Transcript Document

Pringle lecture (Ecl 6080): 26 October 2009
Understanding and Controlling
Persistent Organic Pollutants (POPs):
An important, yet neglected, dimension
of Conservation Biology?
I.
Persistent organic pollutants (POPs)
A. Historical perspective on synthetic chemicals
B. Effects in wildlife (2002 Global Assessment EDCs)
C. Effects on humans
-body burdens in newborns (EWG 2005 report)
II. Measuring toxicity
A. acute versus chronic
B. lethal vs sublethal
-sublethal (reproductive, development
and growth, behavior, immune system
III. Policy
A. How can we regulate POPs?
-reforming federal law
-Stockholm Convention
B. How can we stop the international trade
in hazardous/toxic wastes?
-Basel Convention
Historical perspective:
There are over 100,000 synthetic chemicals on the market most largely produced since World War II.
Federal regulation of production of these chemicals very
fragmentary
By the early 1970s - warning signs of environmental problems
-DDT - bird and bald eagle deaths
(Rachel Carson’s Silent Spring)
-DES - widely used drug which caused cancer
-PCBs - killing birds and fish
Unfortunately the above problems were viewed more
as isolated cases:
a few rogue chemicals had wrecked havoc…so
ban DDT, ban DES, ban PCBs
By introducing so many substances that
did not evolve with living organisms
over hundreds of millions of years,
…have we unwittingly initiated changes
in our biology that may be damaging it
profoundly?
POPs TIMELINE (1870-2001)
1850---------------------------------------------1874
1881
1889
DDT first synthesized
PCBs synthesized
First reports of skin disease linked to POPs
1900 --------------------------------------------1929 Industrial scale production of PCBs
1948 Paul Muller receives Nobel Prize
1950---------------------------------------------1959
1962
1966
1972
1979
1996
1998
Peak of DDT use in the US
Rachel Carson’s Silent Spring is published
Wildlife damage reported
US bans DDT
US bans manufacture of PCBs
Theo Colburn’s Our Stolen Future is published
Convention on POPs
2000--------------------------------------------2001 Stockholm Convention on POPs
What are Persistent Organic Pollutants (POPs)?
• Chemicals that resist biodegradation, with a tendency to acculate
in the food chain, and which are very mobile - moving around
the globe in a grasshopper effect - via repeated cycles of
evaporation, wind and deposition
The Dirty Dozen:
1.
2.
3.
4.
5.
6.
aldrin
chlordane
DDT
dieldrin
endrin
heptachlor
7. mirex
8. toxaphene
9. PCBs
10. hexachlorobenzen
11. dioxins
12. furins
Effects on Wildllife: The Laurentian Great Lakes
Toronto
Chicago
South shore of Lake Michigan - Sulfur capital of the world
Sixteen top predators in the Laurentian Great Lakes
have reproductive problems
Birds:
1. Bald eagle
2. Black crowned night heron
3. Caspian tern
4. Common tern
5. Double crested cormorant
6. Forster’s tern
7. Herring gull
8. Osprey
9. Ring-billed gull
Fishes:
1. Lake trout
2. Sauger
Reptiles:
1. Snapping turtle
Mammals:
1. Beluga whale
2. Mink
3. Otter
Lake trout declines
attributed to predation
by introduced
sea lamprey.
………What is the
role of POPs ?
Chinook salmon
deaths linked to bacterial
kidney disease
Male Kestrels dosed with pesticides are
smaller and less dominant than un-dosed
Deformities in DoubleCrested Cormorant
in Great Lakes
Shell thinning of
cormorant eggs resulting
from exposure to DDT
Subtle effects of toxic poisoning result in large
populations of relatively resistant species like gulls
Effects on Wildlife: The St. Lawrence Belugas
• Heavily contaminated with mercury, lead, DDT, PCBs, Mirex,
and many other pesticides;
• >50 ppm PCBs = toxic waste
• St. Lawrence Beluga’s - the living dead?
Dicofal spill into stream draining
into Lake Apopka, FL, results
in reproductive abnormalities
in alligators and population
decline of 90%
Polar Bears
-reproductive problems
-altered levels of
testosterone,
progesterone,
vitamin A, and
thyroid hormones
-suppression of immune
system
-only Pacific Northwest
orcas, Baltic Sea seals
and St. Lawrence
River belugas have
been found with higher
doses of PCBs than
polar bears in
Svalbard, Norway
EFFECTS ON HUMANS:
In a study spearheaded by the EWG, researchers at two major laboratories found an average of 200 industrial compounds, pollutants,
and other chemicals in 10 newborn babies, with a total of 287
chemicals found in the group.
The chemicals found in newborns
include:
organochlorine pesticides (DDT and dieldrin)
chemicals currently or formerly used in a wide
range of consumer products (perfluorochemicals, brominated fire retardants, PCBs)
chemical pollutants from waste incineration and
fossil fuel combustion (polyaromatic
hydrocarbons, polychlorinated and
polybrominated dioxins and furans,
polychlorinated naphthalenes, mercury).
EPA's policies on toxic chemicals largely
target cancer.
EPA with no formal policy regarding
childrens' vulnerability to chemicals
that damage the immune system, the
brain, or the hormone system, kidney,
liver, lungs, thyroid or a host of other
potential targets, even though plenty
of evidence says that children face
higher risks for harm.
From a regulatory perspective, fetal exposure to
industrial chemicals is quite literally out of control.
