1. Toxicology: Poisons and Alcohol
Chapter 8
Toxicology: Poisons and Alcohol
“If all those buried in our cemeteries who were poisoned could raise their hands, we would probably be shocked by the numbers.”
—John Harris Trestrail, Criminal Poisoning
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2. Kendall/Hunt Publishing Company
Chapter 8
Toxicology
Toxicology—the study of the adverse effects of chemicals or physical agents on living organisms
Types of Toxicology:
Environmental—air, water, soil
Consumer—foods, cosmetics, drugs
Medical – ER, poisonings, drugs
Forensic –
Postmortem—medical examiner or coroner
Criminal—motor vehicle accidents (MVA)
Workplace—drug testing
Sports—human and animal
Environment—industrial, catastrophic, terrorism
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3. Kendall/Hunt Publishing Company
Chapter 8
Toxicology
Acute: immediate effects of toxins (i.e. death)
Chronic: long-term effects of toxins (i.e. cancer)
Synergism: The combination of drugs can have magnified effects. For example: a person takes barbiturates and drinks alcohol and then dies. By themselves, the drugs wouldn’t have killed the person, but taken together they have a lethal effect.
Antagonism: Combined effect of substances that decreases their individual effects (opposite of synergism)
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4. Symptoms of Various Types of Poisoning
Chapter 8
Symptoms of Various Types of Poisoning
Type of Poison
Caustic poison (lye)
Carbon monoxide
Sulfuric acid
Hydrochloric acid
Nitric acid
Phosphorus
Cyanide
Arsenic, mercury
Isopropyl (rubbing) alcohol
Symptom/Evidence
Burns around the lips and mouth
Red/pink patches on the chest & thigh
Black vomit
Greenish-brown vomit
Yellow vomit
Coffee-brown vomit, onion or garlic odor
Burnt almond odor
Extreme diarrhea
Nausea, vomiting, unconsciousness, blindness
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5. Drug Intake and Absorption
Drug Intake: swallowing powders, tablets, capsules; inhaling vapors; injection with a syringe
Absorption: Once a drug has entered the body, it is absorbed into the bloodstream and circulated throughout the body. Some drugs tend to concentrate in certain areas:
Pesticides in fatty tissue
Heavy metals: teeth, gums, hair
LSD and marijuana: brain

6. Addiction vs. Dependence
Chapter 8
Addiction vs. Dependence
Tolerance: Occurs when increasing doses are required to keep the same level of effects on the person. If a person tries to quit a drug, withdrawal symptoms can sometimes be fatal because the body has become dependent on the drug.
Drug addiction: physical process. Biochemical changes occur in the body to help tolerate the drug.
The body may then require the drug on a regular basis.
If the drug is not used, withdrawal symptoms may occur: sleeplessness, restlessness, nausea, hallucinations, headaches
Dependence: psychological craving for the drug. Withdrawal symptoms do not occur if drug use is stopped.
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7. Kendall/Hunt Publishing Company
Chapter 8
Lethal Dose
LD50 refers to the dose of a substance that kills half the test population, usually within four hours
Expressed in milligrams of substance per kilogram of body weight
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8. Elimination of Drug From Body
Half-life: time it takes for the concentration of a drug to drop to half of its concentration
Cocaine’s half-life: minutes
Heroin’s half-life: 3 minutes
Liver: can change a drug into a different substance, forming a metabolite.
For example, the metabolite of heroin is morphine.
Toxicologists often look for metabolites when trying to detect drugs
Elimination of Drugs From Body:
Exhaled in breath
Sweat
Urine

9. Alcohol—Ethyl Alcohol (C2H5OH)
Chapter 8
Alcohol—Ethyl Alcohol (C2H5OH)
Most abused drug in America
About 40% of all traffic deaths are alcohol-related
Depressant
Alcohol appears in blood within minutes of consumption; 30–90 minutes for full absorption
Detoxification—about 90% in the liver
About 5% is excreted in breath, perspiration, & urine
Neurotoxin: kills nerve cells (one ounce of ethanol can kill about 10,000 nerve cells)
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10. BAC: Blood Alcohol Content
Chapter 8
BAC: Blood Alcohol Content
Expressed as percent weight per volume of blood (grams of alcohol present in 100mL of blood)
Legal limit in all states is 0.08%
Parameters influencing BAC:
Body weight/physiology of consumer
Alcohol content of beverage
Number of beverages consumed
Time alcohol is consumed within
Quantity & type of food consumed
Time since consumption
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11. Blood Alcohol Concentration (BAC)
BAC and effects:
0.04: feeling of relaxation
0.06: less able to make rational decisions
0.08: impairment in motor coordination skills (driver intoxication)
0.12: vomiting
0.40: loss of consciousness
0.45: death

12. Drunk Driving Laws
Implied Consent: when you sign your driver’s license you are giving consent that you will submit to a blood or breath test if you are stopped for drunk driving.
Refusal to submit can result in the loss of your license for days.
Field Sobriety Testing: walk and turn, stand on one foot, horizontal gaze nystagmus (eyes watch a pencil as it moves)