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Happy Earth Day ?

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Title: Happy Earth Day ?


1
Happy Earth Day ?
2
First Earth Day
  • Senator Gaylord Nelson (Wisconsin)
  • Building on idea of anti-war rallies, decided to
    hold teach-in about environment
  • April 22, 1970 estimated 20 million people (10
    US population) participated

3
Toxic Substances
  • ES118 Spring 2008

4
Love Canal
  • Hooker Chemical Co. dumped tons of toxic waste
    (PCBs, dioxin, benzene, lindane) in Niagara
    Falls, NY
  • 1953 Hooker sold site to Niagara Falls School
    Board for 1 and deed that absolved them of
    liability
  • 1978 State disclosed site could be harmful
  • 1,000 families affected, higher miscarriage rate,
    many more birth defects
  • Lois Gibbs formed homeowners association,
    national attention

5
Love Canal--Impact
  • 1978 President Carter declared LC federal
    disaster area, cleanup began
  • Occidental Petroleum (bought Hooker) ultimately
    paid over 200 million to state, federal
    government and residents
  • Led to major federal legislation that gave EPA
    authority to control hazardous waste

6
Aftermath of Love Canal
  • 1980 Comprehensive Response, Compensation, and
    Liability Act (CRCLA), commonly known as
    Superfund
  • Goal Identify hazardous waste sites and clean up
    sites on a priority basis
  • Worst sites put on National Priorities List (NPL)
    and scheduled for cleanup
  • Make responsible parties pay for cleanup when
    possible
  • Initially 1.6 billion fund to identify and clean
    up worst sites, tax on manufacturers of certain
    organic chemicals and oil importers
  • 1986 Superfund Amendments and Reauthorization Act
    (SARA) right to know policy
  • Emergency Planning and Community Right-to-Know
    Act provided for public release of information
    about chemicals made by, stored in, and released
    by businesses through Toxics Release Inventory
    (TRI)
  • What happened?
  • gt44,000 sites evaluated, by 2004 about 1,200
    active NPL sites, and about 900 cleaned up and/or
    removed
  • gt27 billion spent
  • Depletion of trust fund under Bush Administration
    in 2003, relies now on annual appropriations of
    tax dollars and money recovered from companies
    linked to sites

7
Overview
  • Milestones and extent of problem
  • Factors that affect toxicity and classes of toxic
    substances
  • How do we monitor impact of toxic substances?
  • How do we regulate toxic substances?

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
8
Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
9
(No Transcript)
10
The chemical revolution
  • The number and amount of chemicals substances
    sold commercially in the US has grown dramatically

11
How widespread a problem?
  • 35,000 chemicals used daily in US industry
  • 500-1,000 new chemicals created annually
  • 120,000 US establishments create and distribute
    chemicals
  • lt7 proposed for manufacture EPA reviewed
  • gt 20,700 pesticides used in US, and gt1.2 billion
    lbs of pesticides produced annually, with gt890
    active ingredients
  • EPA has prohibited or restricted manufacture of
    more than 500 commercial chemicals, including
    DDT, dioxin, asbestos, PCBs

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
12
Are toxic substances unique?
  • Many are valuable for agricultural, industrial,
    or consumer products
  • We often dont have a good idea of the degree of
    risk of these chemicals
  • Probability of injury may be small for any one
    individual, but since even low levels of exposure
    can be harmful, often a problem for many

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
13
Toxicity response
  • Type and amount of health damage
  • Acute toxicity Immediate or rapid reaction
  • Subtle (e.g., cough or headache from urban air
    pollution)
  • Violent (e.g., convulsions induced from exposure
    to certain pesticides)
  • Chronic toxicity Permanent or long-lasting
    consequence
  • Examples Mesothelioma, rare form of cancer from
    exposure to asbestos

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
14
What factors affect toxicity?
  • Dose Amount of a substance a person has
    ingested, inhaled, or absorbed through the skin
  • Frequency and duration of exposure
  • Biological reactivity of the chemical in question
  • Age and health of person exposed
  • Routs of exposure
  • Inhalation (e.g., smoking, sitting in
    traffic)--rapid
  • Ingestion (e.g., food, liquids)
  • Dermal exposure (e.g., spilled on skin)typically
    slow
  • How well a person can detoxify a substance
  • Genetic makeup of a person
  • Synergistic responses Response can be greater
    than sum of individual chemicals

