Transcript Chapter 15: Environmental Hazards and Human Health

CHAPTER 15: ENVIRONMENTAL
HAZARDS AND HUMAN HEALTH
APES Classical HS 2016`
MAKE A FOOD WEB…..
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Read Acorns are a key food for white-footed
mice, and make a food web of the organisms
discussed…
5 minutes…GO!!!
OF ACORNS, MICE, MOTHS, DEER, TICKS,
SPIROCHETES -AND LYME DISEASE?
 Tick
larvae molt
into nymphs that
overwinter on the
forest floor.
 In the spring
infected nymphs
seek hosts such as
deer and humans.
Ticks do not actually get Lyme
disease from deer,
ticks contract it as larvae when they
feed on infected mice.
Adult female ticks need the deer to
lay their eggs and for food,
LYME DISEASE

Mice carry the bacterium Borrelia burgdorferi
15.1 LINKS BETWEEN HUMAN HEALTH
AND THE ENVIRONMENT
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The picture of health
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Environment: combination of physical,
chemical, and biological factors
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Hazard: anything that can cause injury, death,
disease, damage to personal/public property, or
deterioration or destruction of environmental
component
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Risk: probability of suffering a loss as a result of
exposure to a hazard
Why are we discussing this in an
“environmental science” class???
THE PICTURE OF HEALTH: SOME TERMS
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Health has many dimensions..
Health: state of complete mental, physical and social
well being, and not merely the absence of disease or
infirmity
 …measuring all of these is impossible so we focus on
disease…
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Morbidity: incidence of disease in a population
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Mortality: incidence of death in a population
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Epidemiology: study of presence, distribution, and control
of disease in a population
CAUSES OF HUMAN MORTALITY
ENVIRONMENTAL HAZARDS
Cultural
 Biological
 Physical
 Chemical
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CULTURAL HAZARDS
Consequence of choice
 Risky behavior
 Cultural or lifestyle hazards- result from the
place we live, our socioeconomic status,
occupation, or behavioral choices.
 To what cultural hazards do college students
(sometimes high school students )commonly
subject themselves?
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DEATHS FROM VARIOUS CULTURAL
HAZARDS
BIOLOGICAL HAZARDS
Pathogenic bacteria
 Fungi
 Viruses
 Protozoans
 Worms
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GLOBAL MAP OF TUBERCULOSIS, 2014
INFECTIOUS DISEASES
More prevalent in, but not exclusive to, developing
countries
 Contamination of food and water
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Lack of resources for sanitation
 Lack of education
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Ideal climates for transmission of vector-borne
diseases like malaria
MALARIAL PARASITE LIFE CYCLE
P. 413 FIGURE 15-6
PHYSICAL HAZARDS
Natural disasters, e.g., tornadoes, floods,
hurricanes, and wildfires
 Avoidance of risk important in prevention, e.g.,
building homes in floodplains, and living on the
coast
 Climate change: consequences of elevated
greenhouse gases
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CHEMICAL HAZARDS
Result of industrialization
 Exposure through ingestion, inhalation,
absorption through skin
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May be direct use or accidental
Many chemicals are toxic at low levels
CHEMICAL HAZARDS
74 chemicals are known to be carcinogenic (Table
15-2)
 Environmental carcinogens initiate mutations in
DNA; several mutations lead to a malignancy
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PATHWAYS OF RISK
The risk of being poor
 The cultural risk of tobacco use
 Risk and infectious diseases
 Toxic risk pathways
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THE RISK OF BEING POOR
One major pathway for hazards is poverty
 No money for health insurance
 Higher probability of exposure to environmental
hazards
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THE 10 LEADING GLOBAL RISK FACTORS
Fig. 15-9 here
ENVIRONMENTAL HEALTH
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Factors contributing to the environmental health
of a nation include:
Education
 Nutrition
 Commitment from government
 More equitable distribution of wealth
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THE CULTURAL RISK OF TOBACCO USE
REGULATION OF SMOKING
Warning labels
 Smoke-free zones in public places
 FDA regulations
 Lawsuits against the tobacco industry
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RISK AND INFECTIOUS DISEASES
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One major pathway of risk is contamination of
food and water
Inadequate hygiene
 Inferior sewage treatment
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CONTROL OF INFECTIOUS DISEASE
 Genome
sequencing
of the Anopheles
mosquito
 Bed nets
 Change in land use
practices: wetland
development
 New effective
antimalarial drugs
WORLDWIDE DISTRIBUTION OF MALARIA
TOXIC RISK PATHWAYS
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Categories of impact of airborne pollutants
Chronic: effect takes place over a period of years
 Acute: life-threatening reaction within a period of
hours or days
 Carcinogenic: pollutants initiate cellular change
leading to cancer
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INDOOR AIR POLLUTION: DEVELOPED
COUNTRIES
Hazardous fumes
from home products
 Well-insulated
buildings
 Long exposure to
indoor air
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INDOOR AIR POLLUTION: DEVELOPING
COUNTRIES
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Results from burning biofuels (wood, dung) inside
homes
Acute respiratory infections in children
 Chronic lung diseases
 Lung cancer
 Birth-related problems
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RISK ASSESSMENT
Environmental risk assessment by the EPA
 Public-health risk assessment
 Risk management
 Risk perception
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DEFINITION OF RISK ASSESSMENT
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The process of evaluating the risks associated
with a particular hazard before taking some
action in which the particular hazard is present
LOSS OF LIFE EXPECTANCY FROM VARIOUS
RISKS: TOP FIVE (SEE FIG. 15-16)
Alcoholic
 Poverty
 Smoking – male
 Poor social connections
 Heart disease
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LOSS OF LIFE EXPECTANCY FROM
VARIOUS RISKS
ENVIRONMENTAL RISK ASSESSMENT BY
THE EPA
Hazard assessment (What chemicals cause
cancer?)
 Dose-response assessment (How much?)
 Exposure assessment (How long?)
 Risk characterization (How many will die?)
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PUBLIC-HEALTH RISK ASSESSMENT
Potential global impact
 High likelihood of causality
 Modifiability
 Availability of data
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RISK MANAGEMENT
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Usually involves:
Cost–benefit analysis
 Risk–benefit analysis
 Public preferences
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RISK PERCEPTION: HAZARD VS. OUTRAGE
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Hazard: expresses primarily a concern for fatalities
only
RISK PERCEPTION: HAZARD VS. OUTRAGE
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Outrage includes:
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Lack of familiarity with technology
Extent to which the risk is voluntary
Public impressions of hazards
Overselling safety
Morality
Control
Fairness
RISK ASSESSMENT/MANAGEMENT
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Some suggest we use distributive justice in
making decisions about risk
Ethical process of making certain that everyone
receives proper consideration
 Should reduce environmental racism/injustice
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RISK ASSESSMENT/MANAGEMENT
Not a perfect system
 Precautionary principle
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Lack of certainty should not be used as a reason for
preventing environmental degradation/hazards
The
End