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Pringle lecture (Ecl 6080): 26 October 2009. Understanding and Controlling Persistent Organic Pollutants (POPs): An important, yet neglected, dimension of Conservation Biology?. Persistent organic pollutants (POPs) A. Historical perspective on synthetic chemicals
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Pringle lecture (Ecl 6080): 26 October 2009 Understanding and Controlling Persistent Organic Pollutants (POPs): An important, yet neglected, dimension of Conservation Biology?
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 DDT first synthesized PCBs synthesized 1889 First reports of skin disease linked to POPs 1900 --------------------------------------------- Industrial scale production of PCBs 1948 Paul Muller receives Nobel Prize 1950---------------------------------------------- 1959 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 1998 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 • aldrin • chlordane • DDT • dieldrin • endrin • heptachlor The Dirty Dozen: 7. mirex 8. toxaphene 9. PCBs 10. hexachlorobenzen 11. dioxins 12. furins
Effects on Wildllife: The Laurentian Great Lakes Toronto Chicago
Sixteen top predators in the Laurentian Great Lakes have reproductive problems Birds:Fishes: 1. Bald eagle 1. Lake trout 2. Black crowned night heron 2. Sauger 3. Caspian tern 4. Common tern Reptiles: 5. Double crested cormorant 1. Snapping turtle 6. Forster’s tern 7. Herring gull Mammals: 8. Osprey 1. Beluga whale 9. Ring-billed gull 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 Double- Crested 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
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 lab- oratories 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 (perfluoro- chemicals, 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 togo 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 tedx@tds.net for full list of web sites -www.ourstolenfuture.org