Chemicals that Compromise Life:
A Call to Action
World Wildlife Fund, September 1998
Half a century ago, scientists made the unsettling discovery that man-made compounds, such as
the pesticide DDT, accumulate in the bodies of people and wildlife. Today synthetic chemical
contamination is pervasive and global. There is no clean, uncontaminated place and no person
untouched by this chemical legacy. Each of us now carries several hundred synthetic
chemicals that were not present in the bodies of our great grand-parents at the turn of the century.
The question of how contaminants affect health has become all the more urgent since scientists
recently recognized a new kind of hazard known as "endocrine disruption." Through a series of
accidental discoveries, researchers stumbled on the fact that some widespread, man-made
chemicals, called "endocrine disruptors," can interfere with the body’s own hormones and
jeopardize health.
In the past five years, the scientific investigation of this problem has intensified and provided
steadily growing evidence linking these synthetic endocrine-disrupting compounds to impaired
health in wildlife and people. This exploration is ongoing and far from complete.
Although uncertainties remain about the impact of these compounds on human health, the
emerging science has heightened concerns and provided sufficient evidence of damage to
wildlife to justify immediate protective measures. The time has already come for precautionary
action to reduce our reliance on suspect chemicals and to establish screening and testing
programs to assess chemicals for hormone-disrupting hazards.
A conversation disrupted
Hormones, which are produced in a variety of organs known as endocrine glands, travel in the
bloodstream carrying messages from one part of the body to another. In adults, these hormone
messages govern sex and reproduction and also coordinate organs and tissues that work in
concert to keep the body functioning properly.
Before birth, hormone signals play an even more vital role: They orchestrate critical events in
early development, such as sexual differentiation and the proper construction of the brain.
Because hormones are so key in early development, synthetic chemicals that disrupt such
internal messages pose a particular hazard to the unborn. Studies also have found that
contaminant exposure levels that cause no apparent damage to adults can have devastating
effects on those exposed in the womb. In one study, a fetus proved 100 times more sensitive to a
hormone-disrupting contaminant than an adult.
Normal development depends on getting the right amount of the right chemical messenger to the
right place at the right time. If these messengers don’t arrive or arrive in the wrong amounts, the
offspring’s development is irreparably altered. Disruption at this stage of life can cause
permanent damage with consequences that last a lifetime.
A New Kind Of Hazard
Until recently, the research and regulation of synthetic chemicals focused primarily on the
dangers of genetic mutation, cancer, and gross birth defects. In probing endocrine disruptors,
scientists are investigating entirely new mechanisms and novel avenues through which synthetic
chemicals can upset normal biological processes and undermine health and well-being. Evidence
is
mounting that endocrine disruptors can do damage at extraordinarily low doses—measured in
parts per trillion—and that they are already compromising the health and intelligence of the next
generation.
The problem of endocrine disruption centers on synthetic chemicals that sabotage the body’s
internal communication system. In the body’s constant conversation with itself, a large part of
the communication takes place through hormones and other chemical messengers (see "A
Conversation Disrupted," above).
Endocrine disruptors can upset the body’s internal communication in several different ways.
Many man-made chemicals mimic natural hormones and send false messages. Other synthetic
compounds block hormone receptors that receive the messages traveling in the bloodstream and
prevent true messages from getting through. Some cause disruption by preventing the synthesis
of the body’s own hormones or by accelerating their breakdown and excretion. Whatever the
mechanism, the bottom line is the same: Any chemical that interferes with hormones can
scramble vital messages, derail development, and undermine health.
The 1996 book Our Stolen Future, by WWF senior scientist Dr. Theo Colborn with coauthors
Dianne Dumanoski and Dr. John Peterson Myers, documents the emerging scientific case on
these hormonally active chemicals and the hazard they pose to wildlife and people. Wildlife
studies and laboratory experiments provide solid evidence that synthetic chemicals have
contributed to dwindling wildlife populations by disrupting hormones, altering sexual
development, impairing reproduction, and undermining the immune system. Taken as a whole,
the broad body of evidence also shows that people are not only at risk, but already affected.
