Forensic Toxicology

Father of Modern Toxicology

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

Forensic Toxicology

"All things are poison and nothing is without poison,

only the dose permits something not to be

poisonous.”-Paracelsus

Toxicology

• What is it??– Analysis of biological fluids for the presence of

controlled substances, common pharmaceuticals and poisons.

• What do Toxicologists know?– All about drug interactions, metabolism,

therapeutic vs. toxic doses, and impairment

Toxicology

Antemortem = before death

• DUIs• Drug Facilitated Sexual

Assault• Workplace Drug Testing• Parole violations

Postmortem = after death

• Homicides • Suicides• Overdose (intentional v.s.

accidental)• MVA (motor vehicle

accident)• Unexplained death• Natural (sometimes)

Types of Samples

• Blood• Urine• Vitreous humor• Gastric contents• Tissue: Liver, Spleen, Brain• Maggots

Summary of Drug Categories• CNS depressants

• CNS stimulants

• Narcotic Analgesics

• Cannabis

• Hallucinogens

• Dissociative Anesthetics

Combinations of Drugs

What is the most common combination of drugs in postmortem tox cases?

What is the most common combination of drugs in antemortem DUII cases?

What is the most common drug identified in Drug-Facilitated Sexual Assault cases?

Sample prep:Solid Phase Extraction (SPE)

Sample collection tubes

Gas chromatograph/Mass spectrometer

1. Autosampler

2. Injection port

3. Oven/column

4. Mass spec

5. Data analysis

Case 1: Challenge from beyond the grave

• 24 year old male; suspected suicide

• Note:

“CSI: Save your time and money. I did not use drugs or alcohol.”

Case 1: Challenge from beyond the grave

• Results (Blood):

Ethanol 0.00 g/dL

Nortriptyline 0.889 mg/L

Methamphetamine 0.189 mg/L

Amphetamine 0.113 mg/L

Hydrocodone 0.030 mg/L

Carboxyhemoglobin 1.7 %

Results (Gastric):

Nortriptyline

Case 2:Decomposed = limited sample options

• 47 year old male• Recovered from Willamette river• Significantly decomposed• Liver & spleen submitted for

analysis

LiverQuickTime™ and a

decompressorare needed to see this picture.

Spleen

QuickTime™ and a decompressor

are needed to see this picture.

Homogenization of liver

Case 2:Decomposed = limited sample options

Results (Liver):

Methamphetamine: 1.58 ug/g

Cannabinoids: Indicated

Case 3:Highest Postmortem BAC

• Female, 42

• Chronic alcoholic

• Drank vodka, went to sleep

• Found by family several hours later

• Rx for lithium, lorazepam, diazepam

Case 3:Highest Postmortem BAC

Results (Blood):

Ethanol: 0.63 g/dL

Lorazepam: 0.050 mg/L

Case 4: Fentanyl

• Female, 56

• Found in hot tub wearing multiple fentanyl patches

Case 4: Fentanyl

Results (Blood):

Blood Fentanyl concentrations in fatal cases:

3.0 – 28 ng/mL

Disposition of Toxic Drugs and Chemicals in Man, 5th ed.

Fentanyl : 49 ng/mL

Fentanyl

Case 5: Choking or OD?

• Male dies; friends allege he choked on steak

• Overdose was suspected

Case 5: Choking or OD?

• Results (Blood):

• Blood Methamphetamine average in fatal cases:

0.96 mg/L (Logan et al, 1998)

Methamphetamine: 1.22 mg/L

Amphetamine: 0.099 mg/L

Fire, auto exhaust, & hibachi

Fire, auto exhaust, & hibachi

•Fire deaths

•Was the individual deceased prior to the fire?

•Found in vehicle

•Suicide by auto exhaust?

•Found in small room (bathroom) with charcoal grill or hibachi

•Suicide by CO inhalation?

Carboxyhemoblobin (COHb)

1 – 5% Environmental, Smoker

15 – 35% Toxic

> 50% Lethal

% COHb

Case 6: Non-compliant diabetic

• Vitreous electrolytes and glucose

• Typical vitreous glucose: 0 – 150 mg/dL

• Glucose > 1000 mg/dL

Case 6: Non-compliant diabetic

GC-FID

Blood Ethanol Analysis

•Ethanol (quantitated)

•Methanol

•Isopropanol

•Acetone

•Acetaldehyde

Pills in gastric contents