ENV Exam 3:

The U.S. federal agency tasked with permitting and directing environmental research on pesticides is the A) Department of Agriculture. B) National Parks Service. C) World Health Organization. D) Environmental Protection Agency.

D) Environmental Protection Agency.

Herbicides would be most useful in combating A) mosquitoes that spread malaria in tropical rainforests. B) weeds that infect our agricultural fields. C) bacteria, such as Salmonella, which sometimes contaminate meat. D) fungi that attack plant roots.

B) weeds that infect our agricultural fields.

Most persistent organic pollutants enter food webs at the level of A) primary producers. B) primary consumers. C) secondary consumers. D) decomposers and detritus feeders.

A) primary producers.

Chlorinated hydrocarbon pesticides, like DDT, are synthetic versions of A) heavy metals. B) non-biodegradable, persistent molecules. C) ions and salts. D) vitamins and minerals.

B) non-biodegradable, persistent molecules.

Synergistic effects involving pesticides occur when A) non-persistent pesticides are transformed into persistent pesticides. B) pesticide toxicity interacts with other environmental or chemical factors to produce an unexpected outcome. C) one pesticide is used to control numerous different pests. D) beneficial insects or other wildlife become non-target casualties of pesticides.

B) pesticide toxicity interacts with other environmental or chemical factors to produce an unexpected outcome.

The best way to reduce the pollution of agricultural fertilizer runoff from farm fields is to A) treat the water before it reaches streams or rivers. B) reduce the amount fertilizer leaving the farm fields through such techniques as no-till cultivation. C) add chemicals into the rivers and streams that neutralize the fertilizers. D) raise crops in the rivers and streams that use the fertilizers.

B) reduce the amount fertilizer leaving the farm fields through such techniques as no-till cultivation. (?)

The safe movement of hazardous materials by rail or highway in the United States is regulated by A) individual states and cities. B) the Department of Transportation. C) the regulations of the RCRA. D) the Justice Department.

B) the Department of Transportation.

The cleanup of hazardous waste accumulated in orphan sites is complicated because A) most of the waste is buried below the water table. B) there is no responsible party to clean up the waste. C) the chemicals have evaporated before they could be removed. D) there are no longer places available to dispose of hazardous wastes.

B) there is no responsible party to clean up the waste.

In the processes of pesticide biomagnification and bioaccumulation impacting a food chain A) the pesticide has to be non-biodegradable (persistent) for the processes to occur. B) the greatest levels of mortality are in the producers and first level consumers. C) the concentrations may not be fatal if the top consumers are very small. D) consumers at the top of the food chain will develop rapid pesticide resistance

?

DDT quickly became widely used because it A) was toxic only to specific types of insects. B) gave benefits to agriculture that outweighed its known lethal toxicity to humans. C) was a natural product derived from plants. D) could serve both as a pesticide and a fertilizer.

A ?

The Resource Conservation and Recovery Act and its subsequent amendments generally regulate A) disposal of solid wastes on land. B) the materials that can be recycled. C) the types of materials that can be used in manufactured products. D) the pollutants that can be discharged into the air.

A) disposal of solid wastes on land.

Which of the following is a good example of a biological agent or action that is a hazard to public health? A) Rotavirus infections lead to deadly diarrhea in more than a million children each year. B) Chewing tobacco is known to greatly increase the chances of cancer of the mouth and throat. C) For people living deep in a forest, the drought increased the chances of a deadly forest fire. D) The use of air bags and safety belts has greatly reduced accidental deaths in moving vehicles.

A) Rotavirus infections lead to deadly diarrhea in more than a million children each year.

Why did federal laws limiting pollution of rivers and streams not prevent the pollution and the fires on the Cuyahoga River from 1868 to 1969? A) There were no federal regulations of water pollution at that time. B) This pollution went undetected by agents overwhelmed by the amount of work. C) The federal laws preventing water pollution did not apply to the state where this occurred. D) These industries that polluted the water had been repeatedly fined for polluting and continued to ignore the laws.