Studies have documented health effects in people at exposures only slightly higher than
"background levels" considered typical in the human population.
Although the investigation of human health effects has hardly begun, researchers have already
found immune system changes, neurological and motor delays, and learning problems in children
exposed in the womb to background levels of PCBs, a family of hormone-disrupting, persistent
contaminants. (See "Scientific Assessment Work Sessions," below). Epidemio-logical studies
are also documenting disturbing trends showing that people are increasingly suffering from
health problems seen in wildlife and laboratory animals that have been exposed to synthetic
endocrine disruptors. This growing human evidence includes reports of declining sperm counts
in some parts of the world, rising rates of benign prostatic enlargement and testicular cancer, and
an increasing incidence of other genital defects in males.
No one knows how many of the tens of thousands of synthetic chemicals in general commerce in
the United States pose such a hazard, because none have been screened specifically for hormonal
or message-disrupting activity. To date, scientists have identified more than 70 individual
chemicals or chemical families that disrupt hormones or undermine development. About half
of these are persistent compounds that resist degradation, accumulate in fat, and become
concentrated in the food web. Over decades, such persistent contaminants can accumulate in a
woman’s body fat and provide a source of exposure for an unborn child or nursing infant. These
hormone-disrupting chemicals are found literally everywhere—in household products beneath
the kitchen sink and in the fat of polar bears in the remote Arctic. In daily life, one encounters
hormonally active compounds in pesticides, detergents, cosmetics, plastic toys, and food
containers. These compounds are pervasive contaminants in our food
and in every ecosystem on Earth.
The Growing Proof
Evidence from Wildlife
Wildlife studies have been an important part of the case against endocrine disrupting chemicals
since the problem first emerged. This body of scientific evidence is already substantial and has
continued to grow. In recently published studies, scientists have reported some striking new
findings:
Florida alligators. The alligators in Florida’s Lake Apopka have been a regular feature in
news coverage of the endocrine disruption issue because of their dramatic symptoms: stunted
penises that are sometimes only one-third normal size. But skeptics had doubted the broader
significance of the Lake Apopka studies by researcher Lou Guillette and his colleagues, because
it was assumed that the reproductive problems stemmed from a chemical accident that dumped a
pesticide into the lake. A new study highlights the hazards of chronic contamination and shows
that the problem of hormone disruption and reproductive problems in alligators extends beyond
Lake Apopka. The discovery of alligator hormone abnormalities and reproductive failure in other
Florida lakes that have not had chemical accidents makes it clear that chronic contamination may
be as hazardous to wildlife as acute incidents.
Great Lakes fish. New studies have made a persuasive case that contaminants were in part or
wholly responsible for the loss of the lake trout in the 1950s. Fishery officials had blamed the
crash of the native lake trout on habitat destruction, overfishing, and predation by an introduced
parasite, the sea lamprey. However, University of Wisconsin researchers implicated dioxin
contamination in the extinction when they showed that the developing trout in the egg die with a
concentration of as little as 5 parts per trillion of toxicity equivalents of dioxin and dioxin-like
PCBs. Using core samples from lake sediment and computer models, U.S. Environmental
Protection Agency (EPA) scientists have concluded that dioxin contamination reached a level
high enough to begin killing trout developing in eggs and undermining trout reproduction in the
1940s.
Albatross in the North Pacific. An investigation of albatross nesting in a "pristine"
environment on remote Midway Island has underscored the global nature of the chemical
contamination problem. In a recent study, researchers reported the startling news that these longlived seabirds in the middle of the North Pacific carry combinations of persistent contaminants
such as PCBs, furans, and dioxins that are known to cause reproductive and health effects in
Great Lakes fish-eating birds.
Whales in the North Pacific. A study of contamination in North Pacific minke whales found
an upward trend in contaminants such as PCBs and the pesticide chlordane between 1987 and
1994. This contradicts the widespread impression that PCBs and chlordane are old problems that
already have been addressed. The research team concluded that increasing levels indicate a
"continuous fresh input of PCBs and [chlordane] in the North Pacific marine environment."
