L.6 - Risk

Question 1

Define Risk:

Answer 1

the likelihood of injury, disease or death

Question 2

Define Environmental Risk:

Answer 2

risk resulting from exposure to a potential environmental hazard

Question 3

List some attributes that elevate risk perception:

Answer 3

1) involuntary
2) uncontrollable
3) unknown
4) permanent effect
5) inequitable

Question 4

List some attributes that lower risk perception:

Answer 4

1) voluntary
2) known
3) equitable
4) temporary effect
5) controllable

Question 5

Define Risk Assessment:

Answer 5

the process of estimating the probability of occurrence of an adverse effect on human and ecological health resulting from contaminant exposure

Question 6

What are the three components of risk assessment?

Answer 6

1) Contaminants
2) Receptors
3) Exposure pathways

Question 7

When is a contaminant considered a health concern?

Answer 7

if it’s chemical reaction exceeds acceptable standard

Question 8

List some environmental exposure pathways:

Answer 8

1) air
2) groundwater, surface water
3) soil
4) sediment

Question 9

List some receptors:

Answer 9

1) on-site humans
2) off-site humans
3) ecological: plants, mammals, aquatic organisms

Question 10

Describe the risk assessment process:

Answer 10

1) Hazard assessment
2) Toxicity assessment & exposure assessment
3) Risk characterization+

Question 11

List Toxicant entry ways:

Answer 11

1) ingestion
2) inhalation
3) eye or dermal contact

Question 12

Define acute toxicity:

Answer 12

the ability of a substance to cause biological harm or death soon after a single exposure or dose

Question 12

List Toxicant different fate:

Answer 12

1) eliminated
2) stored

Question 13

Define toxicity:

Answer 13

amount required to kill organisms

Question 14

Define Chronic toxicity:

Answer 14

the development of adverse effects due to long term exposure to a toxicant

Question 15

Define Mutagenesis:

Answer 15

the mechanisms of action of physical, chemical, and biological, agents capable of producing genetic change in living organisms

Question 16

Define Genotoxicity:

Answer 16

a chemical or other agent that damages cellular DNA resulting in mutations or cancer

Question 17

Define Mutations:

Answer 17

permanent change in the DNA sequence that makes up a gene

Question 18

Define Carcinogens:

Answer 18

substance that is capable of causing cancer in humans or animals

Question 19

Define Teratogens:

Answer 19

substance that is capable of interfering with the development of a fetus, causing birth defects

Question 20

Define Somatic cells:

Answer 20

cells that make up the tissues and organs of the body

Question 21

What re germ cells?

Answer 21

sperm, ovum, may transmit to future generations

Question 22

What is meant by non-carcinogenic?

Answer 22

body can recover from, brief or low exposure leaves no effect until next exposure

Question 23

What is meant by carcinogenic?

Answer 23

risk upon exposure (risk never zero), repeated exposures add up

Question 24

Define potency factor:

Answer 24

a toxicity value that quantitatively defines the relationship between dose and response

Question 25

What is potency factor used for?

Answer 25

used in risk assessment to estimate a lifetime probability of an individual developing cancer as a result of exposure to a particular level of potential carcinogen

Question 26

What is uncertainty factor used for (RfD)?

Answer 26

to account for differences in sensitivity between humas (eg. pregnancy, gender, age)

Question 27

Contaminants may undergo:

Answer 27

1) phase changes
2) chemical transformations
3) biological transformations

Question 28

What does the final decision in risk assessment depend on?

Answer 28

1) health risks
2) cost
3) benefits
4) public perception

Question 29

Define Biogeochemistry:

Answer 29

the study of the processes and reactions that govern the composition of the natural environment

Question 29

What does the natural environment encompass?

Answer 29

1) air
2) water
3) earth’s crust
4) soil
5) living organisms

Question 30

What are the trophic levels?

Answer 30

1) producers: manufacture food from inorganic raw materials
2) herbivores: feed on food from producers (primary consumers)
3) carnivores: feed on herbivores (secondary consumers)
4) larger carnivores: feed on other carnivores (higher consumers)

Question 31

Define Biomagnification:

Answer 31

the tendency of some chemicals to become increasingly concentrated at successfully higher trophic levels

Question 32

Define Bioconcentration:

Answer 32

absorption or uptake of a chemical from a source to concentrations in the organisms tissues that are higher that the surrounding environment

Question 33

Define Bioaccumulation:

Answer 33

the degree to which an organism takes up and retains a contaminant