Transcript Ch 8 Poison and Alcohol

Poisons
 “The poison is in the dosing”
 Socrates: killed with hemlock: 1st recorded homicide by
poison 339 BC
 Strongest poison: botulism
 Now used to diminish wrinkles
 Toxicology: study of adverse effects of chemicals on
the body
 Level of toxicity affected by:
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Dosage
Chemical or physical form of the drug
How enters body
Body wt. and physical condition
Time period of exposure
Other chemicals in body
 Chelating agent: binds with a chemical and changes it’s
effects.
 Synergism: substances that work together
 Antagonism: substances with opposing results
 Chronic exposure: exposure over a long period of time
 Acute: over short period of time
 LD 50: lethal dose for half the test population (animals):
usually within 4 hours
 3 most lethal compounds are natural products:
 Ricin
 Dioxin
 botulin
 Government regulatory agencies:
 FDA: pharmaceuticals and food additives and medical
devices
 EPA: agricultural and industrial chem.s into environment.
 Dept. of transport: shipments of toxic materials
 OSHA: occupational safety and health admin.
Lead
 Lead paint ban in 1978
 Lead gasoline ban in 1995
 Lead leaches into the soil
 Lead leads to nervous system problems and learning
disabilities in children
Alcohol
 Alcohol (ethanol, ethyl alcohol)
 Most abused drug in the US
 Most widely used drug on college campuses
 20% of all alcohol produced is consumed by teenagers
Drink and drive
 40% of all traffic deaths involve alcohol
 Highest risk group: males 16-24 years old
 Males 2x as likely to be in MVA
 Males consume 2x as much as women
Dept of Transportation
 Significant impairment at BAC of .02 to .05
 Change reaction time
 Change time between stimulus and response
 Change stop ability by 15 to 21 feet at moderate speed
(40mph)
 .04 is legal limit for commercial vehicle operation
 .08 is legal limit for personal vehicle operation
 .15 to .20 is blood alcohol for most arrests in US
 .30 comatose
 .40 is LD 50 (lethal dose for half of people)
 .50 most references say certain death
 Myth: being intoxicated reduces your risk of injury in an
mva.
 False. Half of people that suffer traumatic brain injury
in US are intoxicated
 Can have alcohol induced cerebral edema
 Alcohol produces acidosis which can change breathing
patterns
Alcohol
 Ethanol is toxic
 Affects central nervous system, liver, digestive, skin
 Rate of absorption into blood
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Amount consumed
Alcohol content of beverage
How quickly consumed
Amount food in stomach
Other drugs in system
 90% of alcohol is processed in the liver
 Alcohol - acetylaldehyde - acetic acid – CO2 + water
 Liver processes .5ounce per hour (NOTHING will
increase this rate)
 Alcohol kills liver cells, fatty deposits, cirrhosis
 10% removed through sweat, breathe, urine
 Alcohol is a diuretic
 Absorption of alcohol start in mucus membrane of
mouth.
 90 seconds to circulate throughout body.
 Food or juice in stomach will slow absorption.
 Digestive tract:
 Alcohol irritates the lining of stomach: ulcers
 Alcohol linked to cancer of mouth, esophagus,
stomach, intestines
 Alcohol has calories and no nutritional value
 So alcoholics are malnourished and dehydrated
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Hair is dry
Lips cracked
Acne
Skin puffy
Broken veins
 Brain:
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Initially, frontal lobe: euphoric and decreased inhibitions
Then, reach cerebellum: coordination and perception
Mid brain: reflexes, confusion, stupor
Medulla: heart rate and breathing
 BAC: blood alcohol content in percent weight per
volume
 Legal limit: .08%
 .08 grams alcohol/100ml of blood
 Increase tolerance with chronic abuse:
 1 drink: 12oz beer, 5oz wine, 1oz whiskey
 Overtime develope physical and psychological
dependence: alcoholism
 BAC: Blood alcohol content
 Must consider
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Body weight
# of drinks
% alcohol in each drink
Over what time period (-.15 per hour)
Male/female (males more alcohol dehydrogenase)
 BAC: male
 .071 x (ounces consumed) (% alcohol)
 Divided by body weight
 BAC: female
 .085 x (ounces consumed) (%alcohol)
 Divided by body weight
 Metabolism (detoxify) begins almost immediately.
 Average rate of removal: .015% /hour
 Alcohol content in a liquid can be stated in “proof”
 Actual % alcohol is HALF the “proof”
 Henry’s Law:
 Alcohol concentration in breath is proportional to alcohol
concentration in the blood.
 Breathalyzer invented in 1954
 Color change with chemical reaction
 New breathalyzer: more sensitive
 Infrared spectrophotometry