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
15
Classes of toxic substances
  • Much of our concern about toxic chemicals stem
    from the long-term increased risk from
  • Mutagens
  • Carcinogens
  • Teratogens
  • Immune and nervous system
  • Endocrine system

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
16
Mutagens
Classes of toxic substances ? Mutagens Carcinogens
Teratogens Immune nervous systems Endocrine
system
  • Substances that can cause mutations in DNA.
    Examples include
  • Chemicals (e.g., Benzene)
  • Radiation (e.g., UV, high-energy radiation)

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
17
Carcinogens
Classes of toxic substances Mutagens ?
Carcinogens Teratogens Immune nervous
systems Endocrine system
  • Chemicals or ionizing radiation that cause or
    promote cancer
  • In US, approximately 1 in 2 men and 1 in 3 women
    will develop some form of cancer
  • In US, cancer kills about 560,000 people/year
  • Worldwide, approximately 6 million people/year
  • What is link between chemicals and cancer?
  • We dont know exactly, but 1 study in US est.
    8,000 cancer deaths from air pollution, 8,000
    from food additives and industrial products, and
    16,000 from occupational exposure
  • National Cancer Institute recognizes link between
    some cancer deaths and environmental pollution
  • Very difficult to make direct link
  • Often 10-40 years may elapse between initial
    exposure and appearance of detectable symptoms

18
Teratogens
Classes of toxic substances Mutagens Carcinogens ?
Teratogens Immune nervous systems Endocrine
system
  • Birth defects are physical (structural),
    biochemical, or functional abnormality
  • Examples include cleft palate, lack of limbs, or
    spina bifida
  • Estimated 7-12 of all newborns in US have birth
    defects
  • Agents that cause harm or birth defects to a
    fetus or embryo called teratogens. Examples
    include
  • Ethyl alcohol (low birth weight, developmental
    problems)
  • Radiation
  • Chemicals (e.g., Thalidomide)
  • We do not know what percentage of birth defects
    caused by chemicals in the environment

19
Immune nervous systems
  • Classes of toxic substances
  • Mutagens
  • Carcinogens
  • Teratogens
  • Immune nervous systems
  • Endocrine system
  • Immune System specialized cells and tissues that
    protect body against disease and harmful
    substances by forming antibodies that make agent
    harmless
  • Examples Dioxins and arsenic
  • Nervous system Brain, spinal chord, and
    peripheral nerves
  • Example snake venom is a neurotoxin
  • PCBs, mercury, and certain pesticides are examples

20
Endocrine System
  • Classes of toxic substances
  • Mutagens
  • Carcinogens
  • Birth defects
  • Immune nervous systems
  • ? Endocrine system
  • Complex network of glands that releases very
    small amounts of hormones into the bloodstream of
    humans and other vertebrate animals
  • Low doses of these messengers turn on and off
    bodily systems that control sexual reproduction,
    growth, development, learning ability, and
    behavior
  • Examples Dioxins at high levels are
    carcinogenic, at low levels may disrupt hormone
    receptors
  • Pthalates Softening agents added to plastics
    (e.g., IV bags, plastic milk jugs, pop bottles)
    act as estrogens and may be partly responsible
    for earlier onset of sexual maturity, affect male
    reproductive health, and probable human carcinogen

21
What do we know?
  • National Academy of Science estimates
  • Only bout 10 of 80,000 chemicals in commercial
    use thoroughly screened for toxicity
  • Only 2 adequately tested to determine whether
    they are mutagens, carcinogens, or teratogens
  • Even fewer tested for possible damage to nervous,
    endocrine, and immune systems
  • Worst toxics are persistent, bioaccumulative,
    toxic, and transport long distances