A) There were no federal regulations of water pollution at that time.

Which of the following about Bt crops is true? A) They are GM plants that incorporate the gene for producing a potent bacterially produced insecticide. B) They produce chemicals that interfere with the molting of insect pests. C) They should always be planted in pure stands to reduce the chance of Bt resistant pests. D) They produce chemicals that are similar to insect pheromones, interrupting pest mating cycles.

A) They are GM plants that incorporate the gene for producing a potent bacterially produced insecticide.

Determining a discrete threshold level of exposure is most difficult for A) all carcinogens. B) most acids. C) all salts. D) almost all bases.

A) all carcinogens.

Non-persistent pesticides can be more dangerous than persistent pesticides because they usually A) are more toxic. B) last longer in the environment. C) are radioactive. D) are broken down into nontoxic products within a few weeks of application.

A) are more toxic.

Heavy metals can quickly move through ecosystems because they A) are soluble in water as ions and as a few other compounds. B) quickly dissolve in the fats of animals. C) quickly become incorporated into sugars and starch. D) easily clump together and bind tightly to soil compounds.

A) are soluble in water as ions and as a few other compounds.

In a food chain, biomagnification is the result of A) bioaccumulation up to higher trophic levels. B) bioaccumulation down to lower trophic levels. C) higher levels of toxins than in the organisms living in that region. D) rapid elimination of toxic wastes from the body.

A) bioaccumulation up to higher trophic levels.

Our experience with herbicides and insecticides indicates that A) both are capable of selecting for natural resistance by evolution. B) herbicides, but not insecticides, are capable of selecting for natural resistance by evolution. C) insecticides, but not herbicides, are capable of selecting for natural resistance by evolution. D) neither are capable of selecting for natural resistance by evolution.

A) both are capable of selecting for natural resistance by evolution.

Because it does not affect the crop yield or nutritional value, a local grower advertises that in his orchard he does not use A) cosmetic spraying. B) insurance spraying. C) crop rotation. D) natural predators.

A) cosmetic spraying.

The use of pesticides crosses the economic threshold when the cost of A) crop damage is more than the cost of the pesticide. B) pesticide is more than the cost of the crop damage. C) harvesting the crop is more than the cost of raising the crop. D) cost of raising the crop is more than the cost of the crop damage.

A) crop damage is more than the cost of the pesticide.

A farmer extending his farm field bulldozes the banks of a creek, greatly disturbing the creek bed and stirring up clay and humus. The higher levels of clay and humus in the water just downstream will most likely result in A) fewer plants, fewer fish, and cloudy water. B) more plants but fewer fish and cloudy water. C) more plants and more fish but cloudy water. D) more plants and more fish and clearer water.

A) fewer plants, fewer fish, and cloudy water.

Flies are destroying a farmer's crop despite years of investing in pesticides. Investigating an ecological pest control approach, he learn that the female flies that are killing the crop mate only once, lay their eggs, and then die. In fact, he can purchase sterile male flies to release around the crop to keep these flies from reproducing. Such a strategy represents A) genetic control. B) natural enemies control. C) cultural control. D) natural chemical control.

A) genetic control.

POPs such as dioxins and PCB's are transported into arctic ecosystems and food chains by A) global air patterns and then deposited on snow from where they enter streams and plankton. B) being eaten by fish when toxic materials are dumped into oceans. C) local industries run by native people who use toxic chemical processes. D) ocean currents, which contaminate local streams.

A) global air patterns and then deposited on snow from where they enter streams and plankton.

Anaerobic conditions will most likely be generated in a natural water system with A) high levels of DO that is contaminated by pollutants with high BOD values. B) low levels of DO that is contaminated by pollutants with high BOD values. C) high levels of DO that is contaminated by pollutants with low BOD values. D) low levels of DO that is contaminated by pollutants with low BOD values.

A) high levels of DO that is contaminated by pollutants with high BOD values.

