 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 estimates  LD50 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  Alcohols  Bacterial Toxins  Botulism (neurotoxin), Clostridium tetani  Heavy Metals and Pesticides  Bioterrorism 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) = x (volume consumed, oz) x (% alc.)/body weight  BAC (female) = 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)