Chapter 10 Guided Reading
1: What are some of the chronic health effects of exposure to Benzene? Chronic health effects of exposure to Benzene is many types of blood disorders like leukemia.
2: What are some of the potential sources of Benzene in the environment?
Potential sources of Benzene from the environment tobacco smoke and evaporating gasoline at service stations.
3: Why is it so hard to link health problems to toxic air pollution?
Facilities are not breaking federal law and the people have grown near these facilities so they think nothing is causing health problems if they have followed the law.
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?
People may not be diagnosed with a specific disease but may not be healthy.
5: Explain what happened at Lake Nyos, Cameroon. There was pumping gas-rich water to the surface. A warning system was installed in 2001 and one degassing pipe released a little more CO2. Recent data shows that the pipe barely keeps ahead of CO2, therefore it would take the lake 30 to 50 years to make it safe.
6: What is the difference between a pollutant and a contaminant?
Pollutants are unwanted changes in the environment caused by introduction of harmful materials. Contaminants has a similar meeting to pollution and implies making something unfit for a particular use through introduction of undesirable materials.
7: Define the following:
• Toxin: Substances that are poisonous to living things
• Toxicology: Science that studies toxins or suspected toxins.
• Carcinogen: Toxin that increases the risk of cancer
• Synergism: An important subject in considering pollution problems.
• Point sources: Give example: Pollutants commonly introduced in the environment. Smokestacks.
• Area sources (non-point): Give example: Are diffused over the land. Urban runoff.
• Mobile sources: Give example: A type of an area source. Automobile exhaust.
8: Define the following: (Identify when they are used)
• ppm: Parts per million, used when measuring small amounts of pollutants.
• ppb: Parts per billion, used when measuring small amounts of pollutants.
• mg/L: Milligrams per liter for units of concentration for a pollutant.
• μg/m3: Micrograms of pollutant per cubic meter of air, used when measuring air pollutants.
9: What is an Infectious Agent? (Give examples):
An infectious agent is an infectious disease spread by the interaction between individuals and by the food,water,air,soil and animals we come in contact with. An example of an infectious agent was HIV.
A Closer Look 10.1
Sudbury Smelters: A Point Source
10: Explain what happened to the area surrounding the Sudbury Smelter as a result of the release of heavy metal pollution into the air
Nickel contaminated soils up to 50km from the stacks. Forests were devastated by decades of acid rain.
11: What are some common heavy metals found in the environment?
Common heavy metals found in the environment are gold, platinum, silver, bismuth and arsenic.
12: What is the concept of Body Burden? Quantity of heavy metals in our bodies is referred to as body burden
What are the body burdens for the following?
• Antimony: 8mg
• Mercury: 13mg
• Arsenic: 18mg
• Cadmium: 30mg
• Lead: 150mg
13: Define biomagnification/bioaccumulation:
Accumulation or increasing concentration of a substance in living tissue as it moves through a food web.
14: Describe how Cadmium is a good example of biomagnification.
Cadmium has low concentration in ash and soil taken into the plants as they grow, but concentration of cadmium in the plants is 3-5x greater than the concentration in the ash.
15: How does Mercury enter the environment?
Mercury enters the environment from deposition from the atmosphere through precipitation.
16: Define Methylation: When mercury is in surface water, it enters into complex biogeochemical cycles
17: Define Volatilization: Conversion of liquid mercury to vapor form
Read: A Closer Look 10.2- Mercury and Minamata, Japan
What are the 4 major factors that must be considered in evaluating and treating toxic environmental pollutants? Individuals vary in their response to exposure to the same dose or amount of a pollutant; pollutants may have a threshold; some effects are reversible and the chemical form of a pollutant, activity, and its potential to cause health problems may be changed markedly by ecological and biological processes.
18: Define: Persistent Organic Pollutant (POP) and describe the properties that define them
POP's are synthetic compounds that were first produced decades ago. The properties that define a POP is that they have carbon-based molecular structures containing highly reactive chlorine, they are manufactured by people, persistent in the environment, polluting/toxic, soluble in fat and occur in forms that allow them to be transported by wind, water and sediment.
Read: A Closer Look 10.3
How is Dioxin produced?
It is produced as a by-product of chemical reactions including the combustion of compounds containing chlorine in the production of herbicide.
What happened in Times Beach, Missouri?
Times Beach was evacuated after the discovery that oil sprayed on the town's roads to control dust contained dioxin. The entire area of Times Beach had been contaminated.
