APES Unit 4: Human Population and Environmental Hazards

How has the global TFR changed since 1955?

Global TFR dropped from 5 to 2.4

% change equation

% Change = ((new - original) / original) x 100

Annual % growth rate equation

% Growth Rate = (((births + immigrants) - (deaths + emigrants)) / total population) x 100

Natural rate of increase/decrease equation

(crude birth rate - crude death rate) / 10

zoning

Designating parcels of land for particular types of use.

Doubling Time (rule of 70) equation

70 / % Growth Rate

cultural carrying capacity

The limit on population growth that would allow most people in an area or the world to live in reasonable comfort and freedom without impairing the ability of the planet to sustain future generations.

Figure 22-8 Undesirable Impacts of Urban Sprawl

Some of the undesirable impacts of urban sprawl, or car-dependent development: land and biodiversity, water, energy and air and climate, and economic effects.

What are the world's three most populous countries?

1. China 2. India 3. USA

Describe Tuberculosis

An extremely contagious bacterial infection of the lungs.

List three major trends in global urban growth.

1. The percentage of the global population living in urban areas has increased sharply, and this trend is projected to continue. 2. The numbers and sizes of urban areas are mushrooming. 3. Poverty is becoming increasingly urbanized, mostly in less-developed countries.

Describe the three phases of urban growth in the United States.

1. people migrated from rural areas to large central cities. 2. many people migrated from large central cities to smaller cities and suburbs. 3. many people migrated from the North and East to the South and West.

urbanization

Creation or growth of urban areas, or cities, and their surrounding developed land.

infectious disease

Disease caused when a pathogen such as a bacterium, virus, or parasite invades the body and multiplies in its cells and tissues. Examples are flu, HIV, malaria, tuberculosis, and measles.

What are environmental refugees and how quickly are their numbers growing?

Environmental refugees—people who had to leave their homes because of water or food shortages, soil erosion, or some other form of environmental degradation or depletion In 2012, the UN projected that by 2020, there will be 50 million environmental refugees.

demographic transition

Hypothesis that countries, as they become industrialized, have declines in death rates followed by declines in birth rates.

population change

Increase or decrease in the size of a population. It is equal to (Births + Immigration) − (Deaths + Emigration).

pathogen

Living organism that can cause disease in another organism. Examples include bacteria, viruses, and parasites.

Figure 22-18 Mass Transit Rail Trade-offs

Mass-transit rail systems in urban areas have advantages and disadvantages. Advantages: uses less energy and produces less air pollution than cars do, uses less land than roads and parking lots use, cause fewer injuries and deaths than cars. Disadvantages: expensive to build and maintain, cost-effective only in densely populated areas, commits riders to transportation schedules.

What is a neurotoxin and why is methylmercury an especially dangerous one?

Neurotoxins are natural and synthetic chemicals in the environment. Methylmercury is an especially dangerous neurotoxin because it is so persistent in the environment and it can be biologically magnified in food chains and food webs.

infant mortality rate

Number of babies out of every 1,000 born each year who die before their first birthday.

Describe the potential for urban indoor farming.

One method that city dwellers could implement quickly is the use of rooftop greenhouses to provide them with most of their fruits and vegetables. Researchers have found that such greenhouses use as little as 10% of the water and 5% of the area occupied by conventional farms to produce similar yields. These scientists estimate that such a farm could provide vegetables, fruits, chickens, eggs, and fish (grown in aquaculture tanks) for up to 50,000 people. Hydroponic crops would be grown on the upper floors. Chickens (and the eggs they produce) and fish that feed on plant wastes would be grown on lower floors. Thus, an urban vertical farm would mimic nature by applying all three scientific principles of sustainability.

Describe the eco-city model and how it applies the principles of sustainability.

