Substances that kill at high doses are actually beneficial at low doses Arsenic – growth deficiency without it,

syphilus, cancer Clostridium botulinum - Botox

Earliest use of poison was for Socrates’ execution in 339 BC

Arsenic was most common because it left no trace and resembled death by natural causes.

“Traite des poisons” by Mathieu Orfila in 1814 gave first systematic approach to identifying poisons in the body.

James Marsh developed test to detect arsenic in body tissues and fluids.

Dosage Chemical or physical form of substance How it enters the body Body weight and physiological

conditions of the victim, age, and sex Time period of exposure Whether other chemicals are present

(synergism and antagonism)

Use animals to get estimatesLD50 is the lethal dose for half of the

population within 4 hours (mg substance/kg body weight)

Regulatory agencies FDA, EPA, Consumer Product Safety

Commission, DOT, OSHA

Subtle brain damage, memory loss, faulty thought processes

Most common exposure is through lead-based paints (banned in 1978)

2 tests for lead Reaction of dissolved lead with sulfide ion

to form insoluble, brown-black lead sulfide Reaction with an organic complexing agent,

sodium rhodizonate, to make a pink color Other sources: lead pipes, soil, leaded

gas (banned in 1995)

Less than one half of 1% of all homicides are a result of poison

Common poisons today are arsenic, cyanide, and strychnine

Acute poisoning – high dose over short period of time

Chronic poisoning – low dose over long amount of time

More common than poisonings John Belushi, Chris Farley, River Phoenix,

Janis Joplin, Jim Morrison, Jimi Hendrix, Marilyn Monroe, Heath Ledger, Anna Nicole Smith

Organic - Venom Snakes, bees

AlcoholsBacterial Toxins

Botulism (neurotoxin), Clostridium tetaniHeavy Metals and PesticidesBioterrorism Agents

Ricin (waste product of castor oil) Anthrax (Bacillus anthracis)

Most abused drug in America 40% of all traffic deaths are alcohol

related Ethanol affects the CNS BAC ist he amount of alcohol in the

blood Present BAC limit is 0.08% so .08 grams

of alcohol for every 100 mL of blood Average removal rate is 0.015% per

hour

BAC (male) = 0.071 x (volume consumed, oz) x (% alc.)/body weight

BAC (female) = 0.085 x (volume consumed, oz) x (% alc.)/body weight

1 mL of blood contains as much alcohol as 2,100 mL of breath (based on Henry’s Law)