The common definition of pest A) is based on the negative impacts of an organism on human activities. B) varies depending upon whether the organism is an herbivore or carnivore. C) varies widely in the world depending upon the particular culture. D) is limited to organisms that are plants.

A) is based on the negative impacts of an organism on human activities.

In a small pond that averages about 6 feet deep, eutrophication typically produces A) low levels of dissolved oxygen and abundant amounts of submerged aquatic vegetation. B) low levels of dissolved oxygen and no submerged aquatic vegetation. C) high levels of dissolved oxygen and abundant amounts of submerged aquatic vegetation. D) high levels of dissolved oxygen and no submerged aquatic vegetation.

A) low levels of dissolved oxygen and abundant amounts of submerged aquatic vegetation.

When exposure to a substance is below the threshold level, we expect to see A) no ill effects. B) acute but no chronic effects. C) chronic but no acute effects. D) short-term but no long-term effects.

A) no ill effects.

The dead zone in the Gulf of Mexico is primarily the result of A) nonpoint sources of pollutants. B) point sources of pollutants. C) a natural cycle related to cold ocean currents. D) industrial pollution by oil refineries in the New Orleans region.

A) nonpoint sources of pollutants.

The EPA's efforts to enforce the Clean Water Act for CAFOs, mountaintop removal mining, and storm water discharges have been opposed by A) political interests supporting the industries affected by regulation. B) fishing organizations. C) supporters of the Endangered Species Act. D) the CDC on the grounds that regulation will increase water-borne diseases.

A) political interests supporting the industries affected by regulation.

The hygiene hypothesis predicts that the lowest levels of asthma should occur in people living in A) poor rural families in developing countries. B) wealthy families in developing countries. C) poor urban families in developed countries. D) wealthy families in developed countries.

A) poor rural families in developing countries.

Entering a new job at a small medical testing facility, Ben is cautioned to handle certain chemicals carefully. Wondering what harm some of these chemicals can potentially cause, Ben asks a coworker. The coworker says, "Well, I think they can cause cancer if you breathe the fumes." Ben wants to be certain. According to OSHA guidelines, Ben should A) read the relevant material safety data sheets. B) search the Internet for medical articles related to these compounds. C) ask the supervisors about the dangers of the substances he handles. D) check the information on the HAZMAT signs in his workplace.

A) read the relevant material safety data sheets.

Many companies have reduced their generation of toxic wastes and saved money by A) recycling toxic materials. B) using different combinations of toxic materials. C) purchasing toxic materials from other companies. D) developing more on-site toxic waste storage facilities.

A) recycling toxic materials.

A woman has a large garden and decides this year she will not let the pests get beyond control. At the earliest sign of insect pests, she applies an organic insecticide and continues to apply it every month throughout the growing season. The next year the woman decides not to use any insecticides, thinking that she must have eliminated the pests with the prior year's treatments. Unfortunately, the pests reappear in numbers greater than she has ever seen before, and her crops are destroyed. Investigating this phenomenon, she learns that she has just experienced a phenomenon known as A) resurgence. B) pesticide resistance. C) natural selection. D) emergence.

A) resurgence.

By design, the molecules that resist biodegradation and include some of the most problematic persistent organic pollutants are the A) synthetic organic compounds. B) inorganic compounds. C) recycled organic compounds. D) chlorinated heavy metals.

A) synthetic organic compounds.

The public's perception of risk is largely shaped by A) the media. B) reading scientific reports on environmental hazards. C) taking environmental science courses in high school or college. D) political affiliation.

A) the media.

Questions about the danger of a particular chemical hazard will relate to that chemical's A) toxicity, exposure, and dose. B) exposure in the natural environment. C) toxicity and abundance in the environment. D) ability to dissolve in either water or oil.

A) toxicity, exposure, and dose.

Despite widespread use of insecticides and herbicides, infestations of insects, plant pathogens, and weeds currently, depending on the type of crop, cause a loss of about A) 0 to 5% of potential agricultural production in the United States. B) 20% to 50% of potential agricultural production in the United States. C) 50% to 80% of potential agricultural production in the United States. D) more than 95% of potential agricultural production in the United States.