Such cities are people-oriented, not car-oriented, and their residents are able to walk, bike, or use low-polluting mass transit for most of their travel. Much of their energy comes from solar cells on the rooftops and walls of buildings, solar hot-water heaters on rooftops, and micro-wind turbines, as well as from geothermal heating and cooling systems. They work to ensure that the buildings, vehicles, and appliances they use meet high energy-efficiency standards. They typically reuse, recycle, and compost 60-80% of their municipal solid waste. Eco-city residents apply the biodiversity principle by preserving or planting trees and plants that are adapted to their local climate and soils. They work to clean up and restore all abandoned lots and industrial sites and to preserve forests, grasslands, wetlands, and farms on the city's outskirts. They often make use of green roofs to reduce energy use and help cool city buildings. And in the ideal eco-city, parks are plentiful and easily available to everyone. Finally, much of the food that eco-city dwellers eat comes from urban or regional organic farms, solar greenhouses, community gardens, and small gardens on rooftops, in yards, and in window boxes. In the future, large-scale rooftop greenhouses and vertical high-rise urban farms might contribute to urban food supplies.

Figure 17-3 Pathways of Infectious Disease

There are a number of pathways by which infectious disease organisms can enter the human body, such as pets, livestock, wild animals, insects, food, and water.

What are the major disadvantages of urbanization?

- Intense population pressure and high population densities make most of the world's cities more environmentally unsustainable every year. - Lack vegetation - Lots of water problems - Have huge ecological footprints - Concentrate pollution and health problems - Have excessive noise - Affect local climates and cause light pollution

What are the major advantages and disadvantages of motor vehicles?

- Motor vehicles provide mobility and offer a convenient and comfortable way to get from one place to another. For many people, they are symbols of power, sex appeal, social status, and success. Also, much of the world's economy is built on producing motor vehicles and supplying fuel, roads, services, and repairs for them. - Globally, automobile accidents kill about 1.3 million people a year—an average of nearly 3,600 deaths per day—and injure another 50 million people. They also kill about 50 million wild animals and family pets every year. Motor vehicles are the world's largest source of outdoor air pollution. Motor vehicles have helped to create urban sprawl and the car commuter culture. Another problem is congestion.

What are the five key goals of new urbanism?

- Walkable and bike-friendly neighborhoods - Mixed-use and diversity - Quality urban design - Environmental sustainability - Smart transportation

What are six indicators that scientists study to assess a community's level of sustainability?

- energy bills - water-use rates - recycling rates - composting rates - local food production - green space and other common areas

List four ways to reduce dependence on motor vehicles.

- fund programs to educate people about the hidden costs they are paying for gasoline. - use gasoline tax revenues to help finance mass-transit systems, bike lanes, and sidewalks as alternatives to cars, and to reduce taxes on income, wages, and wealth to offset the increased taxes on gasoline. - raise parking fees and charge tolls on roads, tunnels, and bridges leading into cities—especially during peak traffic times. - car-sharing networks that provide short-term rental of cars.

List nine factors that can affect the birth rates and fertility rates.

- importance of children as a part of the labor force - cost of raising and educating children - availability of, or lack of, private and public pension systems - infant deaths - urbanization - educational and employment opportunities available for women - average age at marriage - availability of legal abortions and reliable birth control methods - religious beliefs, traditions, and cultural norms

List five factors that have contributed to genetic resistance in bacteria to commonly used antibiotics.

- the spread of bacteria around the globe by human travel and international trade - overuse of pesticides - overuse of antibiotics for colds, flu, and sore throats, most of which are viral diseases that cannot be treated with antibiotics - widely used to control disease and to promote growth in dairy and beef cattle, poultry, hogs, and other livestock - growing use of antibacterial hand soaps and other antibacterial cleansers is probably promoting antibiotic resistance in bacteria

What are three factors that affect the level of harm caused by a chemical?

1. Dose 2. Solubility 3. Persistence

What are three ways to preserve open spaces around a city?

1. Draw a boundary around the city and to prohibit urban development outside that boundary (Urban Growth Boundary) 2. Surround a large city with a greenbelt—an open area reserved for recreation, sustainable forestry, or other nondestructive uses 3. Create municipal parks

