid-liquid mass spectroscopy

22 Mass Spec

23 Cannabis

24 Cocaine Metabolites

25 Blood Levels Marihuana delta 9 THC carboxy THC 11 hydroxy THC Heroin Heroin- minutes Morphine- hours

26 Cause of Death Stomach-tablets tablets present? Blood concentration Brain concentration Liver concentration Urine concentration

27 Drug Death Blood 200ng/ml 2400ng/ml brain 150ng/ml 60ng/ml liver 2400ng/gram 34ng/ml stomach 2,000ng ND urine 350ug/ml ND Death in hours minutes

28 Driving Under the Influence Pickup truck speeding, runs off road and knocks down telephone polls on highway. Driver used cocaine for days previously Blood levels of cocaine low Was driver under the influence?

29 Ethanol Car accident time of death last drinks blood sample zero order elimination(not dependent on dose) vitreous humor

30 Interpretation Tolerance Transfusions Trauma Lidocaine Air crash Drowning

31 Celebrity Drug Related Deaths Elvis- ethinamate,, morphine, methaqualone,, codeine, barbiturates, valium and Demerol Marilyn Monroe-chloral hydrate, Nembutal John Belushi- speedball cocaine heroin