APES
Alec Humphries
Chapter 10 Guided Reading
1: What are some of the chronic health effects of exposure to Benzene?
Drowsiness, headaches, irritation to eyes and skin, loss of consciousness.
2: What are some of the potential sources of Benzene in the environment?
Tobacco smoke, gasoline, industrial sources.
3: Why is it so hard to link health problems to toxic air pollution?
It is not easily measurable.
4: Why it is said that between a state of health and a state of disease is a gray zone of
suboptimal health, a state of imbalance?
You may be unhealthy, but not diagnosed with a disease.
5: Explain what happened at Lake Nyos, Cameroon.
A massive natural release of CO2,, killing 1,800 people.
6: What is the difference between a pollutant and a contaminant?
Contaminant applies directly to chemicals, whereas pollution may be any number of
factors.
7: Define the following:
•Toxin: Substances that are poisonous to living things.
•Toxicology: Study of toxins.
•Carcinogen: Increases cancer.
•Synergism: Interaction of different substances.
•Point sources: Smoke stacks, pipes, stream, etc.
•Area sources (non-point): Urban runoff, mobile sources.
•Mobile sources: Point moving around. Car.
8: Define the following: (Identify when they are used)
•ppm: Small amounts of pollutants/toxins.
•ppb: Same, smaller amounts.
•mg/L: Water pollution
•μg/m3: Air pollutants
9: What is an Infectious Agent? (Give examples):
Viruses, bacteria, etc.
10: Explain what happened to the area surrounding the Sudbury Smelter as a result of the
release of heavy metal pollution into the air.
250 km2 of forest was killed, and remains damaged.
APES
Alec Humphries
Chapter 10 Guided Reading
11: What are some common heavy metals found in the environment? What health hazards
can they pose to humans?
Mercury, lead, cadmium, nickel, gold, platinum, silver, arsenic, etc. These metals can build
up and be stored in tissue, and eventually kill.
12: What is the concept of Body Burden? What are the body burdens for the following?
Quantity of heavy metals in the body.
•Antimony: 8mg
•Mercury: 13mg
•Arsenic: 18mg
•Cadmium: 30mg
•Lead: 150mg
13: Define biomagnification/bioaccumulation:
Accumulation of a substance through the food web.
14: Describe how Cadmium is a good example of biomagnification.
Coal (very low) to ash to plants (low) to herbivores (higher) carnivores (high) people (very
high)
15: How does Mercury enter the environment?
Eruptions, erosion.
16: Define Methylation:
Inorganic mercury is converted to methyl mercury.
17: Define Volatilization:
liquid mercury to vapor.
What are the 4 major factors that must be considered in evaluating and treating toxic
environmental pollutants?
Individuals vary in response, Pollutants may have a threshold, Some effects are reversible,
the effect of a pollutant may be changed naturally.
18: Define: Persistent Organic Pollutant (POP) and describe the properties that define
them.
Synthetic, chlorinated, fat-soluble, toxic, pollutants.
19: Give some examples of HAA’s:
PCBs. DDT, etc.
20: Explain how PCB’s are harmful (found in plastics):
APES
Alec Humphries
Chapter 10 Guided Reading
Impairs neurological behavior.
21: How can Thermal Pollution affect a body of water and it’s biodiversity? Explain.
Heat can kill species inside of a body of water.
22: What are examples of particulates?
Soot and asbestos fibers.
23: Why is asbestos harmful to humans?
Breathing it in causes problems.
24: How can EMF (Electromagnetic Fields) be harmful to humans?
Leukemia, lymphomas, nervous system cancers.
25: How is noise pollution measured?
dB
26: What are some voluntary exposures to pollutants?
Drugs, tobbacco.
27: What is meant by the quote, “everything is poisonous, yet nothing is poisonous”?
Explain.
Everything is poisonous if you ingest enough of it.
28: Describe the “dose-response”.
As the dose increases, the benefit increases, until it hit a maximum. The benefit decreases
until it hits zero, then it is harmful.
29: Define the following:
•LD-50:Lethal dose, 50% of population dies
•ED-50:Effective dose, 50% of population is affected.
•TD-50:Toxic dose, 50% of population is poisoned.
•LD-0: Maximum dose that is nonlethal.
30: Explain the concept of a threshold dose:
Below this dosage, no effect occurs. Above it, effects occur.
31: Define:
•Behavioral tolerance:Results from changes in behavior.
•Physiological tolerance:Results from a physical change.
•Genetic tolerance:Inherited/mutated.
APES
Alec Humphries
Chapter 10 Guided Reading
32: Explain the difference between an acute and chronic effect.
Acute happens quickly, chronic over a period of time.
33: Explain the steps of risk assessment:
Identify the hazard, dose-response assessment, exposure assessment, risk characterization.
34: What is the precautionary principle?
We should still take care of any possible issues before they occur or get out of hand.
36: Why is it difficult to establish standards for acceptable levels of pollution? In giving
your answer, consider physical, climatological, biological, social, and ethical reasons.
"Level of harm" is relative and also a matter of opinion, basically. It changes based on who,
where, when you are and how rich you are.