Figure 17-19 Home Toxins

A number of potentially harmful chemicals are found in many homes: Shampoo (Perfluorochemicals to add shine), Nail Polish (Perfluorochemicals and phthalates), Perfume (phthalates), Hairspray (Phthalates), Food (Some food contains BPA), Milk (Fat contains dioxins and flame retardants), Frying Pan (Nonstick coating contains perfluorochemicals), Tile Floor (Contains perfluorochemicals, phthalates, and pesticides), Fruit (Imported fruit may contain pesticides banned in the U.S.), Water Bottle (Can contain BPA), Computer (Flame retardant coatings of plastic casing and wiring), Toys (Vinyl toys contain phthalates), Tennis Shoes (Can contain phthalates), Sofa (Foam padding contains flame retardants and perfluorochemicals), TV (Wiring and plastic casing contain flame retardants), Carpet (Padding and carpet fibers contain flame retardants, perfluorochemicals, and pesticides), Mattress (Flame retardants in stuffing), Baby Bottle (Can contain BPA), Clothing (Can contain perfluorochemicals), and Teddy Bear (Some stuffed animals made overseas contain flame retardants and/or pesticides).

dose

Amount of a potentially harmful substance an individual ingests, inhales, or absorbs through the skin.

response

Amount of health damage caused by exposure to a certain dose of a harmful substance or form of radiation.

Figure 22-15 Transportation Priorities

An up-side down pyramid shows the hierarchy of transportation priorities in more-sustainable cities. The top holds pedestrians, then there are bicycles, then public transportation, then commercial vehicles, then multiple occupancy vehicles, and finally at the bottom is single occupancy vehicles.

crude death rate

Annual number of deaths per 1,000 people in the population of a geographic area at the midpoint of a given year.

crude birth rate

Annual number of live births per 1,000 people in the population of a geographic area at the midpoint of a given year.

noise pollution

Any unwanted, disturbing, or harmful sound that impairs or interferes with hearing, causes stress, hampers concentration and work efficiency, or causes accidents.

Explain how the reduction of poverty and empowerment of women can help countries to slow their population growth.

As countries become industrialized and economically developed, their populations tend to grow more slowly. Most of the world's less-developed countries will make a demographic transition over the next few decades, mostly because newer technologies will help them to develop economically and to raise their per capita incomes. A number of studies show that women tend to have fewer children if they are educated, have the ability to control their own fertility, earn an income of their own, and live in societies that do not suppress their rights. Poor women who cannot read often have an average of five to seven children, compared to two or fewer children in societies where almost all women can read.

replacement-level fertility

Average number of children a couple must bear to replace themselves. The average for a country or the world usually is slightly higher than two children per couple (2.1 in the United States and 2.5 in some developing countries) mostly because some children die before reaching their reproductive years.

life expectancy

Average number of years a newborn infant can be expected to live.

Distinguish among bacteria, viruses, and parasites, and give examples of diseases that each can cause.

Bacteria are singe-cell organisms that are found everywhere and that can multiply very rapidly on their own. Viruses smaller than bacteria and work by invading a cell and taking over its genetic machinery to copy themselves and then spreading throughout a body. Parasites are organisms that live on or inside other organisms and feed on them. An example of a disease caused by bacteria is strep throat. An example of a disease caused by a virus is the flu. An example of a disease caused by a parasite is malaria.

Figure 22-16 Bicycle Trade-offs

Bicycle use has advantages and disadvantages. Advantages: Are quite and nonpolluting, Take few resources to manufacture, Burn no fossil fuels, and Require little parking space. Disadvantages: Provide little protection in an accident, Provide no protection from bad weather, Are impractical for long trips, and Bike lanes and secure bike storage not yet widespread.

Figure 22-17 Buses Trade-offs

Bus rapid-transit systems and conventional bus systems in urban areas have advantages and disadvantages. Advantages: reduce car use and air pollution, can be rerouted as needed, cheaper than heavy-rail system. Disadvantages: can lose money because the require affordable fares, can get caught in traffic and add to noise and pollution, commit riders to transportation schedules.

Summarize concerns over exposure to phthalates.

Caused birth defects and liver cancer, kidney and liver damage, premature breast development, immune system suppression, and abnormal sexual development. Sharp drops in male sperm counts and sperm motility; rising rates of testicular cancer and genital birth defects in men; and rising rates of breast cancer in women. Some scientists believe that as a precaution during this period of research, we should sharply reduce our use of potentially harmful hormone disrupters, especially in products frequently used by pregnant women, infants, young children, and teenagers.