Otters in the Columbia River. Recent work on free-living otters has shown that mammals are
also at risk from chemical contamination. Researchers from the National Biological Service
found delayed or inadequate development of the reproductive tract in male otters as well as a
significant dose-response relationship between these problems and synthetic contaminants such
as certain PCBs, dioxins, and pesticides. The more heavily contaminated young males had
smaller bones (baculums) within their penises and lighter testicles than others who were less
contami-nated. In this study, the animal with the highest levels of synthetic contaminants had no
testicles at all.
Evidence from Laboratory Experiments
Although wildlife studies have been invaluable, they have inherent limitations. They document
associations or correlations between health problems and particular man-made contaminants
without being able to establish for certain whether a particular chemical is, indeed, responsible
for the observed effect. Laboratory studies have, therefore, played an important role in the
development of the endocrine-disruption issue by confirming the links between contaminants
and health problems seen in the field and by providing insight into how synthetic contaminants
cause this damage. Controlled laboratory studies have also helped answer whether the
contaminant levels encountered in the environment are high enough to warrant concern. The
recent laboratory work on endocrine disruption has opened two important new lines of
investigation:
Contamination from plastic. Recent studies have heightened concerns about hormonedisrupting compounds that leach from plastics and have demonstrated that some chemicals
widely encountered in plastics pose a hazard even at very low doses. In ongoing mouse studies,
researchers found that doses of bisphenol A (an ingredient in the lining of metal food cans,
polycarbonate water jugs, and dental sealants applied to children’s teeth) comparable to the
amounts currently ingested by people can alter the development of the male reproductive organs.
Male mice whose mothers were exposed to bisphenol A at levels as low as 2 parts per billion
showed changes that would cause them to have permanently enlarged prostate glands. At doses
of 20 parts per billion, they showed a permanent 20 percent decrease in daily sperm production.
Developmental damage from PCB exposure. Laboratory experiments with rats have identified
the ear as a particularly sensitive target for prenatal disruption from the persistent contaminants
PCBs and have added weight to the theory that PCBs do their damage by disrupting thyroid
hormones, which are vital to proper development of the brain and nervous system. The studies
done by the EPA lab in Research Triangle Park, North Carolina, found that PCB exposure during
early development caused permanent auditory deficits, particularly in the ability to hear the
lowest frequencies. The researchers suggest that this loss may reflect the effects of thyroid
disruption on the development of the cochlea in the inner ear. Because this research confirms that
PCBs interfere with thyroid hormones, it would also explain why other studies have implicated
these persistent contaminants in behavioral disorders such as attention deficit and hyperactivity
and in learning problems.
Evidence from Human Studies
The greatest uncertainties about endocrine disruptors concern people and the question of how
great a toll hormone-disrupting synthetic chemicals are taking on human health. In most cases,
there is no way to answer these questions definitively because there is no unexposed population
to study as a control group and because scientists do not for ethical reasons conduct experiments
on people. Nevertheless, compelling new findings are emerging in this research arena:
Contaminated fish and learning problems.
An ongoing study by researchers at Wayne State University has documented significant
deficits in intelligence and learning in children exposed to PCBs and other contaminants in the
womb. Drs. Joseph and Sandra Jacobson found significant learning and attention problems in
children of women who had eaten contaminated fish from Lake Michigan in the six years prior to
pregnancy. In their most recent examination of these children at 11 years of age, they found the
most highly exposed have difficulty paying attention, suffer from poorer short- and long-term
memory, were twice as likely to be at least two years behind in reading comprehension, and were
three times as likely to have low IQ scores. This work is striking not only because of the lasting
impact seen in children, but also because the fish-eating mothers were not highly contaminated.
The levels measured in their bodies fall on the high end of what is considered the "normal"
background range for PCBs in the human population. In a similar study at the State University of
New York (Oswego), researchers found measurable neurobehavioral deficits in the newborn
children of women who had eaten the equivalent of 40 pounds of Lake Ontario salmon in a
lifetime, thereby replicating the Lake Michigan study. In additional tests, these children showed
abnormal reflexes, a shorter attention span, and an intolerance to stress. The Oswego study has
been the first to document a wide range of effects on temperament stemming from prenatal
exposure to contaminants.
