Which of the following is NOT a current and continuing threat to the environmental health of the
US?
-Polluted water affecting both the health of both human and ecosystem.
-Novel coronavirus first identified in China
-International terrorist organizations.
-Air pollution in some areas. correct answers International terrorist organizations
Which of the following components is NOT a part of the "environment" when you investigate the issue of your exposure to arsenic through drinking underground water from domestic wells of
Nevada?
-All residents in Nevada
-Surface water in rivers of Nevada
-Atmospheric emissions of arsenic from Californian mining sites
-Enzymes in your liver responsible for arsenic metabolization correct answers Enzymes in your liver responsible for arsenic metabolization
Which of the following components is NOT part of the IPAT model?
-International
-Population
-Affluence
-Technology correct answers International
Which of the following statements regarding ecosystem is WRONG?
-An ecosystem is a dynamic complex of plant, animal and microorganism communities and nonliving environment as a functional unit.
-The two most important aspect of an ecosystem are trophic structure, and cycles of energy and materials.
-An ecosystem refers to living organisms only, whereas an environment refers to physical setting
in which the organisms live.
-Producers are fed upon by primary consumers that in turn are fed upon by secondary consumers,
and so on. correct answers An ecosystem refers to living organisms only, whereas an environment refers to physical setting in which the organisms live.
Which of the following statements regarding the relationship between humans and the environment is WRONG?
-The progress of human technology can help mitigate pollution
-The development of economics will not always lead to higher pollution
-Human activities can generate and release pollutants throughout the lifecycle of products.
-According to the IPAT model, the environmental quality is always worse in more affluent and more populated countries than in poorer and less populated countries. correct answers According
to the IPAT model, the environmental quality is always worse in more affluent and more populated countries than in poorer and less populated countries.
Which of the following usually does NOT assume thresholds of toxicological effects? -Cancer
-Hepatoxicity
-Neurotoxicity
-Developmental toxicity correct answers Cancer
Which chemical is more toxic: Chemical A with a LD50 value of 5600mg/kg/d vs. Chemical B with a LD50 value of 5.6 mg/kg/d?
-A
-B correct answers B
Which of the following statements regarding "effect dose (EDx)" is CORRECT?
-It represents a dose generating a total risk of x%.
-It represents a dose generating a total risk of x% over background.
-It represents a dose generating an additional risk of x% over background.
-None of above. correct answers It represents a dose generating an additional risk of x% over background.
Assume that feeding rats with dose levels of 0, 3, 6, 12, and 24 mg/kg/day of a chemical causes the death of 3%, 3%, 6%, 10%, and 50% of the rats on average. Identify the no-observed-
adverse-effect-level (NOAEL) in this case.
-0 mg/kg/day
-3 mg/kg/day
-6 mg/kg/day
-12 mg/kg/day
-24 mg/kg/day correct answers 3 mg/kg/day
Assume that feeding rats with dose levels of 0, 3, 6, 12, and 24 mg/kg/day of a chemical causes the death of 3%, 3%, 6%, 10%, and 50% of the rats on average. Identify the lowest-observed-
adverse-effect level (LOAEL) in this case.
-0 mg/kg/day
-3 mg/kg/day
-6 mg/kg/day
-12 mg/kg/day
-24 mg/kg/day correct answers 6 mg/kg/day
Which of the following is NOT usually a common route of exposure to environmental pollutants?
-Intravenous injection.
-Ingestion.
-Inhalation.
-Dermal absorption. correct answers Intravenous injection
Which statement is INCORRECT regarding a Reference Dose (RfD)?
-It aims to protect the entire human population including susceptible subgroups.
-An experimentally determined subchronic or acute NOEAL in an animal toxicological test can be directly used as a reference dose.