B) 20% to 50% of potential agricultural production in the United States.

You study two insect food chains, one with a parasitic wasp laying its eggs in an herbivorous caterpillar and the other with a praying mantis eating an herbivorous meadow grasshopper If a persistent insecticide were applied to the plants in these systems, where would we expect to find the high concentrations due to biomagnification? A) The grasshopper and caterpillar B) The praying mantis and caterpillar C) The caterpillar and parasitic wasp D) The praying mantis and parasitic wasp

B) The praying mantis and caterpillar (?)

The ultimate responsibility for public policy legislation controlling the waters of the United States is the A) EPA. B) U.S. Congress. C) National Oceanic and Atmospheric Administration. D) United States Geological Services.

B) U.S. Congress.

Getting ready to mow the lawn, Jerome spills gasoline on his hands as he tries to fill up the gas tank on the mower. About an hour later, his skin is very red and itches intensely, and he does not feel well. Jerome is experiencing A) chronic effects of a carcinogen. B) acute toxicity from the gasoline. C) metabolic relief from a toxin. D) chronic effects of toxic components of gasoline.

B) acute toxicity from the gasoline.

According to the Environmental Protection Agency, the greatest current water-pollution challenge in the United States is A) sewage-treatment effluent. B) agricultural runoff. C) fluids released from oil wells. D) discharge of substances from factories.

B) agricultural runoff.

Some of the most toxic organic compounds, widely used in plastics, pesticides, and solvents, are the A) heavy metals. B) chlorinated hydrocarbons. C) sulfated hydrocarbons. D) radioactive hydrocarbons.

B) chlorinated hydrocarbons.

Good health in the modern world, with few cases of bacterial infection, is largely the result of A) the development and widespread use of new immunizations. B) clean water supplies and proper treatment of sewage. C) widespread use of bleach, antibiotics, and antibacterial soaps. D) frequent bathing and washing of clothing and dishes.

B) clean water supplies and proper treatment of sewage.

One of the most influential forces encouraging the passage of laws regulating the safety and use of toxic chemicals has been A) international organizations. B) consumer advocacy groups. C) social clubs such as the Rotary and Lions groups. D) international laws.

B) consumer advocacy groups.

Many brownfield sites involve social issues centering around A) the precautionary principle. B) environmental justice. C) ecosystem restoration. D) environmental economics.

B) environmental justice.

The Basel Convention deals with the regulation of A) lawsuits of injured parties against polluting industries. B) international exports of hazardous wastes. C) the cleanup of toxic spills in international waters. D) the use of toxic chemicals in developing nations.

B) international exports of hazardous wastes. (?)

Today, because of its release into the atmosphere by coal and oil-burning power plants, one of the continuing threats to the consumption of large quantities of fish and shellfish around the world is exposure to toxic levels of A) lead. B) mercury. C) sodium. D) copper.

B) mercury.

When college students first learn about the invasion of zebra mussels into the Great Lakes approximately 25 years ago, they frequently ask what controls zebra mussel populations in their native regions. If introducing natural zebra mussel predators into the Great Lakes would not cause new problems, this approach might work as an example of A) cultural control. B) natural enemies control. C) genetic control. D) natural chemical control.

B) natural enemies control.

Which one of the following hazardous-waste disposal methods includes large amounts of evaporation into the air? A) A secure landfill B) A deep-well injection C) An on-site surface impoundment D) A best-demonstrated available technology

C) An on-site surface impoundment

Noticing large amounts of algal growth in her small farm pond, a farmer adds about 20 grass carp to feed on the abundant algae and plants. After several years, the carp grow large, exceeding 20 pounds each in size. Late one summer, the farmer notices that the carp and most of the other fish are dead. The water also smells very bad. Which one of the following is the most likely explanation for the death of these fish? A) The algae overgrew the pond and produced toxic levels of ozone. B) The large carp grew so large that they could not get enough oxygen. C) Bacteria feeding on the large volume of carp feces depleted the oxygen. D) Carbon dioxide released by the carp and algae eventually suffocated the fish in the pond.

