Environmental Hazards and Human Health

1

• Chapter 17
• Environmental Hazards and Human Health

2
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

3
We Face Many Types of Hazards

• Biological
• Pathogen an organism that causes disease in
  other organisms
• Chemical
• Physical
• Cultural
• Lifestyle choices
• Risk
• Probability of suffering harm from a hazard

4
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

5
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

6
Science Pathways for Infectious Diseases in
Humans
Fig. 17-3, p. 439
7
Major Causes of Death from Infectious Diseases in
the World, 2007
Fig. 17-4, p. 439
8
Case Study The Growing Global Threat from
Tuberculosis

• One in ten will become sick with TB
• 1.8 million deaths each year, primarily in
  less-developed 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

9
Lung Tissue Destroyed by Tuberculosis
Fig. 17-5, p. 440
10
Viral Diseases and Parasites Kill Large Numbers
of People

• 1 Killer - Influenza or flu virus
• 2 Killer - HIV
• 3 Killer - Hepatitis B virus (HBV)
• Emergent diseases West Nile virus
• Reduce chances of infection
• Wash your hands
• Avoid touching your face
• Avoid sick people

11
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

12
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

13
Case Study PCBs Are EverywhereA Legacy from the
Past

• PCBs 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

14
Potential Pathways on Which Toxic Chemicals Move
Through the Environment
Fig. 17-9, p. 447
15
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

16
Many Factors Determine the Harmful Health Effects
of a Chemical

• Toxicity dependent on
• Dose
• Age
• Genetic makeup
• Multiple chemical sensitivity (MCS)
• Solubility
• Persistence
• Biomagnification
• Response
• Acute effect immediate or rapid
• Chronic effect permanent or long-lasting

17
Toxicity Ratings and Average Lethal Doses for
Humans
Table 17-1, p. 453
18
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?

19
Some Potentially Harmful Chemicals Found in Most
Homes
Fig. 17-15, p. 455
20
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

21
Global Outlook Number of Deaths per Year in the
World from Various Causes
Fig. 17-16, p. 458
22

• Chapter 21
• Solid and Hazardous Waste

23
Core Case Study E-wasteAn 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

24
Core Case Study E-wasteAn Exploding Problem

• What should be done?
• Recycle
• E-cycle
• Reuse
• Prevention approach remove the toxic materials

25
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)
• Threatens human health of the environment
• Organic compounds
• Toxic heavy metals
• Radioactive waste

26
We Throw Away Huge Amounts of Useful Things and
Hazardous Materials (2)

• 8090 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?
• ¾ of the materials are an unnecessary waste of
  the earth's resources
• Huge amounts of air pollution, greenhouse gases,
  and water pollution

27
Natural Capital Degradation Solid Wastes
Polluting a River in Indonesia
Fig. 21-3, p. 560
28
We Can Cut Solid Wastes by Reducing, Reusing, and
Recycling

• Six strategies
• Redesign manufacturing processes and products to
  use less material and energy
• Develop products that are easy to repair, reuse,
  remanufacture, compost, or recycle
• Eliminate or reduce unnecessary packaging
• Use fee-per-bag waste collection systems
• Establish cradle-to grave responsibility
• Restructure urban transportation systems

29
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

30
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

31
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

32
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

33
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

34
International Treaties Have Reduced Hazardous
Waste (1)

• Basel Convention
• 1992 in effect
• 1995 amendment bans all transfers of hazardous
  wastes from industrialized countries to
  less-developed countries
• 2009 Ratified by 195 countries, but not the
  United States

35
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

36
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

37
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.

38

• 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 worlds 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?