22
How do we monitor the problem?
  • Body burden data
  • Human health indicators (epidemiological approach)

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
23
Human health indicators
Source National Cancer
Institute
24
How do we regulate toxic substances?
  • More than 24 federal laws and a dozen federal
    agencies are concerned with regulating the
    manufacture, distribution, and disposal of toxic
    substances
  • CAA and CWA deal primarily with by-products,
    while toxic substances often relate to products
    we use/need
  • CAA and CWA include special provisions regulating
    toxic and other hazardous pollutants

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
25
Examples of types of toxics regulation
  • Classes of chemicals
  • Mode of exposure

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
26
Classes of chemicals
Types of toxic regulations ? Classes of
chemicals Mode of exposure Other toxic substances
  • Federal Insecticide, Fungicide, and Rodenticide
    Act (FIFRA) (agricultural chemicals)
  • Requires producers to conduct extensive
    toxicology tests in the laboratory and the field
    before applying to produce and sell new
    agricultural chemicals
  • Problem mandates testing for carcinogenicity,
    but does not mandate that a chemical be tested
    for some other significant risks, or synergistic
    effects

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
27
Mode of exposure
Types of toxic regulations Classes of chemicals ?
Mode of exposure Other toxic substances
  • Occupational and Safety and Health Act (OSHA)
    limits workplace exposure to unhealthy levels of
    toxics and other dangerous substances

28
Other toxic substances
Types of toxic regulations Classes of
chemicals Mode of exposure ? Other toxic
substances
  • Toxic Substances and Control Act (TSCA) (1976)
  • Catch all statutes regulates creation,
    manufacture, distribution of toxic substances
  • In contrast to FIFRA, does NOT automatically
    require producers to conduct extensive battery of
    tests, so most TSCA chemicals have not undergone
    broad testing
  • Producer must file pre-manufacture notification
    (PMN) with EPA before import or manufacture
    chemical not in currently in commercial use. EPA
    can approve or restrict
  • EPA also can examine chemicals that were in
    commercial use before law passed

29
What regulatory options?
  • Government can ban a substance, or permit
    production and attempt to control exposure
  • Government needs to decide on appropriate
    regulatory standard
  • Health-based approach
  • Feasibility approach
  • Use risk-benefit to regulate when risks outweigh
    social benefits

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
30
Health-based
  • Regulatory approaches
  • Health-based
  • Feasibility
  • Risk-benefit
  • Proscribe all risks or significant risks
  • Historic example of zero-risk approach is the
    Delaney Clause in the Federal Food Drug and
    Cosmetic Act (FFDC)
  • If food additive causes cancer in animals,
    Delaney Clause prohibits the additives use
  • Critics say unrealistic to ban something if only
    1 in billions chance of cancer
  • Defenders argue that most risks turn out to be
    worse than originally thought and require
    precautionary approach
  • Replaced in 1996 by Food Quality Protection Act
    (which amended FIFRA and FFDCA)does not use
    health-based approach, uses risk-based approach
  • Clean Air Act (NAAQs), Safe Drinking Water Act
    (Maximum Contaminant Level Goals) are other
    examples of health-based standards

31
Feasibility statutes
  • Regulatory approaches
  • Health-based
  • ? Feasibility
  • Risk-benefit
  • Reduce risk as technologically or economically
    feasible
  • OSHA
  • Congress requires agencies to reduce toxic health
    risks, but only to the extent feasible
  • Major question is what feasible means
  • Courts have ruled this means both economically
    and technologically feasible
  • Other examples include Clean Water Act and Safe
    Drinking Water Act (Maximum Containment Levels)

32
Risk-Benefit Statutes
  • Regulatory approaches
  • Health-based
  • Feasibility
  • ? Risk-benefit
  • FIFRA EPA must balance risks and benefits in
    determining whether a pesticide presents an
    unreasonable risk
  • Before registering pesticide, EPA must determine
    it will not pose unreasonable risk taking into
    account the economic, social, and environmental
    costs and benefits of pesticides.
  • Many environmentalists worry that statutes like
    FIFRA and TSCA that require EPA to balance risk
    and benefit may lead to paralysis by analysis
  • Risk-benefit analysis has many critics
  • Can slow down regulation and make it more
    difficult and thus less likely government will
    restrict harmful toxic substances
  • For example, under FIFRA it took EPA 17 years to
    carry out a review of pesticide Alar

