toxicology

1. Forensic ToxicologyForensic Toxicology
- the study of the chemical and physical properties
of toxic substances and their physiological effect on
living organisms

2. Three Primary ResponsibilitiesThree Primary Responsibilities
1. Postmortem Drug Testing
2. Workplace Drug Testing
3. Identification of Contraband Materials

3. Deaths Investigated by ToxicologistsDeaths Investigated by Toxicologists
1. Accidental Poisonings
2. Drug Abuse Cases
3. Suicidal Poisonings
4. Homicidal Poisonings

4. Deaths Investigated by ToxicologistsDeaths Investigated by Toxicologists
1. Accidental Poisonings
2. Drug Abuse Cases
3. Suicidal Poisonings
4. Homicidal Poisonings

5. Toxicological Analysis of TissueToxicological Analysis of Tissue
a. Collect sample of all body fluids
b. Collect samples from organs and tissues
c. A forensic toxicologist cannot simply look for
the presence of a toxin or drug in a body, she
must understand how the body processes these
molecules
d. Toxicological analysis must start as soon as
possible after a person’s death

6. Toxicological Analysis of TissueToxicological Analysis of Tissue
a. Collect sample of all body fluids
b. Collect samples from organs and tissues
c. A forensic toxicologist cannot simply look for
the presence of a toxin or drug in a body, she
must understand how the body processes these
molecules
d. Toxicological analysis must start as soon as
possible after a person’s death

7. General Classes of PoisonsGeneral Classes of Poisons
1. Gases
2. Metallic Poisons
3. Volatile Organics
4. Non-volatile Organics
- the major category here is what is known as an alkaloid, a
drug that mimics human neurotransmitters or hormones
and therefore interferes with normal body chemistry
Alkaloids are derived from plants…

8. AlkaloidsAlkaloids
Common Examples:
• Amphetamines – stimulants that provoke euphoria; these
drugs mimic catecholamines in the human body (adrenaline,
etc)
• Cocaine – natural stimulant that acts as a mimic to
catecholamines; metabolites are detected in urine for as
many as 3 days
• Opiates – depressants that reduce muscle activity, heartbeat,
respiration, and the inclination to sleep; effective pain
relievers and euphoria producing; opiates mimic endorphins
in the human body
• Cannabinoids – fast acting plant alkaloid; body mimic is
unknown; metabolites can be detected in urine for months

9. AlkaloidsAlkaloids
adrenaline
amphetamine
cocaine
ecstasy
serotonin

10. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

11. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

12. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

13. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

14. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

16. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

17. Example UV-vis Spectrum

18. Methods of DetectionMethods of Detection
1. Color test
2. Microdiffusion test
3. Chromatography
a. thin-layer chromatography (TLC)
b. gas chromatography (GC)
c. high performance liquid chromatography (HPLC)
4. Spectroscopy
a. UV light d. X-ray
b. visible light e. infrared
c. microwave

19. Example IR Spectrum

20. Methods of DetectionMethods of Detection
5. Mass Spectroscopy
6. Immunoassay

22. Methods of DetectionMethods of Detection
5. Mass Spectroscopy
6. Immunoassay

23. Interpretation of FindingsInterpretation of Findings
1. Is a drug or poison present? What substance?
2. How much of the substance is present? Is it’s
concentration in the body sufficient to cause
death?
3. How was the drug/poison administered?