Describe Malaria

Caused by a parasite that is spread by the bites of certain mosquito species. It infects and destroys red blood cells, causing intense fever, chills, drenching sweats, severe abdominal pain, vomiting, headaches, and increased susceptibility to other diseases.

mutagens

Chemical or form of radiation that causes inheritable changes (mutations) in the DNA molecules in genes.

teratogens

Chemical, ionizing agent, or virus that causes birth defects.

carcinogens

Chemicals, ionizing radiation, and viruses that cause or promote the development of cancer.

Figure 6-14 Problems with Rapid Population Decline

Countries currently faced with rapidly declining populations include Japan, Russia, Germany, Bulgaria, Hungary, Ukraine, Serbia, Greece, Portugal, and Italy. Rapid population decline can cause several problems: can threaten economic growth, labor shortages, less government revenues with fewer workers, less entrepreneurship and new business formation, less likelihood for new technology development, increasing public deficits to fund higher pension and health-care costs, and pensions may be cut and retirement age increased.

transmissible disease

Disease that is caused by living organisms (such as bacteria, viruses, and parasitic worms) and can spread from one person to another by air, water, food, or body fluids (or in some cases by insects or other organisms).

nontransmissible disease

Disease that is not caused by living organisms and does not spread from one person to another. Examples include most cancers, diabetes, cardiovascular disease, and malnutrition.

Distinguish between an epidemic and a pandemic of an infectious disease.

Epidemic is a large-scale outbreak of an infectious disease in an area or a country, while a pandemic is global.

total fertility rate (TFR)

Estimate of the average number of children who will be born alive to a woman during her lifetime if she passes through all her childbearing years (ages 15-44) conforming to age-specific fertility rates of a given year. More simply, it is an estimate of the average number of children that women in a given population will have during their childbearing years.

Summarize India's efforts to control its population growth.

For decades, the Indian government has provided family planning services throughout the country and has strongly promoted a smaller average family size. Even so, Indian women have an average of 2.5 children.

smart growth

Form of urban planning that recognizes that urban growth will occur but uses zoning laws and other tools to prevent sprawl, direct growth to certain areas, protect ecologically sensitive and important lands and waterways, and develop urban areas that are more environmentally sustainable and more enjoyable places to live.

Summarize China's efforts to control its population growth.

Government officials decided to take measures that eventually led to the establishment of the world's most extensive, intrusive, and strict family planning and birth control program. . The government provides contraceptives, sterilizations, and abortions for married couples. In addition, married couples pledging to have no more than one child receive a number of benefits, including better housing, more food, free health care, salary bonuses, and preferential job opportunities for their child. Couples who break their pledge lose such benefits.

cluster development

Group housing (town homes, apartments, condos) and leave 30-50% open space.

urban sprawl

Growth of low-density development on the edges of cities and towns.

What are hormonally active agents (HAAs), what risks do they pose, and how can we reduce these risks?

Hormonally active agents are molecules of certain pesticides and other synthetic chemicals. They disrupt the endocrine systems in humans and in some other animals. Reduce risks: Eat certified organic produce and meats, Avoid processed, prepackaged, and canned foods, Use glass and ceramic cookware, Store food and drinks in glass containers, Use only natural cleaning and personal care products, Use natural fabric shower curtains, not vinyl, Avoid artificial air fresheners, fabric softeners, and dryer sheets, Use only glass baby bottles and BPA-free, phthalate-free sipping cups, pacifiers, and toys.

risk analysis

Identifying hazards, evaluating the nature and severity of risks associated with the hazards (risk assessment), ranking risks (comparative risk analysis), using this and other information to determine options and make decisions about reducing or eliminating risks (risk management), and communicating information about risks to decision makers and the public (risk communication).

Why there are more boys than girls in some countries?

In China, where families are strongly encouraged to have only one child, there is a strong preference for male children, partly because daughters are likely to marry and leave their parents. Some pregnant Chinese women use ultrasound to determine the gender of their fetuses and get an abortion if the child is female.

emergent disease

Infections that have recently appeared within a population or those whose incidence or geographic range is rapidly increasing or threatens to increase in the near future.

toxicity

Measure of the harmfulness of a substance.

migration

Movement of people into and out of specific geographic areas.

fertility rate

Number of children born to an average woman in a population during her lifetime.

Describe HIV/AIDS

On a global scale, according to the WHO, HIV infects about 2.5 million people every year, and the complications resulting from AIDS kill about 1.7 million people annually.