C) Bacteria feeding on the large volume of carp feces depleted the oxygen.

An old friend has died from a disease that resulted from his lifelong exposure to a toxic substance. From which of these illnesses did the friend most likely die? A) Whooping cough B) A bacterial infection C) Cancer D) Malaria

C) Cancer

Harmful algal blooms appear to be linked to unusually high levels of nutrient pollution. Which of the following is the most likely source of nutrient pollution in a river drainage system associated with an algal bloom? A) A coal-fired power plant B) A nuclear power plant C) Chicken and hog farms D) A large shopping mall

C) Chicken and hog farms

Which of the following holds the highest levels of oxygen? A) Warm water near the surface of a marsh in Everglades National Park in May B) Warm water in a mud puddle along a dirt road in Nebraska in June C) Cold flowing water in a stream in Ontario in April D) Water at the base of a waterfall that is formed from melting snow in mountains of Oregon in July

C) Cold flowing water in a stream in Ontario in April

Which of the following lists the four sequential steps of risk assessment by the EPA in the correct order? A) Exposure determination, dose-response determination, hazard control, and risk identification B) Risk identification, hazard characterization, dose-response determination, and exposure control C) Hazard assessment, dose-response assessment, exposure assessment, and risk characterization D) Risk characterization, exposure assessment, dose-response assessment, and hazard assessment

C) Hazard assessment, dose-response assessment, exposure assessment, and risk characterization

Which of the following illustrates an anthropogenic form of pollution? A) A large plume of ash from an erupting volcano B) Large clouds of smoke from a forest fire caused by lightning C) Sulfur dioxide released from a coal burning power plant D) Sea salt aerosols in the air above an ocean

C) Sulfur dioxide released from a coal burning power plant

Arriving at the hotel for the meeting, a woman decides to get a workout in the pool. Upon stepping into the pool area, she quickly finds it difficult to breathe because of the high levels of chlorine in the air above the pool. This woman is experiencing A) a lethal reaction to the chlorine in the air. B) a chronic reaction to the chlorine in the air. C) an acute reaction to the chlorine in the air. D) a carcinogenic reaction to the chlorine in the air.

C) an acute reaction to the chlorine in the air.

Chronic pesticide exposure has been clearly linked to A) malaria and bubonic plague. B) viral outbreaks. C) cancer, neurological disorders, and infertility. D) heart disease and strokes.

C) cancer, neurological disorders, and infertility.

Most organisms accumulate synthetic organic chemicals in their bodies because these chemicals A) are easily converted into molecules that are used to build parts of cells. B) are a concentrated source of minerals, needed for cellular metabolism. C) cannot be broken down by the natural metabolic mechanisms. D) are a major source of calories when food is not available.

C) cannot be broken down by the natural metabolic mechanisms.

The people using a river increase their health risks the most if they use the same area of the river for drinking, bathing and A) washing clothes. B) public boat transportation. C) disposal of sewage. D) religious rituals.

C) disposal of sewage. (?)

The federally funded Brownfield Act has been a success by providing cleanup of real or perceived sites of environmental contamination that are not serious enough to reach Superfund status. This has been especially important in the creation of A) waterways for the transportation of coal and oil. B) new national parks in several states. C) economic development in disadvantaged communities. D) new wildlife refuges for outdoor recreation and conservation purposes.

C) economic development in disadvantaged communities.

In much of India, children suffer from stunted growth, which is tied to a syndrome that includes A) lack of food, internal parasites and lack of household fuel. B) animal vectors of viral infection and industrial pollution of water supplies. C) fecal contamination of water supplies, chronic gastric illness, and the inability to absorb nutrients from food. D) lack of dietary fiber and protein and fear generated from constant earthquakes.

