Risk Assessment (9/13)

Question 1

Risk assessment defn

Answer 1

the use of a base of scientific research to define the probability of some harm coming to an individual or population as a result of exposure to a substance or situation.

Question 2

risk management

Answer 2

• The public process of deciding what to do where risk has been determined to exist.
• Includes integrating risk assessment with considerations engineering feasibility and figuring out who t exercise our imperative to reduce risk in the light of social, economic, and political factors.

Question 3

What are PCB’s?

Answer 3

• Mixtures of chlorinated compounds.

- Carcinogenic (in high doses) (liver, biliary tract)

Question 4

Components of Health Risk Assessment (Risk Characterization)

Answer 4

1) Hazard Identification –> Dose-Response Assessment

2) Exposure Assessment

Question 5

Epidemiology defn

Answer 5

The study of the distribution and causes of health and illness in human populations

Question 6

Environmental epidemiology Defn

Answer 6

Study of disease and health conditions as linked to environmental factors

Question 7

Toxicology

Answer 7

• Study of harmful actions of chemicals on biologic tissue

- Study of poisons

Question 8

What kind of toxicology testing did Prof. Kanarek engage in? (animals)

Answer 8

• Putting stuff in their hair.
• With dosage kills 1/2 of animals?
• Look for teratogenicity (cause birth defects?)

Question 9

Problems with using Animals to test for Human Stuff

Answer 9

1) Species differences in susceptibility
2) Interactions with other exposures
3) Latent period
4) Low dose problem (requires a larger sample size)

Question 10

What is “measuring risk”?

Answer 10

• Calculating the probability and severity of public harm

- Empirical scientific activity

Question 11

What is “judging safety”

Answer 11

• Judging the safety of risk

- Normative, political, economic, and value laden activity

Question 12

What are the 6 levels of toxicity?

Answer 12

1) Extremely toxic
2) Highly T
3) Moderately T
4) Practically nontoxic
5) Relatively harmless

Question 13

De minimus

Answer 13

• There is an acceptable small amount of each substance.

- There is no such thing as zero risk for any substance.

Question 14

Acceptable lifetime cancer risk

Answer 14

• From EPA and FDA
• One in a million
• 3 cases/year in population of 250 million w/ life expectancy of 74 years

Question 15

How does risk assessment work in practice?

Answer 15

• Given this info:
  1. Scientific knowledge to date on dose-response for a subject
  A) epidemiology
  B) toxicology
  2. Numbers of people potentially exposed
  3. Acceptable risk level (1 in a million)

=> You can calculate how much to allow into environment.

Question 16

Precautionary Principle

Answer 16

“When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.”

Question 17

Four components for public safety

Answer 17

1) Take preventive action in face of uncertainty.
2) Shift burden of proof to proponents of activity.
3) Explore wide range of alternatives to possibly harmful actions.
4) Increase public participation in decision making.