- In environmental health, the term toxin refers to a toxic substance that _______________.
|[removed]||is naturally produced by a plant or animal|
|[removed]||occurs in the occupational setting|
|[removed]||results from human activity|
|[removed]||a man-made product introduced into the environment due to human activity|
- In toxicity testing in rodents, the LD50 is a dose that is _______________.
|[removed]||acutely fatal to 50 percent of test animals|
|[removed]||fatal to 50 percent of test animals within a 90-day period|
|[removed]||fatal to 50 percent of test animals after lifetime bioaccumulation|
- Which of the following is not characteristic of a health impact assessment?
|[removed]||It evaluates a site or activity as it is, rather than looking forward in time|
|[removed]||It includes social and economic factors in the assessment|
|[removed]||It incorporates input from community members|
- An exposure pathway connects _______________ to _______________.
|[removed]||an exposure / a change in tissue structure or function|
|[removed]||inhalation / absorption|
|[removed]||the environmental source of a contaminant / the point of exposure|
- The three major routes of human exposure to environmental contaminants are _______________.
|[removed]||by air, water, and soil|
|[removed]||environmental, occupational, and residential|
|[removed]||ingestion, inhalation, and dermal contact|
- The phrase contact with the human envelope is a common definition of _______________.
- The quantity of a toxicant (or its breakdown product) that is available to interact with some vulnerable tissue in the body is called the _______________.
|[removed]||biologically effective dose|
- The body burden of a chemical in the body reflects the net effect of _______________.
|[removed]||absorption and biological effectiveness|
|[removed]||synergism and antagonism|
|[removed]||the processes of toxicokinetics|
- Bioaccumulation is the _______________.
|[removed]||gradual building up of a chemical in the tissue of an organism|
|[removed]||increase of concentrations of a chemical at higher levels of a food pyramid|
|[removed]||movement of a chemical from water to living tissue|
- Which of the following is an example of a biomarker?
|[removed]||Body mass index calculated from measured height and weight|
|[removed]||Concentration of a pesticide in blood|
|[removed]||Inhalation rate in liters per hour|
- The Ames test is a test of a chemical’s _______________.
|[removed]||acute lethality, and is conducted in rodents|
|[removed]||mutagenicity, and is conducted in bacteria|
|[removed]||teratogenic potential, and is conducted mammalian cells|
- Exposure modeling is used to estimate the _______________.
|[removed]||biologically effective dose of a toxicant|
|[removed]||fate and transport of a toxicant|
|[removed]||ingestion of, inhalation of, or dermal contact with a toxicant|
- Conceptually, a reference dose is a dose that has no adverse effects in _______________.
|[removed]||sensitive subpopulations over a long-term exposure|
|[removed]||sensitive subpopulations over a short-term exposure|
|[removed]||the general population over a long-term exposure|
|[removed]||the general population over a short-term exposure|
- Which of the following is one of the major processes which together make up toxicokinetics?
- In doing a risk assessment for a chemical, the usual assumption is that _______________.
|[removed]||carcinogenicity has a threshold; non-cancer effects do not|
|[removed]||non-cancer effects have a threshold; carcinogenicity does not|
|[removed]||both carcinogenicity and non-cancer effects have thresholds|
|[removed]||neither carcinogenicity nor non-cancer effects has a threshold|