Give an example of a risk from each of the following: - Biological hazards - Chemical hazards - Physical hazards - Cultural hazards - Lifestyle choices

- Biological Hazards: pathogens, including bacteria, viruses, parasites, protozoa, and fungi. - Chemical Hazards: harmful chemicals in our air, water, soil, food, and human-made products. - Physical Hazards: fire, earthquakes, volcanic eruptions, floods, and storms. - Cultural Hazards: unsafe working conditions, unsafe highways, criminal assault, and poverty. - Lifestyle Choices: smoking, making poor food choices, drinking too much alcohol, and having unsafe sex.

What are the major advantages of urbanization?

- Cities are centers of economic development, innovation, education, technological advances, social and cultural diversity, and jobs. - Urban residents in many parts of the world tend to live longer than do rural residents and to have lower infant mortality and fertility rates. - They also have better access to medical care, family planning, education, and social services than do their rural counterparts. - Recycling is more economically feasible because of the high concentrations of recyclable materials in urban areas. - Concentrating people in cities can help to preserve biodiversity by reducing the stress on wildlife habitats. - Multistory apartment and office buildings in central cities require less energy per person to heat and cool them than do single-family homes and smaller office buildings in suburbs. - Also, central-city dwellers tend to drive less and rely more on mass transportation, walking, and bicycling.

What are five factors that can cause people to misjudge risks?

- Fear - Degree of control - Whether a risk is catastrophic - Optimism bias - Instant gratification

Summarize the three major population growth trends recognized by demographers.

- In recent decades, the rate of population growth has slowed, but the world's population is still growing at a rate of about 1.2%. - Demographers recognize that, geographically, human population growth is unevenly distributed and this pattern is expected to continue. - The movement of people from rural areas to cities. More than half of the world's people now live in urban areas, or cities and their surrounding suburbs.

Summarize the debate over whether and how long the human population can keep growing.

One view is that we have exceeded some of those limits, with too many people collectively degrading the earth's life-support system. To some scientists and other analysts, the key problem is overpopulation because of the sheer number of people in less-developed countries, which have 82% of the world's population. To others, the key factor is overconsumption in affluent, more-developed countries because of their high rates of resource use per person. Another view of population growth is that, so far, technological advances have allowed us to overcome the environmental limits that all populations of other species face and that this has had the effect of increasing the earth's carrying capacity for our species. They point out that average life expectancy in most of the world has been steadily rising despite dire warnings from some environmental scientists that we are seriously degrading our life-support system. Some of these analysts argue that because of our technological ingenuity, there are few, if any, limits to human population growth and resource use per person. They believe that we can continue ever-increasing economic growth and avoid serious damage to our life-support systems by making technological advances in areas such as food production and medicine, and by finding substitutes for resources that we are depleting. As a result, they see no need to slow the world's population growth. Proponents of slowing and eventually stopping population growth point out that we are not providing the basic necessities for about 1.4 billion people. Proponents of slowing growth also warn of two potentially serious consequences that we could face if we do not sharply lower birth rates. First, death rates might increase because of declining health and environmental conditions and increasing social disruption in some areas. Second, resource use and degradation of normally renewable resources may intensify as more consumers increase their already large ecological footprints in more-developed countries and in rapidly developing countries. No one knows how close we are to environmental limits that, many scientists say, eventually will control the size of the human population. However, these scientists argue that human population growth is a vital scientific, political, economic, and ethical issue that we must confront.

What are PCBs and why are they a threat?

PCBs are a class of more than 200 chlorine-containing organic compounds that are very stable and nonflammable. They exist as oily liquids or solids but, under certain conditions, they can enter the air as a vapor. Research showed that they could cause liver cancer and other cancers in test animals. Studies also showed that pregnant women exposed to PCBs gave birth to underweight babies who eventually suffered permanent neurological damage, sharply lower-than-average IQs, and long-term growth problems.

age structure

Percentage of the population (or number of people of each sex) at each age level in a population.

land-use planning

Planning to determine the best present and future uses of each parcel of land.

dose response curve

Plot of data showing the effects of various doses of a toxic agent on a group of test organisms.

