Environmental Law. Nature Reserves of Turkmenistan .ppt

ecology and reserves

1. © 2011 Pearson Education, Inc.
CHAPTER 17
Environmental
Hazards and Human
Health

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An introduction to hazards and human
health
•The highly virulent H5N1 avian flu first appeared in
1997
•Infecting poultry, other birds, and humans
•Hundreds of millions of poultry have been slaughtered
•The 2009 H1N1 swine flu outbreak spread rapidly
•The World Health Organization declared a global
influenza pandemic
•39 new diseases have spread from animals to humans
•SARS, the Ebola virus, West Nile virus, hantavirus
•New diseases will appear as we change the
environment

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Countries with avian flu, 2008

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The old enemies
•The new, emerging diseases are not our greatest
threat
•The common, familiar ones take the greatest toll
•Malaria, diarrhea, respiratory viruses, worms
•Especially in developing countries
•In developed countries, cancer is the killer most
closely linked to the environment
•Due to our exposure to chemicals
•Environmental health: connections between
environmental hazards and human disease and death

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Links between the environment and
health
•Pollution: the presence of a substance in the
environment that because of its composition or
quantity prevents functioning of natural processes and
produces undesirable environmental or health effects
•Pollutant: any material that causes pollution
•Usually by-products of some desirable action
•Agriculture, comfortable homes, transportation, etc.
•Pollution has increased due to population and
consumption
•Along with accumulation of nonbiodegradable products
(e.g., plastic, synthetic organic chemicals)

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Categories of pollution

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Pollution is everywhere
•Any part of the environment can be polluted
•Almost anything can be a pollutant
•The only criterion? The addition of a pollutant results
in undesirable changes
•Impacts can be:
•Aesthetic: hazy air, litter
•On ecosystems: fish or forest die-offs
•On human health: water contaminated with waste
•Local (a contaminated well) or global (ozone depletion)
•Too much of a natural compound (e.g., fertilizer)

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Our existence necessitates waste
production
•We must meet our present needs by managing wastes
•So they don’t jeopardize present or future generations
•Identify the material(s) causing the pollution
•Identify the source(s) of the pollutants
•Clean up the environment
•Prevent pollutants from entering the environment
•Avoid the pollution altogether
•Transitioning to a sustainable society will require a
technology transition from pollution-intensive to
environmentally friendly processes

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Environmental health
•Environment: the whole context of human life
•The physical, chemical, and biological setting of
where and how people live
•Home, air, water, food, workplace, climate, etc.
•Hazard: anything that can cause:
•Injury, disease, death to humans
•Damage to personal or public property
•Deterioration or destruction of environmental parts

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Hazards, risk, and vulnerability
•Undesirable consequences do not necessarily follow
a hazard
•Risk: the probability of suffering injury, disease, death,
or some loss as a result of exposure to a hazard
•Vulnerability: some people (e.g., the poor) are more
vulnerable to certain risks
•Risk = Hazard x Vulnerability
•The presence of avian flu in poultry: a hazard that
presents the risk of humans getting the disease
•People working with poultry are more vulnerable

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The picture of health
•Health: a state of complete physical, social, and
mental well-being
•Not just the absence of disease or infirmity
•Environmental health focuses on disease
•Health: the absence of disease
•Two measures are used to study disease
•Morbidity: the incidence of disease in a population
•Mortality: the incidence of death in a population
•Epidemiology: the study of the presence,
distribution, and prevention of disease in populations

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Public health
•One of the most important activities of government:
protecting the health of its people
•Centers for Disease Control and Prevention (CDC)
•Part of the Department of Health and Human Services
•Provides tools and information to protect health
•Involved in health risk management and prevention
•Each state has its own public-health agency
•Can require shots, quarantines, monitoring diseases,
etc.
•The U.S. has a huge health care industry
•Medicare, Medicaid, hospitals, physicians, etc.

