1. CH 11 RISK, TOXICOLOGY and HUMAN HEALTH • 21.1 What is Risk? Probability that _______ • Diff b/n risk assesment and risk managemnt • Risk assesment-__ • Risk management- __ • B. Types of hazards (4) ______

2. 21.2 Toxicology • What determines if chemical is harmful? ______ and _______! • 1. _____-amt of substance person is exposed to depends on size of dose, freq, who, genetics. • chemical interactions that occur (2 types) • a. antagonistic interaction- b. synergistic interaction- • 2. _____-type and amount of health damage ….acute vs chronic • Ex. Thalidomide

3. B. Should we be concerned about trace levels? Natural vs synthetic dangers? C. Biomagnification or Bioaccumulation?

4. D. What is LD50? ________________ (fig 11-5)

5. Dose Response Curves-show effects of various dosages of a toxic agent on organisms Can we rely on these tests and extrapolate to humans?

6. 11-3 Hazardous Chemicals Toxic chemicals-fatal to 50% of animals. Haz. Chemicals cause harm b/c 1. ____ 2.___3.____4. _____ Mutagens- ex. Bipolar, CF, hemophilia, sickle cell, down syndrome, some cancers Teratogens- ex. PCBs, thalidomide, steroid hormones, heavy metals. Carcinogens-

7. Endocrine disrupters- Precautionary Principle-