Forensic Toxicology

Intoxicant

Requires large quantities to do harm

Alcohol

What is an example of an intoxicant

What defines a true poison

requires only a tiny amount to do harm

Botulism

What is an example of a poison

less than half of 1% of all cases

how commonly used is poison in murders

bodily fluids (blood, urine), tissue, organs, & hair

Where might toxicologists look to detect drugs and/or poisons

they must identify, quantify, and assess toxicity

Once a poison or drug is detected, what is the role of the toxicologist?

ingestion, inhalation, injection, absorption

What are the four methods of exposure for a poison/toxin?

Injection

Which method of exposure provides the quickest systemic reaction to the toxin?

Drugs in the body are absorbed into the blood

What is the first stage of physiological processing of a poison?

drugs are distributed throughout the body by the blood stream

What is the second stage of physiological processing of a poison?

drugs are broken down or metabolized

What is the third stage of physiological processing of a poison?

metabolized products are eliminated from the body through the liver & kidney

What is the fourth stage of physiological processing of a poison?

1. normal

amount of a toxin that would be expected to be in your system

2. Therapeutic

amount a toxin that might be prescribed by a doctor

3. Toxic

amount of a toxin that consistently causes harm

4. Lethal

amount of toxin that consistently causes death

calculated dose of a substance that kills 50% of a test population, usually within 4 hrs.

What is LD50?

physiological factors – weight, metabolism, age

what is the first factor that might affect the levels of toxicity?

dosage & duration

what is the second factor that might affect the levels of toxicity?

method of exposure

what is the third factor that might affect the levels of toxicity?

interaction of the toxin with other substances in the body

what is the fourth factor that might affect the levels of toxicity?

acute poisoning

 high dose over a short period of time

chronic poisoning

lower dose over long periods of time.

presumptive test

 a quick test to narrow down possibilities

confirmatory test

a test that determines exact identity of toxin

Animals

what is one source of Poisons/toxins from an organic source?

Plants

what is a second source of Poisons/toxins from an organic source?

Bacteria

what is a third source of Poisons/toxins from an organic source?

Minerals

what is a one source of Poisons/toxins from an inorganic source?

Carbon Monoxide

what is a second source of Poisons/toxins from an inorganic source?

Heavy Metals

what is a third source of Poisons/toxins from an inorganic source?

Hemotoxins

destroys red blood cells

neurotoxins

affects the nervous system

necrotoxins

kills cells and tissues

potential for abuse

The federal Controlled Substances Act of 1970 recognizes five Schedules of drugs. What is one factor the government use to determine which Schedule a drug should placed on?

potential for dependence

The federal Controlled Substances Act of 1970 recognizes five Schedules of drugs. What is a second factor the government use to determine which Schedule a drug should placed on?

medical value

The federal Controlled Substances Act of 1970 recognizes five Schedules of drugs. What is a third factor the government use to determine which Schedule a drug should placed on?

Schedule 1 drugs have the highest potential for both abuse and dependence and Schedule 5 drugs have the lowest.

In terms of potential for abuse, medical value, and dependence, what is the difference between a drug that is on Schedule 1 vs. Schedule 5?

allows the body more time to metabolize and eliminate alcohol, reducing overall BAC.

 how does the timing in between drinks affect your BAC?

Doing this before or while drinking can slow down the absorption of alcohol into the bloodstream

how does eating affect your BAC?