Population change equation

Population Change = (Births + Immigrants) − (Deaths + Emigration)

risk

Probability that something undesirable will result from deliberate or accidental exposure to a hazard.

risk assessment

Process of gathering data and making assumptions to estimate short- and long-term harmful effects on human health or the environment from exposure to hazards associated with the use of a particular product or technology.

family planning

Providing information, clinical services, and contraceptives to help people choose the number and spacing of children they want to have.

What factors could hinder some less-developed countries from making this transition?

Rapid population growth, extreme poverty, and increasing environmental degradation and resource depletion in some low-income, less-developed countries could leave these countries stuck in stage 2 of the demographic transition. Since 1985, economic assistance from more-developed countries has generally dropped. The resulting shortage of funds, coupled with poor economies in some countries, could leave large numbers of people trapped in poverty, which could in turn keep population growth rates high in such countries.

Figure 22-20 Rapid Rail Trade-offs

Rapid-rail systems between urban areas have advantages and disadvantages. Advantages: much more energy efficient per rider than cars and planes are, produces less air pollution than cars and planes, can reduce need for air travel, cars, roads, and parking areas. Disadvantages: costly to run and maintain, causes noise and vibration for nearby residents, adds some risk of collision at car crossings.

urban growth

Rate of growth of an urban population.

Explain why the use of the precautionary principle and pollution prevention to deal with health threats from chemicals is controversial.

Requires two major changes in the way we evaluate risks. First, we would assume that new chemicals and technologies could be harmful until scientific studies could show otherwise. Second, we would remove existing chemicals and technologies that appear to have a strong chance of causing significant harm from the market until we could establish their safety. Manufacturers and businesses contend that widespread application of the much more precautionary REACH approach would make it too expensive and almost impossible to introduce any new chemical or technology. Proponents of increased reliance on using pollution prevention agree that we can go too far, but argue that we have an ethical responsibility to reduce known or potentially serious risks to human health, to the earth's life-support system, and to future generations, in keeping with one of the social science principles of sustainability. Proponents also point out that using the precautionary principle focuses the efforts and creativity of scientists, engineers, and businesses on finding solutions to pollution problems based on prevention rather than on cleanup. It also reduces health risks for employees and society, frees businesses from having to deal with pollution regulations, and reduces the threat of lawsuits from injured parties. In some cases, applying this principle helps companies to increase their profits from sales of safer products and innovative technologies, and it improves the public image of businesses operating in this manner. Experience shows that such pollution control often is only a temporary solution that can be overwhelmed by a growing population consuming more goods and services and producing more pollution. Environmental and health scientists say we can do better than this by putting much greater emphasis on pollution prevention.

What are some of the reasons why people live in cities?

Rural people are pulled to urban areas in search of jobs, food, housing, educational opportunities, better health care, and entertainment. Some are also pushed from rural to urban areas by factors such as poverty lack of land for growing food, famine, war, and religious, racial, and political conflicts.

Figure 17-20 Greatest Threats to Human Health

Scientists have estimated the number of deaths per year in the world from various causes. Numbers in parentheses represent these death tolls in terms of numbers of fully loaded 200-passenger jet airplanes crashing every day of the year with no survivors. Poverty/Malnutrition/Disease Cycle causes an annual death tool of 11 million. Tobacco causes an annual death toll of 6 million. Pneumonia and Flu cause an annual death toll of 3.2 million. Air Pollution causes an annual death toll of 3.2 million. HIV/AIDS causes an annual death toll of 1.7 million. Diarrhea causes a annual death toll of 1.6 million. Tuberculosis causes an annual death rate of 1.4 million. Automobile Accidents causes an annual death toll of 1.2 million. Work-related Injury and Disease causes an annual death toll of 1.1 million. Hepatitis B causes an annual death toll of 1 million. Malaria causes an annual death toll of 655,000. Measles causes an annual death toll of 139,000.

birth rate

See crude birth rate.

death rate

See crude death rate

toxic chemical

See poison, carcinogen, hazardous chemical, mutagen, teratogen.

toxicology

Study of the adverse effects of chemicals on health.