The role of PCBs and dioxin in learning and behavior problems. In a review of the
scientific evidence on contaminants and human health, a branch of the U.S. Public Health
Service recently concluded that PCBs and dioxins are responsible at least in part for the
neurological and behavioral deficits reported in children exposed in the womb. This assessment
by the Agency for Toxic Substances and Disease Registry based this judgment on "remarkable
parallels" in the human epidemiological evidence and corroboration from wildlife and laboratory
evidence: "[T]he collective weight of the evidence indicates that certain PCB/dioxin-like
compounds found in fish...can cause neurobehavioral deficits. Further, the evidence indicates
that these compounds have produced some effects in some Great Lakes fish consumers."
Genital defects. A recent medical study reports rising rates of genital defects in male infants
in the United States, which—together with similar reports of increasing incidence from five
European countries—indicates a disturbing health trend. The study, which used data from two
surveillance systems tracking birth defects, found that the rate of hypospadias, a defect involving
misplacement of the urethra, doubled between 1970 and 1990. This defect arises from
incomplete masculinization of the male genitals and has been replicated in the laboratory with
anti-androgens such as DDE and vinclozolin (a commonly used fungicide on fruits and
vegetables).
Testicular cancer in young men. In recent decades, the incidence of cancer of the testicles in
men under age 34 has been increasing rapidly in many countries and poses a challenge to
epidemiologists trying to determine the cause. According to recent studies, this cancer in young
men almost certainly arises from events early in life or even in the womb—a hypothesis
supported by the higher rate of testicular cancer among men with developmental defects such as
hypospadias and undescended testicles. Researchers also note that striking geographical
variations in the pattern of this disease point to the importance of environmental influences.
Another clue has come from animal studies, which support the theory that estrogens may play a
key role in promoting testicular cancer and raise the question of whether synthetic chemicals that
mimic estrogen are contributing to soaring testicular cancer rates.
Declining sperm counts. Seeking to resolve the contentious debate about whether the reported
worldwide decline in male sperm counts is indeed real, a team of reproductive epidemiologists
recently conducted an exhaustive reanalysis of all the data in a 1992 Danish study. The team,
headed by Dr. Shanna Swan, concluded that the dramatic sperm count drop of about 50 percent
described in that study may, in fact, be more severe than initially reported. In their study, Swan
and her team determined that the data showing this loss are not, as some critics have contended,
a product of bias or confounding variables. "Further analysis of these studies supports a
significant decline in sperm density in the United States and Europe," according to Swan and her
colleagues.
The Urgent Pursuit of Answers
The ongoing research on endocrine disruption has provided some answers, but it has also
revealed gaps in current knowledge and raised a host of new questions. There is a pressing need
to fill these gaps and move ahead with studies that will answer outstanding questions and thereby
further confirm the case regarding hormone disrupting synthetic chemicals.
The dramatic decline reported in human sperm count may be a sign that endocrine disruptors
already have had a broad impact on the human population. It is, therefore, urgent that researchers
tackle unresolved questions and gain a better understanding of what is happening. A major
international sperm count study is beginning to investigate many unresolved questions and
controversies surrounding this issue. The question of why sperm counts seem to have declined
much more sharply in some places than others may provide a particularly fruitful line of
investigation. If this geographical variation is, indeed, genuine, it may make it possible to
identify environmental factors responsible for falling sperm numbers.
The impact of contaminants on the developing brain, nervous system, and behavior should be a
top research priority. Up to now, the discussion of the endocrine-disruption problem has tended
to focus on disrupted sexual development and reproductive problems such as declining sperm
counts and genital defects. The recent studies that link learning and behavior problems in
children to contaminant exposure in the womb demonstrate the need to broaden the focus beyond
reproductive problems.
Focusing on Low Doses
Research to date has yielded two critical lessons: Hormonally active chemicals can do damage at
extremely low exposure levels, and these compounds do not behave according to the classic
linear dose-response model that informs traditional toxicology.
