HWE Exam UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
According to blood analyses performed by the CDC we are exposed to at least.... -
CORRECT ANSWER 145 toxicants
(T/F) The 1993 and 2008 floods are specifically linked to climate change - CORRECT
ANSWER True
Reducing mercury emissions is the responsibility of.... - CORRECT ANSWER A)
Individuals
B) (Power) Industry
C) US Govrnt
D) Industrialized Nations
If at the end of this cohort study, investigators wanted to perform a case-control study on
other exposures, which cohort would controls be recruited from? - CORRECT
ANSWER Both; exposed and non-exposed
(T/F) Associations between exposures and disease in cross-sectional, case-control and cohort
studies prove exposure caused disease. - CORRECT ANSWER False
Types of Services + Examples - CORRECT ANSWER 1. Provisioning Services: food,
drinking water, timber, plants and medicinal benefits
2. Regulating Services: pollination, decomposition, water purification, erosion, carbon
storage and climate regulation
3. Cultural Services: ecosystems, recreation, interactions with nature
4: Supporting Services: photosynthesis, nutrient cycling, creation of soils, water cycle
,A Tragedy of the Commons is a situation "where individuals acting independently and
rationally according to their own self-interest behave contrary to the best interests of the
whole by depleting some common
resource". Discuss one example that could be considered a Tragedy of the Commons (1 extra
point if you provide an example that was not discussed in class): - CORRECT
ANSWER Eastern Island: over user of timber, landscape, few fish, no animals
(T/F) According to the WHO, "Health is the absence of disease or infirmity" - CORRECT
ANSWER False
Examples of natural sources of chemical hazard present in the environment - CORRECT
ANSWER Volcanoes, forest fires, rock, and algae blooms
The English physician Percival Pott is famous for discovering the "association" between an
occupation and a certain diseases. Name the occupation and the
disease. - CORRECT ANSWER 1714-1788; first demonstrated that smoke was linked
to scrotal cancer and sweeps
Name three factors that lead to an increase or decrease in US population - CORRECT
ANSWER Migration, death rates, birth rates
Name the most important routes by which a toxicant can be absorbed by the human body: -
CORRECT ANSWER Skin, GI track, mouth / nose
A visual representation of age and sex composition of a population whereby % of each age
group is represented by a horizontal bar length is called: - CORRECT ANSWER A)
Population triangle
B) ADP Plot (Age Development Picture)
C) Schuster Diagram
*D) Population Pyramid*
, List three ways by which toxicants are eliminated from the body - CORRECT
ANSWER Kidneys, feces, lung, body secretions
(e.g. milk)
What is the LD50 of a chemical? - CORRECT ANSWER The amount of a toxicant per
kg that is enough to kill 50% of a population of animals
**Smaller LD, more toxic**
Explain why the LD50 is adjusted for bodyweight? - CORRECT ANSWER More mass
= higher concentration of LD50 (mg/kg)
Which chemical is more toxic: botulinum toxin or dioxin? - CORRECT
ANSWER Botulinum is a million times more deadly
The content of the gastrointestinal tract is external to the body and a toxicant needs to be
_________________ before it enters the blood stream and causes a harmful effect. -
CORRECT ANSWER Adsorbed
(T/F) The No Observed Adverse Effect Level (NOAEL) serves as basis for
risk assessment calculations. The NOAEL is based on all available scientific
evidence and can be perceived as risk free. - CORRECT ANSWER True
RISK = - CORRECT ANSWER HAZARD x EXPOSURE
Why is it challenging to determine the human carrying capacity of our planet? - CORRECT
ANSWER -Distribution of economy and income levels
-Development of technology
QUESTIONS AND CORRECT ANSWERS
According to blood analyses performed by the CDC we are exposed to at least.... -
CORRECT ANSWER 145 toxicants
(T/F) The 1993 and 2008 floods are specifically linked to climate change - CORRECT
ANSWER True
Reducing mercury emissions is the responsibility of.... - CORRECT ANSWER A)
Individuals
B) (Power) Industry
C) US Govrnt
D) Industrialized Nations
If at the end of this cohort study, investigators wanted to perform a case-control study on
other exposures, which cohort would controls be recruited from? - CORRECT
ANSWER Both; exposed and non-exposed
(T/F) Associations between exposures and disease in cross-sectional, case-control and cohort
studies prove exposure caused disease. - CORRECT ANSWER False
Types of Services + Examples - CORRECT ANSWER 1. Provisioning Services: food,
drinking water, timber, plants and medicinal benefits
2. Regulating Services: pollination, decomposition, water purification, erosion, carbon
storage and climate regulation
3. Cultural Services: ecosystems, recreation, interactions with nature
4: Supporting Services: photosynthesis, nutrient cycling, creation of soils, water cycle
,A Tragedy of the Commons is a situation "where individuals acting independently and
rationally according to their own self-interest behave contrary to the best interests of the
whole by depleting some common
resource". Discuss one example that could be considered a Tragedy of the Commons (1 extra
point if you provide an example that was not discussed in class): - CORRECT
ANSWER Eastern Island: over user of timber, landscape, few fish, no animals
(T/F) According to the WHO, "Health is the absence of disease or infirmity" - CORRECT
ANSWER False
Examples of natural sources of chemical hazard present in the environment - CORRECT
ANSWER Volcanoes, forest fires, rock, and algae blooms
The English physician Percival Pott is famous for discovering the "association" between an
occupation and a certain diseases. Name the occupation and the
disease. - CORRECT ANSWER 1714-1788; first demonstrated that smoke was linked
to scrotal cancer and sweeps
Name three factors that lead to an increase or decrease in US population - CORRECT
ANSWER Migration, death rates, birth rates
Name the most important routes by which a toxicant can be absorbed by the human body: -
CORRECT ANSWER Skin, GI track, mouth / nose
A visual representation of age and sex composition of a population whereby % of each age
group is represented by a horizontal bar length is called: - CORRECT ANSWER A)
Population triangle
B) ADP Plot (Age Development Picture)
C) Schuster Diagram
*D) Population Pyramid*
, List three ways by which toxicants are eliminated from the body - CORRECT
ANSWER Kidneys, feces, lung, body secretions
(e.g. milk)
What is the LD50 of a chemical? - CORRECT ANSWER The amount of a toxicant per
kg that is enough to kill 50% of a population of animals
**Smaller LD, more toxic**
Explain why the LD50 is adjusted for bodyweight? - CORRECT ANSWER More mass
= higher concentration of LD50 (mg/kg)
Which chemical is more toxic: botulinum toxin or dioxin? - CORRECT
ANSWER Botulinum is a million times more deadly
The content of the gastrointestinal tract is external to the body and a toxicant needs to be
_________________ before it enters the blood stream and causes a harmful effect. -
CORRECT ANSWER Adsorbed
(T/F) The No Observed Adverse Effect Level (NOAEL) serves as basis for
risk assessment calculations. The NOAEL is based on all available scientific
evidence and can be perceived as risk free. - CORRECT ANSWER True
RISK = - CORRECT ANSWER HAZARD x EXPOSURE
Why is it challenging to determine the human carrying capacity of our planet? - CORRECT
ANSWER -Distribution of economy and income levels
-Development of technology
