Happy Earth Day
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First Earth Day
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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
Toxic Substances
ES118 Spring 2008
Love Canal
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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
Love Canal--Impact
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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
Aftermath of Love Canal
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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)
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What happened?
– >44,000 sites evaluated, by 2004 about 1,200 active NPL sites, and about
900 cleaned up and/or removed
– >$27 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
Overview
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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
Extent and impacts
Toxicity factors and classes
Monitoring
Regulation and information
The chemical revolution
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The number and amount of chemicals substances sold
commercially in the US has grown dramatically
How widespread a
problem?
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35,000 chemicals used daily in US industry
– 500-1,000 new chemicals created annually
– 120,000 US establishments create and distribute
chemicals
– <7% proposed for manufacture % EPA reviewed
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> 20,700 pesticides used in US, and >1.2
billion lbs of pesticides produced annually,
with >890 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
Are toxic substances
unique?
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Many are valuable for agricultural,
industrial, or consumer products
– We often don’t 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
Toxicity response
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Type and amount of health damage
– Acute toxicity: Immediate or rapid reaction
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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
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Examples: Mesothelioma, rare form of cancer from
exposure to asbestos
Extent and impacts
Toxicity factors and classes
Monitoring
Regulation and information
What factors affect
toxicity?
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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
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How well a person can detoxify a substance
Genetic makeup of a person
Synergistic responses: Response can be greater
Extent and impacts
than sum of individual chemicals
Toxicity factors and classes
Monitoring
Regulation and information
Classes of toxic
substances
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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
Mutagens
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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
Carcinogens
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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
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What is link between chemicals and cancer?
– We don’t 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
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Very difficult to make direct link
– Often 10-40 years may elapse between initial exposure and
appearance of detectable symptoms
Teratogens
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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
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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)
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We do not know what percentage of birth defects
caused by chemicals in the environment
Immune &
nervous
systems
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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
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Nervous system: Brain, spinal chord, and
peripheral nerves
– Example: snake venom is a neurotoxin
– PCBs, mercury, and certain pesticides are
examples
Endocrine System
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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
What do we know?
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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
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Worst toxics are persistent,
bioaccumulative, toxic, and transport long
distances
How do we monitor the
problem?
Body burden data
 Human health indicators
(epidemiological approach)
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Extent and impacts
Toxicity factors and classes
Monitoring
Regulation and information
Human health
indicators
Source:
National Cancer Institute
How do we regulate toxic
substances?
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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
Examples of types of
toxics regulation
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Classes of chemicals
Mode of exposure
Extent and impacts
Toxicity factors and classes
Monitoring
Regulation and information
Types of toxic regulations
 Classes of chemicals
Mode of exposure
Other toxic substances
Classes of chemicals
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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
Mode of exposure
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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
“Other” toxic
substances
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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
What regulatory options?
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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
Health-based
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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 additive’s 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
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Clean Air Act (NAAQs), Safe Drinking Water Act (Maximum
Contaminant Level Goals) are other examples of health-based
standards
Feasibility statutes
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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
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Other examples include Clean Water Act
and Safe Drinking Water Act (Maximum
Containment Levels)
Risk-Benefit Statutes
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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.”
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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
Informational approaches
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Public pressure and market choices to address
problem
Emergency Planning and Community Right-toKnow Act of 1986 through TRI as we discussed
earlier companies reduce toxic releases because
they don’t 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 products—so ultimately may do little to
reduce exposure to toxins
Extent and impacts
Toxicity factors and classes
Monitoring
Regulation and information
Precaution
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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
Future of toxics
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We need new paradigm of toxic pollution
policy—only fraction of EPA’s resources
devoted to prevention instead of “end-ofpipe” 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
Bisphenol-A
(BPA)
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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 >
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:
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precancerous tumors
urinary tract problems
reached puberty early
“possibility that bisphenol-a may alter human
Extent and impacts
development cannot be dismissed.”
Toxicity factors and classes
Monitoring
Regulation and information
Bisphenol-A
alternatives
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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
MAINE CASE STUDY:
An Act to Protect Children’s Health and the
Environment from Toxic Chemicals in Toys and
Children’s Products
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Last week Maine Legislature passed and governor signed bill
into law to track, and potentially ban, harmful chemicals in
children’s 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 children’s 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 children’s products so others can learn
from the state’s experience
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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
Brominated Flame Retardants
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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
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Maine: Banned BRFs because similar to PCBs
– First in nation law to ban some of these substances
Extent and impacts
Toxicity
factors and classes
– Other states have now banned them also
Monitoring
Regulation and information
Happy Earth Day
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