These findings underscore the absolute necessity of focusing on very low doses in research and
in any screening program. In hormone systems, high-dose responses do not predict hazard at
much lower doses nor does adult response predict the impact on those exposed in the womb.
Studies have, in fact, shown that an extremely low dose can produce a far greater effect than a
high dose, depending on time of exposure.
Focusing on Species of Special Concern
Frogs. Plagued by grotesque deformities such as missing eyes and limbs in the United States
and by epidemic die-offs in several parts of the world, frogs are unquestionably in trouble and
warrant special scientific attention. While they are not at all fragile, frogs may be particularly
vulnerable because their permeable skin allows them to absorb the chemicals they encounter
more readily than other animals. Chemical contaminants have emerged as the leading suspect in
the investigation of frog deformities. The demanding process of metamorphosis, which is
orchestrated by thyroid hormones in concert with other modulating hormones, may also put frogs
at risk from persistent synthetic chemicals, especially those known as endocrine disruptors.
Persistent compounds may accumulate in the frog’s fat and be released again into the
bloodstream when the frog calls on these reserves for metamorphosis, thereby exposing the
developing frog to accumulated contaminants at the worst possible time. This disruption could
lead to a host of problems, including impaired immune systems that would make frogs
vulnerable to disease and epidemic die-off.
Marine mammals. The movement of contaminants in the environment puts dolphins and
porpoises at particular risk and warrants increased investigation. Contamination from man-made
chemicals continues to increase in marine environments because synthetic chemicals released
over the past half century are making their way to the oceans and seas. Marine mammals already
carry concentrations of PCBs and related compounds known to disrupt thyroid hormones in
people and sabotage the development of children exposed in the womb. These contaminants can
impair brain development and undermine the offspring’s immune system. Because studies have
shown that PCB exposure in the womb also leads to low-frequency hearing loss, increasing PCB
contamination poses a unique hazard to whales, which depend on hearing for navigation and
communication.
Focusing on Human Groups at Special Risk
There is an urgent need for research to assess the impact of endocrine disrupting contaminants on
those human populations at particular risk, especially indigenous peoples who continue
subsistence hunting and fishing and rely on food from the top of the marine food web. Initial
studies have found that Inuits living in the Canadian Arctic carry much higher levels of
contaminants than do people living in polluted industrial areas. These studies have documented
alarming health problems, such as impaired immune systems and high rates of ear infections in
Inuit children. In the United States, American Indians living on the Great Lakes have been
warned to discontinue traditional fish harvests because of the contamination in the fish.
A recent study in Mexico also has raised concerns about the hazard that heavy pesticide use
poses to children’s brain development. The risk of endocrine disruption and developmental
damage is likely to be higher in tropical countries because of the intense use of pesticides, yet
very little research has been done there. This question deserves immediate scientific attention.
Product Testing
Although animal studies have raised worrisome questions about contaminants in food, plastic
containers, and other consumer products, surprisingly little testing has been done on substances
encountered in daily life. Product testing for contaminants deserves to be a much higher research
priority.
In Europe, several national governments have tested children’s plastic teething rings and toys
and found that some were, indeed, leaching hormonally active chemicals. In several countries,
these toys and teething rings have been removed from the market.
Elsewhere, independent consumer groups have filled in the breach. In the United States, the
Consumers’ Union recently tested baby foods for dioxins, PCBs, and related compounds and
also tested seven brands of plastic wrap for adipates and phthalates, two families of plasticizers
that affect development and reproduction. A Japanese consumer group has done its own testing
of six brands of plastic baby bottles. At the very least, consumers should have information about
which plastics leach possibly hormonally active compounds, so they can avoid exposure to them
if they choose. For information about reducing exposure from these chemicals, visit the
Netsurfer’s Guide to Hormone-disrupting Chemicals on WWF-Canada’s Web site at
<http://www.wwfcanada.org>. See also "Tips for Reducing Your Exposure, below".
Tips for Reducing Your Exposure
To reduce exposure to endocrine-disrupting chemicals—
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Wash your hands before eating.
Eat lower on the food web.
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Eat a wide variety of fruits and vegetables to vary your exposure to pesticides.