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Other countries
•Most countries have a ministry of health that acts on
behalf of its people to manage and minimize health
risks
•Health policies are limited by information and funding
•Limited funds should go to strategies that achieve the
greatest risk prevention
•Countries have access to the WHO
•Established by the UN in 1948
•Everyone should get the highest possible level of health
•Staffed by professionals and governed by the World
Health Assembly

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Life expectancy
•A universal indicator of health
•In 1955, it was 48 years
•It is now 68 years and will rise to 73 by 2025
•Longer lives: due to social, medical, economic advances
•Epidemiologic transition: decreasing death rates
accompany development
•Infectious diseases are replaced by diseases of aging
•But 92 million children still die each year
•Common diseases kill 47% of people in poor countries
•Industry and intensive agriculture have their own hazards

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Environmental hazards
•Four classes of environmental hazards:
•Cultural, biological, physical, chemical
•There are two ways to consider hazards to health
•Lack of access to resources (clean water, food)
•Exposure to hazards in the environment that brings
risk of injury, disease, or death
•Cultural hazards: many factors that cause death or
disability are a matter of choice
•People engage in risky behavior (smoking, drinking,
drugs, don’t exercise, risky sexual practices, etc.)

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Cultural hazards can kill people
•People derive pleasure or other benefits from
cultural hazards
•They are willing to take the risk they will not be hurt
•Other cultural sources of mortality: living in inner
cities, criminal activity
•Cultural hazards cause 40% of U.S. deaths
•Many causes of death are preventable
•Acquired immune deficiency syndrome (AIDS) is a
sexually transmitted disease
•It is caused mainly by high-risk sexual behavior

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Deaths from cultural hazards in the U.S.

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Biological hazards
•Through history, humans have battled bacteria and
viruses
•The black plague and typhus
•The 19th century brought vaccinations and
bacteriology
•Bacteriologists discovered most bacterial diseases
•The 20th century brought virology, antibiotics,
immunizations
•Global eradication of smallpox; victory over polio
•The battle will never be won
•Diseases are inevitable

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Respiratory diseases
•25% of deaths are due to infectious or parasitic
diseases
•Respiratory infections (diphtheria, influenza, etc.) are
the leading causes of death in this category
•Pneumonia is the most deadly of these diseases
•Respiratory diseases lead to death in developing
nations
•Mostly in children already weakened
•Most children are infected by rotavirus
•They die from untreated diarrhea in developing nations
•Food or water contaminated with bacteria also cause
diarrhea

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Jim Henson

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Tuberculosis, malaria, and parasites
•Mycobacterium tuberculosis infects one-third of all
people
•Tuberculosis has resurged due to complacency, HIV-
weakened immune systems, and drug-resistant
strains
•Malaria kills 881,000 people each year
•A mosquito infects a person with a protozoan parasite
•Red blood cells are destroyed, leading to anemia,
fever, chills, and malaise
•3.5 billion people suffer from parasitic worms
•Hookworms and schistosomes

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Global map of tuberculosis

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Life cycle of malarial parasite

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Physical hazards
•Natural disasters include hurricanes, tornadoes, floods,
fires, earthquakes, landslides, and volcanic eruptions
•The result of hydrological, meteorological, or geological
forces
•Unimaginably dreadful events occurred in 2004-2005
•The Indian Ocean tsunami, Hurricane Katrina,
Pakistan’s earthquake
•Some hazards can’t be anticipated (tornadoes,
earthquakes)
•Others occur because of where people decide to live

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Dangerous physical hazards

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Out of nowhere
•The U.S. has 780 tornadoes/year, more than any
other place
•They are spawned from severe weather
•Winds can reach 300 mph
•They can kill hundreds
•Some natural disasters are unavoidable
•Earthquake-resistant buildings can be constructed
•Tsunami early warnings are increasing
•The poor are the least capable of anticipating and
dealing with disasters

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In harm’s way
•Much loss from natural disasters is due to poor
environmental stewardship
•Deforested hillsides
•Building on floodplains, below volcanoes, on geologic
faults, marshes, and mangrove forests
•People assume disasters happen to other people
•They take risks to live in desirable places
•Stupid zones could be created for areas that
shouldn’t be built
•Areas prone to hurricanes, earthquakes, volcanoes,
etc.