C) fecal contamination of water supplies, chronic gastric illness, and the inability to absorb nutrients from food.

Researchers genetically engineer a crop to produce chemicals that attract the natural enemies of a pest. This approach combines A) natural enemies and cultural control. B) cultural and genetic control. C) genetic and natural enemies control. D) cultural control and natural chemical control.

C) genetic and natural enemies control.

A new food preservative has been discovered, and the company that makes it needs to determine if it poses any health risk. Experiments are planned to test the effects of the new preservative on mice. These experiments represent a type of A) respiratory assessment. B) chemical identification. C) hazard assessment. D) risk characterization.

C) hazard assessment.

Risk in environmental health is most related to A) hazards. B) vulnerability. C) hazards multiplied by vulnerability. D) hazards or vulnerability.

C) hazards multiplied by vulnerability.

Submerged aquatic vegetation will most likely thrive when water clarity is A) low and dissolved nutrients are high. B) low and dissolved nutrients are low. C) high and dissolved nutrients are high. D) high and dissolved nutrients are low.

C) high and dissolved nutrients are high.

Concerned about the exposure of children to chlorine, staff running a public pool measure the exact concentration of the chlorine currently in the pool water. However, assuming the amount of water in the pool is unchanging, to accurately determine the dose of chlorine exposure, the staff must also know A) the age of each child in the pool. B) the manufacturer of the chlorine. C) how long each child is in the pool. D) why each child is in the pool.

C) how long each child is in the pool.

Pesticide regulations such as those in FIFRA and FQPA address concerns about the safety of those applying the pesticides, pesticide residues on food, and the effects of pesticides on A) human health. B) the environment. C) human health and the environment. D) human health, the environment, and the local culture.

C) human health and the environment. (?)

Developing countries are said to face double jeopardy for environmental hazards because of the threats of A) physical disasters and traditional cultural practices. B) physical disasters and infectious disease. C) infectious disease and increased exposure to toxic chemicals. D) their dependence on farms for food and income.

C) infectious disease and increased exposure to toxic chemicals.

Being exposed to secondhand smoke by living with a person who smokes A) only poses a health risk for those in the household who smoke. B) has not been shown to increase the health risks of nonsmokers in the home. C) is now known to increase the chances of cancer of everyone in the home. D) increases the risk of cardiovascular disease but not cancer for others living in the home.

C) is now known to increase the chances of cancer of everyone in the home.

A man discovers that he has a fungus attacking the roots of flowers in his garden. If he uses a broad-spectrum fungicide to kill the pests, he may risk A) poisoning his children. B) killing beneficial pollinating insects. C) killing beneficial decomposer fungi and soil mycorrhizae. D) killing many of the flowers he is trying to protect.

C) killing beneficial decomposer fungi and soil mycorrhizae.

As of 2014, the Superfund cleanup program has resulted in A) fewer than 10 sites receiving all the necessary cleanup. B) only about 100 sites receiving all the necessary cleanup. C) more than a thousand sites receiving all the necessary cleanup. D) the necessary cleanup of more than 99% of all Superfund sites.

C) more than a thousand sites receiving all the necessary cleanup.

The air you breathe into your lungs on a daily basis mostly consists of A) oxygen. B) carbon dioxide. C) nitrogen. D) hydrogen.

C) nitrogen.

Because of biomagnification, the most toxic organisms in any ecosystem will be the A) producers. B) primary consumers. C) secondary consumers. D) soils.

C) secondary consumers.

The spread of Integrated Pest Management (IPM) continues because A) traditional methods using pesticides are being outlawed. B) IPM eliminates pests completely and does not create pesticide resistance. C) the benefits of IPM are many and the costs are greatly reduced. D) government regulations worldwide are mandating these techniques.

C) the benefits of IPM are many and the costs are greatly reduced.

Synergistic health risks are associated with a person who smokes and A) delivers mail in a farming community. B) works inside of an office building. C) works in a coal mine. D) jogs in a park for exercise.

C) works in a coal mine.

