Transcript Presentation

MILLER/SPOOLMAN
LIVING IN THE ENVIRONMENT
17TH
Chapter 17
Environmental Hazards and
Human Health
Core Case Study: Are Baby Bottles and Food Cans
Safe To Use? The BPA Controversy
• Some synthetic chemicals act as hormone mimics
and disrupt the human endocrine system
• 93% of Americans older than 6 have BPA levels
above the threshold level set by the EPA
• Higher in children and adolescents
• BPA (bisphenol A)
• Estrogen mimic – excess effects on males
• In polycarbonates and other hardened plastics
• Baby bottles, sipping cups, reusable water bottles,
sports drinks, microwave dishes, food storage
containers. liners of most food and soft drink cans
We Face Many Types of Hazards
1. Biological:
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Pathogen: an organism that causes disease in other
organisms
Chemical
Physical
Cultural
Lifestyle choices
• Risk
• Probability of suffering harm from a hazard
Some Diseases Can Spread from One
Person to Another
• Infectious disease
• Pathogen invades the body and multiplies
• Transmissible disease
• Contagious or communicable disease
• Infectious disease transmitted between people
• Flu, tuberculosis, measles
• Nontransmissible disease
• Not caused by living organisms
• Heart disease, most cancers, diabetes
Some Diseases Can Spread from One
Person to Another
• Infectious diseases spread through
• Air, water, food, body fluids
• Can cause epidemics and pandemics. Can also build
up resistance to drugs and pesticides
• Since 1950, death from infectious diseases have
declined due to
• Better health care, better sanitation, antibiotics,
vaccines
Science: Pathways for Infectious Diseases
in Humans
Fig. 17-3, p. 439
Major Causes of Death from Infectious Diseases
in the World, 2007
Fig. 17-4, p. 439
Case Study: The Growing Global Threat
from Tuberculosis
• One in ten will become sick with TB
• 1.8 million deaths each year, primarily in lessdeveloped countries
• Why is tuberculosis on the rise?
• Not enough screening and control programs
• Genetic resistance to a majority of effective
antibiotics
• Person-to-person contact has increased
• AIDS individuals are very susceptible to TB
Lung Tissue Destroyed by Tuberculosis
Fig. 17-5, p. 440
Viral Diseases and Parasites Kill Large
Numbers of People
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#1 Killer - Influenza or flu virus
#2 Killer - HIV
#3 Killer - Hepatitis B virus (HBV)
Emergent diseases: West Nile virus
• Reduce chances of infection:
1. Wash your hands
2. Avoid touching your face
3. Avoid sick people
We Can Reduce the Incidence of Infectious
Diseases
• Good news
• Vaccinations on the rise
• Oral rehydration therapy
• Bad news
• More money needed for medical research in
developing countries
Some Chemicals Can Cause Cancers,
Mutations, and Birth Defects
• Toxic chemicals
• Carcinogens
• Chemicals, types of radiation, or certain viruses the
cause or promote cancer
• Mutagens
• Chemicals or radiation that cause mutations or increase
their frequency
• Teratogens
• Chemicals that cause harm or birth defects to a fetus or
embryo
Case Study: PCBs Are Everywhere—A
Legacy from the Past
• PCB’s are:
• Class of chlorine-containing compounds
• Very stable
• Nonflammable
• Break down slowly in the environment
• Travel long distances in the air
• Fat soluble
• Biomagnification
• Food chains and webs
• Banned, but found everywhere
Potential Pathways on Which Toxic Chemicals
Move Through the Environment
Fig. 17-9, p. 447
Some Chemicals May Affect Different
Systems
• Some natural and synthetic chemicals in the
environment can weaken and harm our
• Immune system
• Nervous system
• Neurotoxins: PCBs, arsenic, lead, some pesticides
• Endocrine system
Many Factors Determine the Harmful
Health Effects of a Chemical
• Toxicity dependent on
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Dose
Age
Genetic makeup
Multiple chemical sensitivity (MCS)
Solubility
Persistence
Biomagnification
• Response
• Acute effect: immediate or rapid
• Chronic effect: permanent or long-lasting
Toxicity Ratings and Average Lethal Doses
for Humans
Table 17-1, p. 453
Are Trace Levels of Toxic Chemicals
Harmful?
• Insufficient data for most chemicals
• We are all exposed to toxic chemicals
• Are the dangers increasing or are the tests just more
sensitive?
Some Potentially Harmful Chemicals Found in
Most Homes
Fig. 17-15, p. 455
Why Do We Know So Little about the
Harmful Effects of Chemicals?
