1. Toxicology
The Study of Poisons

2. Alcohol Testing
Blood – mL of blood should be obtained (officer must be careful NOT to use alcohol to clean the syringe or the area of skin from which the sample is drawn).
Urine – Subject should first void the bladder, then provide a 25-mL sample after 20 minutes
Breath – Tested in the field (breathalyzer)

3. Samples (blood or urine) are generally tested by gas chromatography (GC)
Small sample is injected into GC and is immediately vaporized.
A carrier gas (nitrogen or helium) moves sample through tube (column).
Constitiuents of mixture (blood or urine) exit the column at different times. A peak on the GC chart shows the presence and level of alcohol in the sample.

5. Drugs
Sample is separated into acidic (barbiturates, aspirin) and basic (amphetamines, cocaine, methadone, PCP) “fractions.”
Thin-Layer Chromatography or Gas Chromatography is performed
Immunoassay – specific antigen-antibody reactions (like blood typing)
GCMS is preferred

7. Poisons in Death Investigations
Samples are collected:
3 ounces of blood (no preservatives) – taken from both chambers of heart
All stomach contents (sometimes stomach itself)
½ of the liver
Both kidneys
All urine from bladder
½ of the brain (entire brain if volatile poison is suspected)
Both lungs if volatile poison is suspected
Spleen if cyanide is suspected

8. Circumstances that May Point to Poison
If body is skeletonized: hair, nails, bones
Medicines or other substances found near victim
Cups, glasses, and other containers
Circumstances that May Point to Poison
Corrosion or burns about the mouth
Presence of drugs or paraphernalia
Victim being a “burden” on others – makes him/her a target