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Chemical hazards
•Industrialization has resulted in technologies that
use chemicals
•Cleaning agents, pesticides, fuels, medicines, paints,
etc.
•Exposure is through ingestion, breathing, the skin,
direct use, or by accident
•Toxicity: condition of being harmful, deadly, or
poisonous
•Depends on exposure and dose (the amount
absorbed)
•Different people have different thresholds of toxicity
•Children and embryos are most sensitive

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Industrial processes and hazards

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Carcinogens
•Many chemicals are hazardous even at very low levels
•Heavy metals, organic solvents, pesticides
•Acute poisoning episodes are understandable and
preventable
•But it is hard to determine effects of long-term exposure
to low levels of substances
•Carcinogens: cancer-causing agents
•Cancer develops over decades, so it is hard to connect
cause with the effect
•There are 51 known and 188 suspected carcinogens
•Developing nations have rising exposure to chemicals

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Carcinogenesis
•Carcinogenesis: the development of a cancer
•It is a process with many steps spread over a long time
•Five or more mutations must occur to initiate a cancer
•Environmental carcinogens bind to, or disrupt, DNA
•This prevents DNA from functioning
•With a mutation, it may take 40 years to lead to a
malignancy
•Cells grow out of control and form tumors
•Which may metastasize (spread)
•The best strategy is prevention

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Pathways of risk
•What pathways lead from risks (of infection),
exposure (to chemicals), and vulnerability (to
hazards) to human deaths?
•A very small number of risk factors cause the vast
majority of premature deaths and disease
•One major pathway for hazards: poverty
•The world’s biggest killer in both developing and
developed nations
•People lack access to health care, clean water,
nutritious food, healthy air, sanitation, and shelter

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The 10 leading global risk factors

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Poor vs. rich nations
•Underweight children: the world’s number one risk factor
•Strongly related to poverty
•Malnutrition kills over 2.2 million children/year
•Wealthy nations have healthier populations
•People protect themselves from hazards
•They die from diseases of old age (cancer, heart disease,
etc.)
•People in developing nations die from infectious diseases
•Developed nations have better-educated people
•They improve their hygiene, immunize children, recognize
dangerous symptoms (e.g., dehydration)

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Public-health clinics

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Priorities
•Education, nutrition, and wealth do not explain
everything
•A nation may make deliberate policy choices to
improve the health of its population
•Instead of militarization or power sources
•Costa Rica, China, and Sri Lanka have longer life
expectancies and lower infant mortality than
expected
•They focused public resources on immunization,
upgrading sewer and water systems, and land reform

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The cultural risk of tobacco use
•Lifestyle choices pose a high risk of accidents and
death
•Not exercising, overeating, fast driving, alcohol, etc.
•Tobacco is the leading cause of death in the U.S.
•Fourth cause of death globally
•Tobacco use is declining in developed countries
•But not in developing countries
•It remains high in former socialist countries of eastern
Europe
•19.8% (43.4 million) of U.S. adults smoke
•Half will die or become disabled

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U.S. deaths caused by smoking

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Marlboro country?
•Tobacco is the only product sold that kills half its
users
•It is clearly correlated with cancer and other lung
diseases
•It is responsible for 29% of U.S. cancer deaths
•5.4 million die worldwide each year
•Synergistic effects: smokers living in polluted air or
working with asbestos have higher rates of lung
cancer
•Black lung disease occurs mainly in smokers
•Smoking costs the U.S. $193 billion/yr in health care
costs and lost job productivity

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Decreasing tobacco use
•Raising taxes: the most effective measure to reduce
tobacco use
•Providing billions of dollars to state and federal
governments
•Other measures to reduce smoking include
warnings, smoke-free workplaces, non-smoking
areas, and banning smoking on domestic flights
•The U.S. smoking population dropped from 42% to
19.8% since warnings began

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Secondhand smoke
•In 1999 the EPA classified environmental tobacco
smoke (ETS), secondhand smoke, as a Class A
(known) carcinogen
•A serious and substantial public health risk
•Specific steps now protect children in public places
•The Occupational Safety and Health Administration
is working to protect workers from ETS
•In 1999, Congress gave the Food and Drug
Administration sweeping power to regulate tobacco
•Overcoming efforts of the powerful tobacco lobby

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Legally speaking
•The attorneys general of several states sued
tobacco companies
•In 1998, 46 states reached a $246 billion settlement
•Tobacco companies would reimburse states for
smoking-related illnesses
•Help finance programs to discourage smoking
•Other lawsuits have not been successful
•Judges ruled that earlier court rulings forbade them
from imposing fines

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FCTC and EMPOWER
•The WHO’s 2003 Framework Convention on Tobacco
Control aims to reduce the spread of smoking
•Bill Gates and New York City’s Mayor Bloomberg
gave the WHO $500 million to combat global smoking
•Monitor tobacco use and prevention policies
•Protect people from tobacco use
•Offer help to those who want to quit
•Warn about dangers of tobacco
•Enforce bans on advertising, promotion, sponsorship
•Raise taxes on tobacco