• Severe limitations estimating toxicity levels and risks
• Only 2% of 100,000 chemicals have been adequately
tested
• 99.5% of chemicals used in the United States are not
supervised by government
Global Outlook: Number of Deaths per
Year in the World from Various Causes
Fig. 17-16, p. 458
MILLER/SPOOLMAN
LIVING IN THE ENVIRONMENT
17TH
Chapter 21
Solid and Hazardous Waste
Core Case Study: E-waste—An Exploding
Problem
• Electronic waste, e-waste: fastest growing solid waste
problem
• Most ends up in landfills and incinerators
• Composition includes
• High-quality plastics, valuable metals, toxic and hazardous
pollutants
• Shipped to other countries - What happens in China and India?
• International Basel Convention
• Bans transferring hazardous wastes from developed countries
to developing countries
Core Case Study: E-waste—An Exploding
Problem
• What should be done?
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Recycle
E-cycle
Reuse
Prevention approach: remove the toxic materials
We Throw Away Huge Amounts of Useful
Things and Hazardous Materials (1)
• Solid waste
• Industrial solid waste
• Mines, farms, industries
• Municipal solid waste (MSW)
• Trash
• Hazardous waste (toxic waste)
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Threatens human health of the environment
Organic compounds
Toxic heavy metals
Radioactive waste
We Throw Away Huge Amounts of Useful
Things and Hazardous Materials (2)
• 80–90% of hazardous wastes produced by developed
countries
• U.S. is the largest producer - Leader in solid waste
problem; Leader in trash production, by weight, per person;
Recycling is helping
• Why reduce solid wastes?
1. ¾ of the materials are an unnecessary waste of the
earth's resources
2. Huge amounts of air pollution, greenhouse gases, and
water pollution
Natural Capital Degradation: Solid Wastes
Polluting a River in Indonesia
Fig. 21-3, p. 560
We Can Cut Solid Wastes by Reducing,
Reusing, and Recycling
• Six strategies:
1. Redesign manufacturing processes and products to
use less material and energy
2. Develop products that are easy to repair, reuse,
remanufacture, compost, or recycle
3. Eliminate or reduce unnecessary packaging
4. Use fee-per-bag waste collection systems
5. Establish cradle-to grave responsibility
6. Restructure urban transportation systems
We Can Burn or Bury Solid Waste or
Produce Less of It
• Waste Management
• Reduce harm, but not amounts
• Waste Reduction
• Use less and focus on reuse, recycle, compost
• Integrated waste management
• Uses a variety of strategies
We Can Use Integrated Management of
Hazardous Waste
• Integrated management of hazardous wastes
• Produce less
• Convert to less hazardous substances
• Rest in long-term safe storage
Case Study: Recycling E-Waste
• 70% goes to China
• Hazardous working conditions
• Includes child workers
• Reduce toxic components in electronics
• Dell and HP take recycle their products
• Europe has high-tech smelters with strict standards
Case Study: Hazardous Waste Regulation in
the United States (1)
• 1976: Resource Conservation and Recovery Act
(RCRA)
• EPA sets standards and gives permits
• Cradle to grave
• Covers only 5% of hazardous wastes
Case Study: Hazardous Waste Regulation in
the United States (2)
• 1980: Comprehensive Environmental,
Compensation, and Liability Act (CERCLA)
• National Priorities List
• 2010: 1300 sites, 340 sites cleaned so far
• Pace of cleanup has slowed
• Superfund is broke
• Laws encouraging the cleanup of brownfields
International Treaties Have Reduced
Hazardous Waste (1)
• Basel Convention
• 1992: in effect
• 1995 amendment: bans all transfers of hazardous
wastes from industrialized countries to lessdeveloped countries
• 2009: Ratified by 195 countries, but not the United
States
International Treaties Have Reduced
Hazardous Waste (2)
• 2000: Delegates from 122 countries completed a
global treaty
• Control 12 persistent organic pollutants (POPs) “Dirty dozen” includes DDT, PCBs, dioxins. Everyone
on earth has POPs in blood
• 2000: Swedish Parliament law
• By 2020 ban all chemicals that are persistent and can
accumulate in living tissue
We Can Make the Transition to
Low-Waste Societies
• 2000: Swedish Parliament law
• By 2020 ban all chemicals that are persistent and can
accumulate in living tissue
• Norway, Austria, and the Netherlands
• Committed to reduce resource waste by 75%
• East Hampton, NY, U.S.
• Reduced solid waste by 85%
Unit 7 test review
• According to 2003 CDC study what % of Americans
over 6 showed trace BPA level above EPA
thresholds?
• What are the 5 main types of hazards?
• Examples of biological hazards, natural hazards, viral
diseases, transmissible and non-transmissible
diseases.
• Terms – pandemic, epidemic, malaria, west nile
virus, lyme disease, carcinogen, immune system,
endocrine system, toxicity, dose, biomagnification,
chronic effects, acute effects.
• The top toxic substances in terms of human and
environmental health.
• % of e-waste components containing materials that
could be recycled/reused?
• US produces how much of the world’s solid waste?
• Approaches for dealing with solid waste (waste
reductions, integrated waste management, etc.)
• % of solid waste buried in US landfills.
• Most efficient beverage container on the market.
• What can people do to save resources?