19: Give some examples of HAA’s:
Herbicides, pesticides, phthalates and PCBs.
20: Explain how PCB’s are harmful (found in plastics):
PCBs interfere with the growth and development of organisms. They also cause many types of human cancers like breast and prostate cancer.
Read: A Closer Look 10.4- Demasculinization and Feminization of Frogs
Explain how hormone disruptors (Endocrine disruptors) work
The hormone disruptors are introduced into the cell. Natural hormones produced by the body send chemical messages to the cells. Natural hormones transmit instructions to the cell DNA. The chemicals bind to the receptor molecules and obstruct the role of natural hormones.
21: How can Thermal Pollution affect a body of water and it’s biodiversity? Explain.
Thermal pollution will cause a body of water become heated up and changes the concentration of dissolved oxygen. This would disrupt fish spawning cycles and the fish might have a higher susceptibility to disease. It also causes physical stress to the fish and make them easier for predators to catch.
22: What are examples of particulates?
Burning of oil and coal, dust storms, fires and volcanic eruptions.
23: Why is asbestos harmful to humans?
Asbestos gives asbestosis, a lung disease. It also causes cancer and tumors.
24: How can EMF (Electromagnetic Fields) be harmful to humans?
People exposed to EMFs have an increased risk of contracting leukemia, lymphomas, and nervous-system cancers.
25: How is noise pollution measured?
Noise pollution is measured in decibels (dB)
26: What are some voluntary exposures to pollutants?
Tobacco, alcohol and other drugs. Use and abuse have lead to a many human ills, including death and chronic disease, criminal activity and straining of human relations.
27: What is meant by the quote, “everything is poisonous, yet nothing is poisonous”? Explain.Too much of a substance can be dangerous and too little of the substance will not harm the person.
28: Describe the “dose-response”. Draw and label the generalized dose-response curve. Explain each step.
The dose response is an effect of a certain chemical on an individual depends on the dose. As the concentration of a substance increases, the more beneficial to life it is. Point A is the point where the concentration is neither beneficial or harmful. Point B is where the high concentration becomes an increasing benefit. The points between B and C is the place of maximum benefit. After this maximum benefit, an increase in concentration will lead to a decreasing benefit. Point D will be just like Point A. After passing point E (more increase in toxins), it will lead to noticeable harm and finally Point F leads to death. The space from point D and F is known to be toxic.
2: What are some of the potential sources of Benzene in the environment?
Potential sources of Benzene from the environment tobacco smoke and evaporating gasoline at service stations.
3: Why is it so hard to link health problems to toxic air pollution?
Facilities are not breaking federal law and the people have grown near these facilities so they think nothing is causing health problems if they have followed the law.
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?
People may not be diagnosed with a specific disease but may not be healthy.
5: Explain what happened at Lake Nyos, Cameroon. There was pumping gas-rich water to the surface. A warning system was installed in 2001 and one degassing pipe released a little more CO2. Recent data shows that the pipe barely keeps ahead of CO2, therefore it would take the lake 30 to 50 years to make it safe.
6: What is the difference between a pollutant and a contaminant?
Pollutants are unwanted changes in the environment caused by introduction of harmful materials. Contaminants has a similar meeting to pollution and implies making something unfit for a particular use through introduction of undesirable materials.
7: Define the following:
• Toxin: Substances that are poisonous to living things
• Toxicology: Science that studies toxins or suspected toxins.
• Carcinogen: Toxin that increases the risk of cancer
• Synergism: An important subject in considering pollution problems.
• Point sources: Give example: Pollutants commonly introduced in the environment. Smokestacks.
• Area sources (non-point): Give example: Are diffused over the land. Urban runoff.
• Mobile sources: Give example: A type of an area source. Automobile exhaust.
8: Define the following: (Identify when they are used)
• ppm: Parts per million, used when measuring small amounts of pollutants.
• ppb: Parts per billion, used when measuring small amounts of pollutants.
• mg/L: Milligrams per liter for units of concentration for a pollutant.
• μg/m3: Micrograms of pollutant per cubic meter of air, used when measuring air pollutants.
9: What is an Infectious Agent? (Give examples):
An infectious agent is an infectious disease spread by the interaction between individuals and by the food,water,air,soil and animals we come in contact with. An example of an infectious agent was HIV.
A Closer Look 10.1
Sudbury Smelters: A Point Source
10: Explain what happened to the area surrounding the Sudbury Smelter as a result of the release of heavy metal pollution into the air
Nickel contaminated soils up to 50km from the stacks. Forests were devastated by decades of acid rain.
