1. Toxicology
(Impact of poisons)

3. Hazards Biological – pathogens (diseases), pollen, animals
Cultural – Smoking, diet, drugs
Physical – natural disasters
Chemical :
Mutagens – alter DNA
Teratogens – cause birth defects
Carcinogens – cause cancer

4. Biological Hazards
Nontransmittable disease: Any disease that cannot be spread directly from one person to another
Transmittable Disease: Any disease that can be spread directly by person or living organism
Chronic conditions like heart disease or diabetes
Can be spread by bacteria, protozoan, or virus
Acute conditions like influenza, HIV, strep throat, smallpox

5. 6 deadliest infectious diseases
Acute respiratory infections (pneumonia and flu)
HIV/AIDS
Diarrheal diseases (typhoid fever, rotavirus)
Tuberculosis
Malaria
Measles

6. Spread of transmittable disease
Air travel
Migration to urban areas and rural areas
Hunger/malnutrition/water access
Increased rice cultivation
Increased water exposure
Accidental introduction of insect vectors (Vectors carry disease – ticks, fleas)
Migration – which disease is prone to develop in each area

7. Leading causes of death
In developing countries, infectious disease (AIDS, malaria, flu,)
In developed countries = chronic conditions (heart disease)

8. Toxicology Toxicity – measure of how harmful a substance is
Toxic if it kills 50% of test population
Hazardous – causes harm
Harmfulness depends on several factors:
Dosage over time
Exposure
Who is exposed
How well body’s detox systems work
Genetic makeup to determine sensitivity to a toxin

9. Other ways harm can be caused by a substance
Solubility :
Water soluble toxins = water supplies
Oil or fat soluble toxins = body tissues and cells
Persistence
How long substance remains in toxic form in environment

10. Bioaccumulation / biomagnification
Bioaccumulation – accumulation of a toxin within tissues of a lower organism in a food chain
Biomagnification – exposure to higher levels of toxins by consuming toxins from multiple prey organisms

11. Interactions Antagonistic interaction – reduce harmful response
Ex. Vitamins E and A interact to reduce body’s response to carcinogens
Synergistic effect – multiplies harmful effect
Alcohol and prescription meds

12. Response Response = type and amount of health damage due to exposure
Acute effect – immediate/rapid harmful reaction to an exposure (allergic reaction)
Chronic effect – permanent or long lasting consequence (liver or kidney damage from drinking for 10 years)

13. Poison
The LD50 is the median lethal dose or the amount of a chemical received in one dose that kills 50% of test population in a 14 day period
The LC50 is the concentration of chemical that would kill 50% of the test population in 14 days
**Don’t write** - the AP exam will present these as the same thing

14. Some example toxicities (Do not write)
Nerve gas – less than one drop
Morphine – 7 drops to 1 tsp
Aspirin – 1 ounce to 1 pint
Water – essentially nontoxic, but too much would kill you
For me – 2133 cups of decaf coffee, 265 cans of Coke Zero, Hershey’s Kisses

15. Dose Response Curve – shows dosage affect on group

16. Dose Response Curve
Nonthreshold –any dosage of a toxic chemical will cause harm that increases with dosage
Threshold dose-response model – there is a threshold or a line before any detectable damage can occur (b/c body can combat to an extent)