L.6 - Risk Flashcards
Define Risk:
the likelihood of injury, disease or death
Define Environmental Risk:
risk resulting from exposure to a potential environmental hazard
List some attributes that elevate risk perception:
1) involuntary
2) uncontrollable
3) unknown
4) permanent effect
5) inequitable
List some attributes that lower risk perception:
1) voluntary
2) known
3) equitable
4) temporary effect
5) controllable
Define Risk Assessment:
the process of estimating the probability of occurrence of an adverse effect on human and ecological health resulting from contaminant exposure
What are the three components of risk assessment?
1) Contaminants
2) Receptors
3) Exposure pathways
When is a contaminant considered a health concern?
if it’s chemical reaction exceeds acceptable standard
List some environmental exposure pathways:
1) air
2) groundwater, surface water
3) soil
4) sediment
List some receptors:
1) on-site humans
2) off-site humans
3) ecological: plants, mammals, aquatic organisms
Describe the risk assessment process:
1) Hazard assessment
2) Toxicity assessment & exposure assessment
3) Risk characterization+
List Toxicant entry ways:
1) ingestion
2) inhalation
3) eye or dermal contact
Define acute toxicity:
the ability of a substance to cause biological harm or death soon after a single exposure or dose
List Toxicant different fate:
1) eliminated
2) stored
Define toxicity:
amount required to kill organisms
Define Chronic toxicity:
the development of adverse effects due to long term exposure to a toxicant
Define Mutagenesis:
the mechanisms of action of physical, chemical, and biological, agents capable of producing genetic change in living organisms
Define Genotoxicity:
a chemical or other agent that damages cellular DNA resulting in mutations or cancer
Define Mutations:
permanent change in the DNA sequence that makes up a gene
Define Carcinogens:
substance that is capable of causing cancer in humans or animals
Define Teratogens:
substance that is capable of interfering with the development of a fetus, causing birth defects
Define Somatic cells:
cells that make up the tissues and organs of the body
What re germ cells?
sperm, ovum, may transmit to future generations
What is meant by non-carcinogenic?
body can recover from, brief or low exposure leaves no effect until next exposure
What is meant by carcinogenic?
risk upon exposure (risk never zero), repeated exposures add up
Define potency factor:
a toxicity value that quantitatively defines the relationship between dose and response
What is potency factor used for?
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
What is uncertainty factor used for (RfD)?
to account for differences in sensitivity between humas (eg. pregnancy, gender, age)
Contaminants may undergo:
1) phase changes
2) chemical transformations
3) biological transformations
What does the final decision in risk assessment depend on?
1) health risks
2) cost
3) benefits
4) public perception
Define Biogeochemistry:
the study of the processes and reactions that govern the composition of the natural environment
What does the natural environment encompass?
1) air
2) water
3) earth’s crust
4) soil
5) living organisms
What are the trophic levels?
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)
Define Biomagnification:
the tendency of some chemicals to become increasingly concentrated at successfully higher trophic levels
Define Bioconcentration:
absorption or uptake of a chemical from a source to concentrations in the organisms tissues that are higher that the surrounding environment
Define Bioaccumulation:
the degree to which an organism takes up and retains a contaminant
