Download Forensic Toxicology

Forensic Toxicology
- the study of the chemical and physical properties
of toxic substances and their physiological effect on
living organisms
Three Primary Responsibilities
1. Postmortem Drug Testing
2. Workplace Drug Testing
3. Identification of Contraband Materials
Deaths Investigated by Toxicologists
1. Accidental Poisonings
2. Drug Abuse Cases
3. Suicidal Poisonings
4. Homicidal Poisonings
Deaths Investigated by Toxicologists
1. Accidental Poisonings
2. Drug Abuse Cases
3. Suicidal Poisonings
4. Homicidal Poisonings
Toxicological 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
Toxicological 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
General 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…
Alkaloids
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
Alkaloids
amphetamine
adrenaline
cocaine
serotonin
ecstasy
Methods 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
Methods 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
Methods 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
Methods 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
Methods 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
Methods 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
Example UV-vis Spectrum
Methods 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
Example IR Spectrum
Methods of Detection
5. Mass Spectroscopy
6. Immunoassay
Methods of Detection
5. Mass Spectroscopy
6. Immunoassay
Interpretation 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?