Which of the following is a good example of a public health hazard related to culture? A) During an earthquake in Japan, people are killed by falling pieces of a building. B) Air pollution near an oil refinery releases known carcinogens into the air. C) People living in southern Africa face the highest risks of developing tuberculosis. D) Eating a high-fat diet and engaging in little exercise, a man becomes obese.

D) Eating a high-fat diet and engaging in little exercise, a man becomes obese.

Of all the sources of pollution, which one releases the greatest amount of toxic substances into the environment? A) Homes B) Automobiles C) Small businesses D) Industrial facilities

D) Industrial facilities

The highest amounts of pesticides or their breakdown products would be found within a cougar in its A) saliva. B) muscles. C) kidneys. D) body fat.

D) body fat.

Today, any pesticide banned for use and sale in the United States A) cannot be produced for use anywhere in the world. B) can be produced but cannot be sold (but can be given away) for use else where in the world. C) cannot be produced but can be sold for use elsewhere in the world. D) can be produced and sold to other countries.

D) can be produced and sold to other countries.

The threshold level for harmful effects of toxic pollutants is most closely related to the A) first appearance of chronic effects. B) time of day of exposure. C) concentration of exposure. D) concentration and duration of exposure.

D) concentration and duration of exposure.

Struggling with various pests attacking the garden every year, a neighbor suggests that next year they might plant a row of marigold flowers completely around the outside edge of the garden. Sure enough, the next year they did this and had fewer pests and better crops. This strategy represents A) genetic control. B) natural enemies control. C) manual control. D) cultural control.

D) cultural control.

Because of the RCRA, disposal facilities for solid wastes on land must A) be sanctioned by permit. B) pretreat toxic wastes to convert them to forms that will not leach. C) track the generation, movement, and disposal of all wastes. D) do all of these activities.

D) do all of these activities.

In general, the release of toxic chemicals into the environment over the past 30 years has A) increased dramatically in the United States, doubling about every 10 years as the U.S. population has increased. B) increased slightly in the United States, about 10% per decade, as the U.S. population has increased. C) remained steady in the world, despite increases in the world's population. D) greatly declined, by more than 60%, despite increases in the world's population.

D) greatly declined, by more than 60%, despite increases in the world's population.

The Centers for Disease Control and Prevention employs many people who study epidemiology. Which of the following best describes the roles of people at the CDC? A) identifying new types of infectious disease. B) the prevention of infectious disease. C) the worldwide distribution of infectious disease. D) identifying, tracking the spread of, and preventing infectious disease.

D) identifying, tracking the spread of, and preventing infectious disease.

Over the past 50 years, global life expectancy has A) decreased by about 5 years primarily due to increases in viral infections. B) stayed about the same due to new diseases spread by global climate change. C) increased by about 5 years due to the development of many poor nations. D) increased by more than 20 years due to better health care and nutrition worldwide.

D) increased by more than 20 years due to better health care and nutrition worldwide.

The local health department is trying to limit the spread of West Nile virus in a suburban community. West Nile Virus is spread by mosquitoes as they feed. In newspapers and on the radio, people in the region are told to drain standing water from any places where mosquitoes might breed. In addition, the health department announces that in a week, they will begin spraying a fog of mosquito poison in the early evening, as soon as the sun sets and mosquitoes become most active. The approach taken by this health department best represents A) chemical treatment. B) agricultural treatment. C) ecological control. D) integrated pest management.

D) integrated pest management.

DDT was widely used and remains in use today in some countries to fight malaria by A) killing the parasite that causes malaria. B) fouling the water used by mosquitoes for reproduction. C) killing the virus that causes malaria. D) killing mosquitoes that are the major malarial vector.

D) killing mosquitoes that are the major malarial vector.

Discharge permits and the Clean Air Act and Clean Water Act A) do not allow any wastes to be dumped into natural waterways. B) limit the type but not the amount of wastes dumped into natural waterways. C) limit the amount but not the type of wastes dumped into natural waterways. D) limit the type and the amount of wastes dumped into natural waterways.