33
Informational approaches
  • Public pressure and market choices to address
    problem
  • Emergency Planning and Community Right-to-Know
    Act of 1986 through TRI as we discussed earlier
    companies reduce toxic releases because they
    dont want to show up high on list
  • Problems include
  • Self-reporting can encourage companies to change
    reporting standards
  • May not require companies to report amount of
    toxics used or what is in their productsso
    ultimately may do little to reduce exposure to
    toxins

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
34
Precaution
  • Politically, truly precautionary regulation can
    be difficult to sustain
  • Under the precaution approach, some substances
    will be regulated that will eventually turn out
    to be relatively safe
  • Producers and consumers will likely cite false
    positives as evidence that the government is
    over-regulating

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
35
Future of toxics
  • We need new paradigm of toxic pollution
    policyonly fraction of EPAs resources devoted
    to prevention instead of end-of-pipe cleanup
  • European cxample REACH (Registration,
    Evaluation, and Authorization of Chemicals)
  • European Union policy based on precautionary
    principal
  • Standards for taking regulatory action much more
    proactive/precautionary than US policies

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
36
Bisphenol-A (BPA)
  • Widely used to make hard, clear polycarbonate
    plastics for baby bottles and sipping cups, water
    bottles, and food containers (most canned foods)
    (7 plastic that is clear and hard)
  • Trace amounts of BPA leach from polycarbonate
    containers into foods and liquids
  • 2003-4 study by CDC found detectable levels of
    BPA in 93 of urine samples collected from gt
    2,500 adults and children over 6
  • Last week US National Toxicology Program released
    draft report that rats fed or injected low doses
    BPA developed
  • precancerous tumors
  • urinary tract problems
  • reached puberty early
  • possibility that bisphenol-a may alter human
    development cannot be dismissed.

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
37
Bisphenol-A alternatives
  • In past week Nalgene announced will stop using
    BPA in their polycarbonate products
  • Many large Canadian retailers, including
    Wal-Mart, removing food-related products made
    with plastics containing BPA
  • Wal-Mart (and other retailers) have agreed to
    pull baby bottles made with bisphenol-a from its
    U.S. stores early next year
  • Other alternatives
  • Fresh (or frozen) vegetables alternative can
    liners used by some companies and Japan
  • Glass, porcelain and stainless-steel containers,
    particularly for hot foods and liquids
  • Several companies sell BPA-free baby bottles and
    sippy cups

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
38
MAINE CASE STUDYAn Act to Protect Childrens
Health and the Environment from Toxic Chemicals
in Toys and Childrens Products
  • Last week Maine Legislature passed and governor
    signed bill into law to track, and potentially
    ban, harmful chemicals in childrens products
  • LD 2048 requires Department of Environmental
    Protection to keep a list of chemicals it
    identifies as harmful
  • DEP identifies chemicals of high concern
  • Manufacturers of childrens products sold in
    Maine have to disclose if their products contain
    these chemicals
  • Could be required to replace the chemicals if
    safer, cost-effective alternatives exist
  • Maine is going to participate in interstate
    clearinghouse of information of what is in
    childrens products so others can learn from the
    states experience
  • Students in ES266 The Environment and Human
    Health (Prof. Carlson) helped to support this
    bill through class projects, including holding a
    public information session and talking with
    legislators

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
39
Brominated Flame Retardants
  • Common in plastics, electronics, textiles in
    furniture rugs foams used in mattresses
    furniture
  • BFRs in human breast milk rapidly increasing,
    threaten normal brain development in fetuses and
    children
  • Accumulating in people and animals
  • Policies to phase out have been adopted in EU,
    Sweden, Norway, Germany, Austria, China,
    Netherlands
  • Many corporations are switching to safer flame
    retardants
  • Maine Banned BRFs because similar to PCBs
  • First in nation law to ban some of these
    substances
  • Other states have now banned them also

Extent and impacts Toxicity factors and
classes Monitoring Regulation and information
40
Happy Earth Day ?
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