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Bill Gates and Michael Bloomberg

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Risk and infectious diseases
•Epidemiology is “medical ecology”
•Epidemiologists trace a disease’s location,
transmission, and consequences
•Infectious diseases and parasites are more common
in developing countries
•Inadequate hygiene, inferior sewage treatment
•A lack of resources for public-health infrastructure
•Developed nations also have outbreaks of diseases
•In 1993 Milwaukee’s (Wisconsin) water supply was
contaminated by animal wastes, hospitalizing over
4,000

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Tropical diseases
•The tropics have ideal climates for insect-borne
diseases
•Mosquitoes are vectors for yellow fever, dengue
fever, elephantiasis, Japanese encephalitis, West
Nile, malaria
•Malaria is the most serious
•Control of malaria focuses on vector control: using
pesticides on the Anopheles mosquito
•Or treatment strategies: curing infected people
•Malaria has been eradicated in the U.S.
•DDT is a successful, yet controversial, control for
mosquitoes in developing countries

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Malaria incidence per 1,000 population,
2006

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Net results
•Giving children insecticide-treated nets over their
beds reduces mortality from all causes
•Bed nets, indoor DDT spraying, and effective drugs
reduce malaria deaths
•A cost-effective, large-scale intervention in Africa
•The Plasmodium protozoan is becoming resistant to
drugs
•Chloroquine is now ineffective against malaria
•ACT (artemisinin combination therapy) is effective
• But resistance is appearing

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Insecticide-treated bed net

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Good news
•Molecular biologists have sequenced the genomes
of the Anopheles mosquito and P. falciparum
parasite
•Targeting weak points in both organisms
•Development of new drugs and vaccines will further
reduce malaria
•The Global Malaria Action Plan (GMAP): intends to
eventually eradicate malaria
•Will require billions of dollars
•Will meet the Millennium Development Goal target

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Toxic risk pathways
•Airborne pollutants are hard-to-control hazards
•Hard to measure and avoid
•Three categories of impacts
•Chronic: pollutants cause gradual deterioration of
physiological functioning over years
•Acute: pollutants cause life-threatening reactions
within hours or days
•Carcinogenic: pollutants cause cellular changes
leading to uncontrolled growth and division (cancer)

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Indoor air pollution
•Indoor air pollution can pose an even greater health
risk than outdoor air pollution
•Inside air can contain much higher levels of pollutants
•Indoor air pollution in developed countries is
problematic
•More numbers and types of pollutants are being used
•Insulated buildings trap pollutants inside
•People spend more time indoors than out (e.g.,
children, pregnant women, the elderly or sick)
•There are many sources of indoor air pollution
•The least excusable is from smoking

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Indoor air pollution

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Developing countries
•Developing nations have the most serious threat
•Three billion use wood or dung for cooking and
heating
•Fireplaces, stoves, etc. are not properly ventilated
•Exposing people to carbon monoxide, nitrogen and
sulfur oxides, soot, benzene (a carcinogen)
•Problems associated with indoor cooking: acute
respiratory infections, chronic lung disease (asthma,
bronchitis), lung cancer, birth defects
•Solutions? Ventilated, efficient stoves
•Using bottled gas or liquid fuels instead of biofuels

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Asthma
•One consequence of indoor air pollution
•Asthma is at epidemic proportions in the U.S.
•Affects 20 million each year
•It attacks the respiratory system, causing wheezing,
chest tightness, coughing, shortness of breath
•Acute attacks are sudden and can kill
•Substances that trigger asthma: dust, animals, mold,
secondhand smoke, swimming pool chlorine, gases,
etc.
•Asthma costs $11 billion and kills over 3,800/year in
the U.S.