Figure 17-4 Deadliest Infectious Diseases

The World Health Organization has estimated that the world's seven deadliest infectious diseases killed about 10 million people per year—most of them poor people in less-developed countries. This averages about 27,400 mostly preventable deaths every day. Pneumonia and flu (bacteria and viruses) 3.2 million. HIV/AIDS (virus) 1.7 million. Diarrheal diseases (bacteria and viruses) 1.6 million. Tuberculosis (bacteria) 1.4 million. Hepatitis B (virus) 1 million. Malaria (protozoa) 655,000. Measles (virus) 139,000.

Summarize concerns about exposure to bisphenol A (BPA) and the controversy over what to do about exposure to this chemical.

The effects of BPA include brain damage, early puberty, decreased sperm quality, certain cancers, heart disease, obesity, liver damage, impaired immune function, type 2 diabetes, hyperactivity, impaired learning, impotence in males, and obesity. Exposure to BPA in the womb can cause behavior and emotional problems in young girls, including hyperactivity, aggressive behavior, anxiety, and depression. BPA can be a possible contributor to breast cancer in women. In 2011, the German Society of Toxicology concluded that BPA in polycarbonate plastic containers and in the linings of food and beverage cans "represents no noteworthy risk to the health of the human population," arguing that not enough studies showing adverse effects had been reproduced to confirm the results. It would be difficult to replace the plastic resins containing BPA or BPS that line food containers (Figure 17-C) and that help to prevent food contamination and spoilage.

Figure 17-12 Mercury Pollution

There are a number of ways to prevent or control inputs of mercury into the environment from human sources—mostly coal-burning power plants and incinerators. Prevention: phase out waste incineration, remove mercury from coal before it is burned, switch from coal to natural gas and renewable energy resources. Control: sharply reduce mercury emissions from coal-burning plants and incinerators, label all products containing mercury, collect and recycle batteries and other products containing mercury.

Figure 17-9 Ways to Reduce Infectious Disease

There are a number of ways to prevent or reduce the incidence of infectious diseases, especially in less-developed countries. Increase research on tropical diseases and vaccines, reduce poverty and malnutrition, improve drinking water quality, reduce unnecessary use of antibiotics, sharply reduce use of antibiotics on livestock, immunize children against major viral diseases, provide oral rehydration for diarrhea victims, and conduct global campaign to reduce HIV/AIDS.

Figure 17-21 Effects of Poverty

These are some of the harmful effects that result from living in poverty: Lack of access to adequate sanitation facilities effects 2.6 billion people (37% of world's population). Lack of access to enough fuel for heating and cooking effects 2 billion people (28% of world's population). Lack of access to electricity effects 2 billion people (28% of world's population). Lack of access to adequate health care effects 1.1 billion people (15% of world's population). Lack of access to adequate housing effects 1 billion people (14% of world's population). Lack of access to enough food for good health effects 925 million people (13% of world's population). Lack of access to clean drinking water effects 880 million people (12% of world's population).

Describe Influenza

Transmitted by the body fluids or airborne emissions of an infected person. Easily transmitted and especially potent flu viruses could spread around the world n a pandemic that could kill millions of people in only a few months.

Describe West Nile virus

Transmitted to humans by the bite of a common mosquito that gets infected when it feeds on birds that carry the virus.

risk management

Use of risk assessment and other information to determine options and make decisions about reducing or eliminating risks.

Figure 6-4 Altering Nature to Meet Our Needs

We humans have altered the natural systems that sustain our lives and economies in at least eight major ways to meet the increasing needs and wants of our growing population. Reducing biodiversity, Increasing use of net primary productivity, Increasing genetic resistance in pest species and disease- causing bacteria, Eliminating many natural predators, Introducing harmful species into natural communities, Using some renewable resources faster than they can be replenished, Disrupting natural chemical cycling and energy flow, and Relying mostly on polluting and climate-changing fossil fuels.

Figure 17-15 Reduce Exposure to Endocrine Disruptors

You can reduce your exposure, and that of any children you care for, to hormone disrupters. Eat certified organic produce and meats. Avoid processed, prepackaged, and canned foods. Use glass and ceramic cookware. Store food and drinks in glass container. Use only natural cleaning and personal care products. Use natural fabric shower curtains, not vinyl. Avoid artificial air fresheners, fabric softeners, and dryer sheets. Use only glass baby bottles and BPA-free, phthalate-free sipping cups, pacifiers, and toys.