D) limit the type and the amount of wastes dumped into natural waterways.

The water conditions that produce an oligotrophic aquatic community most likely has A) high levels of nutrients and high levels of oxygen. B) low levels of nutrients and low levels of oxygen. C) high levels of nutrients and low levels of oxygen. D) low levels of nutrients and high levels of oxygen.

D) low levels of nutrients and high levels of oxygen.

The WHO World Health Report uses the DALY as a common unit of different types of risks. The DALY is a measurement of the loss of A) one percentage of average life expectancy. B) life per 1,000 people per year. C) one healthy day in a person's life. D) one healthy year in a person's life.

D) one healthy year in a person's life.

Pesticide-resistant insects develop from the widespread use of insecticides because A) pesticides cause mutations in the insects that make them resistant. B) pesticides increase the biotic potential of some insects. C) insects learn to avoid the places where insecticides have been applied. D) over many generations, the naturally resistant pests survive and increase in number.

D) over many generations, the naturally resistant pests survive and increase in number.

About one hundred years ago, cities began to address the problems of sewage disposal by dumping sewage into nearby rivers via storm water drainage systems. One of the results of this strategy was that A) cities no longer needed to treat drinking water that was drawn from nearby river systems. B) the quality of the water in the local rivers and streams greatly improved. C) people living upriver of these cities were more likely to experience contamination of their drinking water sources. D) people living downriver of these cities were more likely to experience contamination of their drinking water sources.

D) people living downriver of these cities were more likely to experience contamination of their drinking water sources.

The evolution of pesticide resistance, resurgence, and secondary-pest outbreaks are only some of the problems that result from reliance on A) crop rotation and biological controls, which disrupt the natural dynamics of ecosystems. B) pesticides, creating the need to alternate between a pesticide and an herbicide every other year. C) rodenticides to kill weeds and insect pests and prevent the spread of viral diseases. D) pesticides, creating a never-ending pesticide treadmill and requiring new pest-fighting strategies.

D) pesticides, creating a never-ending pesticide treadmill and requiring new pest-fighting strategies.

In the United States, where hazardous waste sites and hazardous facilities are located is often dependent upon the A) geological features of the region. B) weather in that particular region. C) proximity to lakes, rivers, and oceans. D) political power of the affected groups.

D) political power of the affected groups.

According to the World Health Organization, the root cause placing people at the highest risk of disease is A) infectious disease. B) cancer. C) heart disease. D) poverty.

D) poverty.

Disproportionate concerns about the safety of public drinking water versus the greater dangers of cigarette smoking reflect problems of A) exposure assessment. B) dose-response assessment. C) hazard assessment. D) public risk perceptions.

D) public risk perceptions.

In using control by natural enemies of pests, from the ecological perspective it is best to A) import enemies from abroad or from distant ecosystems to have the highest kill rate. B) select enemies that have a very broad range of pest prey or hosts. C) couple this method with intensive broad-spectrum pesticide spraying. D) select enemies that are local and have a narrow specificity for the pest in question.

D) select enemies that are local and have a narrow specificity for the pest in question.

The EPA is authorized by the Toxic Substances Control Act (TSCA) to test the safety of chemicals used in bulk in the manufacturing of products. When passed, these regulations required the testing of existing and new chemicals when there are indications of potential risks. Since TSCA was passed, the EPA has A) reversed this guideline, requiring the testing only for substances that are known carcinogens. B) tested and banned more than 300 new and existing substances. C) tested the safety of about half of the 80,000 chemical substances in the inventory. D) tested the safety of less than 1% of the chemical substances in the inventory.

D) tested the safety of less than 1% of the chemical substances in the inventory.

As of 2015, more than 70% of the cost of toxic waste cleanup for most sites has been paid for by A) increasing taxes in the region affected. B) increased sales taxes in the affected state. C) federal dollars in the Superfund. D) the polluters.

D) the polluters.