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Worms, anyone?
•Asthma is more common in developed countries
•Even though developing nations have more indoor air
pollution
•Frequent parasitic worm infections stimulate anti-
inflammation in the immune system
•Protecting people against allergic diseases like
asthma
•Developed nations do not have worms and lack
protection
•Instead of getting worms, identify the molecules that
induce protection and put them in vaccines

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Toxicology
•The link between hazardous substances and health
problems is hard to establish
•A statistical correlation can be established between
exposure and adverse effects
•Toxicology: the science that studies the impacts of
toxic substances on human health
•It investigates the relationships between substances
and environmental or health problems

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Disaster risk
•More than 200 million/year are affected by natural
disasters
•Needing emergency relief efforts, help, and
reconstruction
•Costs $45 billion/year (2000s)
•Much death and misery can be avoided through
disaster risk reduction strategies
•Living with Risk: A Global Review of Disaster
Reduction Initiatives (2004)
•Applies concepts of hazards, risks, and risk
assessment to natural disasters
•Gives policies for guiding and monitoring risk reduction

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The Hyogo Framework for Action (2005)
•168 country delegates met in Kobe, Japan
•The World Conference on Disaster Reduction
•Five priorities for risk reduction
•Make disaster risk reduction a priority
•Know the risks and take action
•Build understanding and awareness: using
knowledge, innovation, and education
•Reduce risks
•Be prepared and ready to act: strengthen disaster
preparedness for effective response

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Risk assessment
•Society still faces hazards and their risks to health
•We need to know about and evaluate these risks
•Diseases in developing countries require responses
out of humanitarian concern
•Treating the sick will continue if prevention is ignored
•Governments get information by evaluating risks
•Risk assessment: the process of evaluating risks
associated with a hazard before taking action in a
situation where the risk is present

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Loss of life expectancy from various
risks

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Risk assessment
•Risk is expressed as the days of lost life expectancy
•Risk can also be expressed as the probability of
dying from a given hazard
•The annual risk of dying from a vehicle accident =
1.6/10,000
•1.6 out of 10,000 who ride in a car will die
•Equal to 300 days of lost life expectancy
•Not many people make choices about hazards
•But risk assessment is important for public policy and
environmental regulation

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Risk assessment by the EPA
•Risk assessment began in the 1970s to understand
the cancer risks of pesticides and other chemicals
•It is now a highly science-based methodology
•National Center for Environmental Assessment
(NCEA)
•The EPA’s lead agency for risk assessment
•Risk assessment for human health has four steps
•Hazard assessment
•Dose-response assessment
•Exposure assessment
•Risk characterization

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Hazard assessment: is this really a
hazard?
•Hazard assessment: the process of examining evidence
•Linking a potential hazard to its harmful effects
•Historical data are often used to calculate risks
•A link may not be clear due to a time delay between
exposure and effect
•An epidemiological study tracks how a sickness spreads
•Are people exposed to a hazard sicker than the
unexposed?
•Animal testing: uses animals to determine what might
happen
•Uses hundreds of animals (mice) over years at high costs

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Animal testing

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Objections to animal testing
•Rodents and humans may have different responses
to a chemical
•Doses given to animals are much higher than
humans are exposed to
•Some people are opposed for ethical reasons
•All chemicals shown to be human carcinogens are
also carcinogenic in test animals

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Just test people?
•Chemical manufacturers used to pay people to test
products
•They are less expensive than animal testing
•A National Academy of Sciences panel stated this was
unjustifiable
•The EPA banned such tests
•The Bush administration pressed to allow testing
•A 2006 EPA ruling allowed testing to restart
•But forbids testing on children or pregnant women
•The Natural Resources Defense Council is suing
•The Obama administration may stop this testing

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Obtaining information on a chemical
•The chemical or process can provide information
•What are its physical or chemical processes?
•How does it induce cancer?
•A weight-of-the-evidence approach: one approach to
determining the carcinogenic potential of a chemical
•Descriptors used in its conclusions include that a
chemical “is likely to be carcinogenic to humans”
•Hazard assessment tells us we may have a problem

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Dose-response and exposure
assessment
•The relationship between the chemical concentrations
(dose) and responses’ incidence and severity is
analyzed
•When a link is shown between exposure and ill effects
•Children are growing and more vulnerable
•Dose-response assessment: a linear response
determines an acceptable level of exposure
•Projections are made about numbers of potential
cancers
•Exposure assessment: exposed groups are identified
•The dose, time, and origin of exposure are determined

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Risk characterization:
what does the science say?
•Risk characterization: pulls all information to determine
risk and its uncertainties
•Science informs the risk manager
•Summaries include data and methods, limitations
•Risk: the probability of a fatal outcome due to the hazard
•The Clean Air Act (1990) directs the EPA to regulate
chemicals with a cancer risk greater than one in a million
•The FDA uses this standard for food, drugs and cosmetics
•A limit: analysts work with available information
•But it’s never enough, which allows some imprecision