11: What are some common heavy metals found in the environment?
Common heavy metals found in the environment are gold, platinum, silver, bismuth and arsenic.
12: What is the concept of Body Burden? Quantity of heavy metals in our bodies is referred to as body burden
What are the body burdens for the following?
• Antimony: 8mg
• Mercury: 13mg
• Arsenic: 18mg
• Cadmium: 30mg
• Lead: 150mg
13: Define biomagnification/bioaccumulation:
Accumulation or increasing concentration of a substance in living tissue as it moves through a food web.
14: Describe how Cadmium is a good example of biomagnification.
Cadmium has low concentration in ash and soil taken into the plants as they grow, but concentration of cadmium in the plants is 3-5x greater than the concentration in the ash.
15: How does Mercury enter the environment?
Mercury enters the environment from deposition from the atmosphere through precipitation.
16: Define Methylation: When mercury is in surface water, it enters into complex biogeochemical cycles
17: Define Volatilization: Conversion of liquid mercury to vapor form
Read: A Closer Look 10.2- Mercury and Minamata, Japan
What are the 4 major factors that must be considered in evaluating and treating toxic environmental pollutants? Individuals vary in their response to exposure to the same dose or amount of a pollutant; pollutants may have a threshold; some effects are reversible and the chemical form of a pollutant, activity, and its potential to cause health problems may be changed markedly by ecological and biological processes.
18: Define: Persistent Organic Pollutant (POP) and describe the properties that define them
POP's are synthetic compounds that were first produced decades ago. The properties that define a POP is that they have carbon-based molecular structures containing highly reactive chlorine, they are manufactured by people, persistent in the environment, polluting/toxic, soluble in fat and occur in forms that allow them to be transported by wind, water and sediment.
Read: A Closer Look 10.3
How is Dioxin produced?
It is produced as a by-product of chemical reactions including the combustion of compounds containing chlorine in the production of herbicide.
What happened in Times Beach, Missouri?
Times Beach was evacuated after the discovery that oil sprayed on the town's roads to control dust contained dioxin. The entire area of Times Beach had been contaminated.
19: Give some examples of HAA’s:
Herbicides, pesticides, phthalates and PCBs.
20: Explain how PCB’s are harmful (found in plastics):
PCBs interfere with the growth and development of organisms. They also cause many types of human cancers like breast and prostate cancer.
Read: A Closer Look 10.4- Demasculinization and Feminization of Frogs
Explain how hormone disruptors (Endocrine disruptors) work
The hormone disruptors are introduced into the cell. Natural hormones produced by the body send chemical messages to the cells. Natural hormones transmit instructions to the cell DNA. The chemicals bind to the receptor molecules and obstruct the role of natural hormones.
21: How can Thermal Pollution affect a body of water and it’s biodiversity? Explain.
Thermal pollution will cause a body of water become heated up and changes the concentration of dissolved oxygen. This would disrupt fish spawning cycles and the fish might have a higher susceptibility to disease. It also causes physical stress to the fish and make them easier for predators to catch.
22: What are examples of particulates?
Burning of oil and coal, dust storms, fires and volcanic eruptions.
23: Why is asbestos harmful to humans?
Asbestos gives asbestosis, a lung disease. It also causes cancer and tumors.
24: How can EMF (Electromagnetic Fields) be harmful to humans?
People exposed to EMFs have an increased risk of contracting leukemia, lymphomas, and nervous-system cancers.
25: How is noise pollution measured?
Noise pollution is measured in decibels (dB)
26: What are some voluntary exposures to pollutants?
Tobacco, alcohol and other drugs. Use and abuse have lead to a many human ills, including death and chronic disease, criminal activity and straining of human relations.
27: What is meant by the quote, “everything is poisonous, yet nothing is poisonous”? Explain.Too much of a substance can be dangerous and too little of the substance will not harm the person.
28: Describe the “dose-response”. Draw and label the generalized dose-response curve. Explain each step.
The dose response is an effect of a certain chemical on an individual depends on the dose. As the concentration of a substance increases, the more beneficial to life it is. Point A is the point where the concentration is neither beneficial or harmful. Point B is where the high concentration becomes an increasing benefit. The points between B and C is the place of maximum benefit. After this maximum benefit, an increase in concentration will lead to a decreasing benefit. Point D will be just like Point A. After passing point E (more increase in toxins), it will lead to noticeable harm and finally Point F leads to death. The space from point D and F is known to be toxic.