• U.S. industries manufacture and import
approximately 75,000 chemicals, 3,000
of them at over a million pounds per year.
• Studies show that hundreds of industrial
chemicals circulate in the blood of a baby
in the womb, interacting in ways that are
not fully understood.
• Many more pollutants are likely present in the
womb, but test methods have yet to be
developed that would allow health officials to
comprehensively assess prenatal exposure to
chemicals, or to ensure that these exposures
are safe.
The Reason:
• The Toxic Substances Control Act (TSCA) is our
nation's notoriously weak chemical safety law.
• TSCA deprives the EPA of the most basic regulatory tools
The vast majority of chemicals in use today do not have
anywhere near sufficient data needed to assess their
safety, particularly their safety for the unborn baby or
young child.
• Under TSCA, the EPA cannot require this data as a
condition of continued chemical use. Instead, the EPA
must negotiate with industry or complete a formal "test
rule" for every study that it needs, for every chemical on
the market. Consequently, very few high quality toxicity
tests are conducted.
The EWG study and a strong body of supporting science
suggest that fetal exposure to industrial chemicals is
contributing to adverse health effects in the human
population.
Experience indicates that it is never too late to take
action. Blood levels of PCBs and pesticides like DDT are
lower today than 30 years ago when they were banned.
Since these watershed actions in the 1970s, however,
few industrial chemicals have been regulated to any
significant degree.
Recommendations of EWG Report
The various reasons for this stagnation — the need for
data on chemical toxicity and exposure, lack of ambition
at the EPA, and chemical industry intransigence — all
come back to one central cause:
the absence of a strong federal chemical safety
law that provides the EPA with unambiguous
statutory authority to take the actions needed to
ensure that chemicals are safe.
SO
How can we regulate POPs on a
national level?
• Federal law must be reformed to ensure that children
are protected from chemical exposures, and that to the
maximum extent possible exposure to industrial
chemicals before birth be eliminated entirely.
• The nation's pesticide law was amended nearly a decade
ago to require explicit protection of infants and children
from pesticides.
• Actions taken under the 1996 Food Quality Protection Act
(FQPA) have reduced or eliminated children's exposures
to a number of highly hazardous pesticides, with no
discernable adverse impact on the availability or price of
a wholesome food supply, and without adverse impact
on the agricultural or pesticide industry.
• We recommend a similar standard be applied to
commercial chemicals.
This would mean transforming TSCA into a true public
health and environmental law, with the following core
provisions. A new TSCA would:
• Require chemical manufacturers to demonstrate
affirmatively that the chemicals they sell are safe for
the entire population exposed, including children in
the womb. In the absence of information on the risks
of pre-natal exposure, chemicals must be assumed
to present greater risk to the developing baby in utero,
and extra protections must be required at least as
strict as the 10 fold children's safety factor in FQPA
• Require that the safety of closely related
chemicals, such as the perfluorochemicals
used to make Teflon and other stain-resistant
and water repellant products, be assessed as a
group. The presumption would be that these
chemicals have additive toxicity unless
manufacturers clearly prove otherwise.
• Grant the EPA clear and unencumbered
authority to demand all studies needed to
make a finding of safety and to enforce clear
deadlines for study completion.
• Remove from the market chemicals for which
tests demonstrating safety are not conducted.
• Eliminate confidential business protection for
all health, safety, and environmental information.
• Require that material safety data sheets provided
to workers contain the results of studies conducted
under these provisions.
• Provide strong incentives for green, safer chemicals
in consumer products and industrial processes.
Results of this EWP
Investigation raise
questions with respect
to the role of exposures
in utero both in a range
of children's health
problems and in diseases
developed in adulthood
that may have their
origins in early life
exposures
International regulation: Objectives
of the Stockholm Convention
•Elimination of intentionally produced POPs
-DDT
• Elimination and reduction of unintentionally produced POPs
-dioxins
• Disposal of POP wastes
• Identification and regulation of new POPs
- penta BDE
- lindane
-others (difocal, endosulfan and perfluorinated chemicals)
Stockholm Convention on POPs (cont):
• First global legally binding instrument whose aim is to protect
Human health and environment by controlling production, use
and disposal of toxic chemicals
• Has helped classify chemicals that are especially toxic
(established the dirty dozen
• Signed by 151 countries; ratified by 119 countries
• US has signed but the current administration is stalling
on ratification
How can we curb the international
trade in toxic and hazardous wastes?
Objectives of the Basel Convention on
Control of Transboundary Movements of
Hazardous Wastes and their Disposal:
• International treaty designed to reduce the movements
of hazardous waste between nations, and specifically to
prevent transfer of hazardous waste developed to less
developed countries (LDCs).
• Basel Ban Amendment prohibits the export of hazardous
waste from a list of developed countries to developing
countries. The Basel Ban applies to export for any reason,
including recycling; not yet in force but considered
morally binding by signatories
The Basel Convention (cont):
• 166 countries have signed the convention which was entered
into force in 1992
• US has not ratified convention (neither has Haiti, Afghanistan)
• US is strongly opposed to Basel Ban, as is Canada and
many industry groups
• 61 nations have ratified the Basel Ban; 62 nations needed for
it to go into effect
Current issues in the international
movement of hazardous wastes
• E-waste
• Ship-breaking
Exercise your purchasing power
and make informed choices:
-baby products (Tiny Footprints website)
-Environmental Working Group’s website
-www.pesticide.org
-email [email protected] for full list of web sites
-www.ourstolenfuture.org