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Public-health risk assessment
•Until 2002, most risk assessment was a function of
environmental regulation
•The new effort looks at all risk factors responsible for
poor health and morality
•Of all diseases, how much is caused by this risk?
•Risk factors are chosen for special attention based
on
•Potential global impact: a leading cause of mortality,
etc.
•High likelihood of causality: trace causes and effects
•Modifiability: policies to decrease the factor’s impact
•Availability of data: reliable data must be available

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The DALY
•A common currency is used to assess data
•Allows comparisons between different types of risks
•DALY: disability-adjusted life year
•1 DALY = loss of one healthy year of life
•Assesses a disease in terms of life lost or a disability
•Different countries have different risk factors
•Each risk factor calls for different solutions
•Scientific bases for risk factors are well-understood
•Strategies for cost-effective risk prevention exist
•There is broad agreement about the need for action

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Risk management
•Risk assessment: scientific analysis of hazards and
risks
•Risk management: falls to lawmakers and
administrators
•Involves reviewing information about the hazard
•Deciding whether the evidence justifies regulations
•Public opinion plays a role in both
•Regulatory decisions hinge on
•Cost-benefit analysis: decisions can be very clear
•Risk-benefit analysis: benefits are not expressed in
monetary terms
•Public preferences: some risks are tolerated; some aren’t

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Risk perception
•The U.S. public’s concern about environmental
problems is due to the fear of hazards to life and
health
•Our lives are less hazardous than ever before
•Why do people protest nuclear energy, waste sites,
etc?
•These hazards pose very small risks
•Risk perception: the intuitive judgments about risks
•Perceptions are not consistent with a scientific
analysis of risk

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Hazard versus outrage
•Perception is a matter of outrage, not hazard
•Hazard: a concern for fatalities only
•Outrage: expresses many concerns
•Lack of familiarity with a technology (e.g., nuclear)
•Extent to which a risk is voluntary: people with a choice
accept far greater risks
•Public impression of a hazard: accidents aren’t
forgotten
•Overselling of safety without detailing risks
•Morality: obey a moral imperative, regardless of costs
•Fairness: why accept risk if another benefits?

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Media’s role
•The public’s perception of risk is strongly influenced
by the media
•Outrage is expressed better than hazards
•High outrage quotients: beef from Canada was
prohibited when mad-cow disease was found in two
cows
•But cigarettes kill 443,000/year in the U.S. and
receive little media attention

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Public concern and public policy
•Public concern, not cost-benefit or risk-benefit
analysis, drives public policy
•Congress sets the EPA’s funding priorities
•Which reflects the public’s concern
•Serious risks may get less attention than they deserve
if public outrage is the impetus for public policy
•Environmental risks are seen as less important
•The public has more immediate issues
•Risk communication: important in educating the public
•Done by scientists, educators, government, not media

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Risk communication
•Most effective communication starts with what
people already know
•Finding what they need to know
•Tailoring the message to give people knowledge to
make informed evaluations of risk
•Communication should involve dialogue among
everyone
•Policy makers, experts, the public, other interested
groups
•Public concern must be heard, understood, and
responded to
•It reflects values and concerns that science could omit

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The precautionary principle
•Use of risk assessment has been attacked
•It does not adequately reflect uncertainty
•It is used when a chemical or process is already in use
•The burden of proof of harm falls on the regulators
•The precautionary principle: where an activity threatens
harm to humans or the environment, precautionary
measures should be taken even if some cause-and-
effect relationships are not fully known
•Proponents of the activity, not the public, should bear
the burden of proof

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Using the precautionary principle
•It is well-established in Europe
•It is the basis for environmental laws
•It overlies some U.S. policies
•Pharmaceuticals and pesticides
•A substance is presumed guilty until proven innocent
•It is not permitted until tests prove it is safe
•It can implement stewardship in environmental health
•But should not be a blanket policy
•It can counter pressures from proponents
•Use it where the penalty for being wrong is great

81. © 2011 Pearson Education, Inc.
Stewards of health
•Public-health ministries and agencies are the
primary stewards of a country’s health and welfare
•Public policy should clearly reflect stewardship
principles
•Put the public’s health and environment above the
economic bottom line
•Governments can accomplish much in preventive
health
•But they must nurture scarce resources
•The WHO focuses on reducing risk to promote
health
•Health care providers are also stewards