29: Define the following:
• LD-50: Crude approximation of a chemical's toxicity.
• ED-50: Dose that causes an effect in 50% of the observed subjects.
• TD-50: Dose that is toxic to 50% of observed subjects.
• LD-0: Maximum dose that doesn't cause any deaths.
30: Explain the concept of a threshold dose: A threshold dose is the maximum dosage before there would be effects on something. Going below the threshold would cause no harm. Going above the threshold would affect the person. Having no threshold would mean that even a little drop could have some negative effect.
31: Define:
• Behavioral tolerance: Results from changes in behavior.
• Physiological tolerance: Results when the body of an individual adjusts to tolerate a higher level of pollutant.
• Genetic tolerance: Or adaptation, results when some individuals in a population are naturally more resistant to a toxin than others.
32: Explain the difference between an acute and chronic effect. Acute effects occurs soon after exposure, usually to large amounts of pollutants. Chronic effects occur over a long period of time usually to small amounts of pollutants.
33: Explain the steps of risk assessment:
- Identifying the hazard- testing materials to see if exposure would cause health problems
- Dose-response assessment- identifying relationships between the dose of a chemical and the health effects on people
- Exposure assessment- evaluates the intensity, duration and frequency of human exposure to a particular chemical pollutant or toxin.
- Risk characterization- Delineate health risk in terms of magnitude of the health problem that might result from exposure to particular pollutant or toxin.
34: What is the precautionary principle?
When there is a threat of serious environmental damage, we should not wait for scientific proof before taking precautionary steps to prevent potential harm to the environment.
Read: “Is Lead in the Urban Environment Contributing to Antisocial Behavior”
35: What is the main point of the discussion about lead in the bones of children and behavior? A concentration of lead in the human system at a young age (where they are more apt to putting things in their mouth, leading them to be more susceptible to lead poisoning) would lead to bones associated with an increased risk of attention-deficit disorder, aggressive behavior and delinquency.
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.
It is difficult to establish standards for acceptable levels of pollution because there is so many types of pollutants. Each of those pollutants have their own acceptable levels that they can have. This would be time consuming to find our the level for all of the pollutants. The scientists would need to find out both the level of pollution that is good and also bad. Not only is it time consuming, but it would also cost money to establish these standards.
• LD-50: Crude approximation of a chemical's toxicity.
• ED-50: Dose that causes an effect in 50% of the observed subjects.
• TD-50: Dose that is toxic to 50% of observed subjects.
• LD-0: Maximum dose that doesn't cause any deaths.
30: Explain the concept of a threshold dose: A threshold dose is the maximum dosage before there would be effects on something. Going below the threshold would cause no harm. Going above the threshold would affect the person. Having no threshold would mean that even a little drop could have some negative effect.
31: Define:
• Behavioral tolerance: Results from changes in behavior.
• Physiological tolerance: Results when the body of an individual adjusts to tolerate a higher level of pollutant.
• Genetic tolerance: Or adaptation, results when some individuals in a population are naturally more resistant to a toxin than others.
32: Explain the difference between an acute and chronic effect. Acute effects occurs soon after exposure, usually to large amounts of pollutants. Chronic effects occur over a long period of time usually to small amounts of pollutants.
33: Explain the steps of risk assessment:
- Identifying the hazard- testing materials to see if exposure would cause health problems
- Dose-response assessment- identifying relationships between the dose of a chemical and the health effects on people
- Exposure assessment- evaluates the intensity, duration and frequency of human exposure to a particular chemical pollutant or toxin.
- Risk characterization- Delineate health risk in terms of magnitude of the health problem that might result from exposure to particular pollutant or toxin.
34: What is the precautionary principle?
When there is a threat of serious environmental damage, we should not wait for scientific proof before taking precautionary steps to prevent potential harm to the environment.
Read: “Is Lead in the Urban Environment Contributing to Antisocial Behavior”
35: What is the main point of the discussion about lead in the bones of children and behavior? A concentration of lead in the human system at a young age (where they are more apt to putting things in their mouth, leading them to be more susceptible to lead poisoning) would lead to bones associated with an increased risk of attention-deficit disorder, aggressive behavior and delinquency.
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.
It is difficult to establish standards for acceptable levels of pollution because there is so many types of pollutants. Each of those pollutants have their own acceptable levels that they can have. This would be time consuming to find our the level for all of the pollutants. The scientists would need to find out both the level of pollution that is good and also bad. Not only is it time consuming, but it would also cost money to establish these standards.