82. © 2011 Pearson Education, Inc.
CHAPTER 17
Environmental
Hazards and Human
Health
Active Lecture Questions

83. © 2011 Pearson Education, Inc.
True or False: The existence of a hazard means
that undesirable consequences will inevitably
follow.
a.True
b.False
Review Question-1

84. © 2011 Pearson Education, Inc.
True or False: The existence of a hazard means
that undesirable consequences will inevitably
follow.
a.True
b.False
Review Question-1 Answer

85. © 2011 Pearson Education, Inc.
______ is the incidence of disease in a
population, while ______ is the incidence of
death in a population.
a.Mortality; morbidity
b.Morbidity; immortality
c.Morbidity; mortality
d.Immortality; mortality
Review Question-2

86. © 2011 Pearson Education, Inc.
______ is the incidence of disease in a
population, while ______ is the incidence of
death in a population.
a.Mortality; morbidity
b.Morbidity; immortality
c.Morbidity; mortality
d.Immortality; mortality
Review Question-2 Answer

87. © 2011 Pearson Education, Inc.
The infectious disease caused by protozoan
parasites of the genus Plasmodium and
propagated by mosquitoes in tropical areas is
a.tuberculosis.
b.HIV.
c.malaria.
d.rotavirus.
Review Question-3

88. © 2011 Pearson Education, Inc.
The infectious disease caused by protozoan
parasites of the genus Plasmodium and
propagated by mosquitoes in tropical areas is
a.tuberculosis.
b.HIV.
c.malaria.
d.rotavirus.
Review Question-3 Answer

89. © 2011 Pearson Education, Inc.
Which of the following is not a physical hazard?
a.smoking
b.hurricanes
c.tornadoes
d.earthquakes
Review Question-4

90. © 2011 Pearson Education, Inc.
Which of the following is not a physical hazard?
a.smoking
b.hurricanes
c.tornadoes
d.earthquakes
Review Question-4 Answer

91. © 2011 Pearson Education, Inc.
Which of the following is a risk associated with
being poor?
a.being underweight
b.unsafe sex
c.poor sanitation
d.all of the above
Review Question-5

92. © 2011 Pearson Education, Inc.
Which of the following is a risk associated with
being poor?
a.being underweight
b.unsafe sex
c.poor sanitation
d.all of the above
Review Question-5 Answer

93. © 2011 Pearson Education, Inc.
According to Fig. 17-5, the continent most
impacted by tuberculosis is
a.North America.
b.Asia.
c.Australia.
d.Africa.
Interpreting Graphs and Data-1

94. © 2011 Pearson Education, Inc.
According to Fig. 17-5, the continent most
impacted by tuberculosis is
a.North America.
b.Asia.
c.Australia.
d.Africa.
Interpreting Graphs and Data-1 Answer

95. © 2011 Pearson Education, Inc.
According to Fig. 17-6, the number of days of
lost life expectancy due to alcoholism is
approximately
a.1,000.
b.2,000.
c.3,000.
d.4,000.
Interpreting Graphs and Data-2

96. © 2011 Pearson Education, Inc.
According to Fig. 17-6, the number of days of
lost life expectancy due to alcoholism is
approximately
a.1,000.
b.2,000.
c.3,000.
d.4,000.
Interpreting Graphs and Data-2 Answer

97. © 2011 Pearson Education, Inc.
The following is a statement of the ______
principle: “Where an activity raises threats of harm
to human health or the environment, precautionary
measures should be taken even if cause-and-effect
relationships are not fully established scientifically.”
a.causal
b.precautionary
c.measured
d.environmental
Thinking Environmentally-1

98. © 2011 Pearson Education, Inc.
The following is a statement of the ______
principle: “Where an activity raises threats of harm
to human health or the environment, precautionary
measures should be taken even if cause-and-effect
relationships are not fully established scientifically.”
a.causal
b.precautionary
c.measured
d.environmental
Thinking Environmentally-1 Answer

99. © 2011 Pearson Education, Inc.
All of the following are in the top 10 risk factors
for developed countries except
a.tobacco use.
b.high blood pressure.
c.high cholesterol.
d.high fruit and vegetable intake.

Thinking Environmentally-2

100. © 2011 Pearson Education, Inc.
All of the following are in the top 10 risk factors
for developed countries except
a.tobacco use.
b.high blood pressure.
c.high cholesterol.
d.high fruit and vegetable intake.
Thinking Environmentally-2 Answer