When heating food, use heat-resistant glass or ceramic containers instead of plastic
containers or plastic wrap.
Minimize plastic wrap’s direct contact with food. In particular, reduce consumption of fatty
foods (cheese and meat)
packaged in plastic and heat-sealed containers.
Drink distilled water.
Don’t use pesticides in your home or on your lawn or garden. Try to use natural methods:
1. Use traps, parasites, and natural predators such as ladybugs.
2. Use disease- and pest-resistant plants.
3. Use compost and mulch to improve soil health and reduce the need for pesticides
and fertilizers.
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Avoid areas freshly sprayed with pesticides.
If you golf, keep your hands, tees, and golf balls away from your mouth because most golf
courses are sprayed intensively.
Buy mercury-free or rechargeable batteries and dispose of them properly. (Check with your
local government for hazardous waste disposal sites.)
Rising to the Challenge
The mounting scientific evidence confronts us with disturbing questions about the extent to
which hormonally active synthetic chemicals are altering our children’s ability to learn, to
function in a social environment, to resist disease, and to reproduce. The integrity of the next
generation is on the line. Our response should reflect the true magnitude of these stakes.
Indeed, we need nothing less than a high-powered, well-funded scientific research project on
endocrine disruptors and human health—an international, independent research initiative that
would move ahead with a real sense of urgency, unrestrained by corporate or government
influences.
Coming to grips with this threat will require a shift to different ways of making judgments about
environmental contaminants and a new standard for taking action. There is little chance of
showing a simple cause-and-effect link between one or more groups of hormone-disrupting
chemicals and problems such as declining human sperm counts that may be due to exposure to
contaminants in the womb. To protect public health in the real world—where people are exposed
to complex mixtures of chemicals and where the consequences may not surface until decades
later—we need to assess research results based on "the weight of the evidence." This approach
relies on accumulating evidence and common sense inferences rather than on scientific ideals of
proof that are more appropriate to controlled laboratory experiments. Such a commonsense
judgment led to the conclusion that cigarette smoking causes lung cancer long before the link
was demonstrated conclusively.
The stakes in the endocrine-disruption problem could not be higher. If the hazards are as great as
some research indicates, delaying control and elimination of hormone-disrupting compounds
means continuing irreversible damage to the next generation. Given the disturbing questions
raised by the emerging science, it is unconscionable to proceed with business as usual. The
magnitude of possible harm to the environment and human health makes a precautionary
approach wise and necessary. Even though scientific uncertainties remain about the hazards
posed by hormone-disrupting compounds, more than enough is known
to act now.
Scientific Work Sessions
The case against hormone-disrupting synthetic chemicals rests on an extensive body of evidence
drawn from many different fields and types of scientific work—wildlife studies, lab experiments,
mechanistic investigations at the molecular and cellular level, reports on contamination levels in
people and wildlife, and human data, including the tragic medical episode with the synthetic
estrogen DES. Ten years ago, World Wildlife Fund senior scientist Dr. Theo Colborn took on the
task of synthesizing all of the widely scattered studies in an effort to understand the implications
for human and wildlife health.
As part of this, Colborn and her colleagues have over the years convened six meetings to bring
together experts from a wide variety of disciplines to review evidence and assess hazards. At the
end of each of these meetings, the participants have agreed on a consensus statement detailing
their conclusions about the state of the science and their judgment about human risk. For
example:
July 1991: The first of these historic meetings, at the Wingspread Conference Center in Racine,
Wisconsin, focused on reproductive hazards to wildlife and people. The consensus statement
concluded that endocrine-disrupting compounds have already damaged many wildlife
populations by causing thyroid dysfunction, decreased fertility, decreased hatching success,
behavioral abnormalities, feminization and demasculinization in males, and compromised
immune systems. Moreover, people in many parts of the world are being exposed to the same
synthetic chemicals that have disrupted development in wildlife and laboratory animals. Unless
these chemicals are controlled, the Wingspread statement warned, we face the danger of
widespread disruption in human embryonic development and the prospect of damage that will
last a lifetime.
December 1993: A second meeting at Wingspread on developmental problems in wildlife
concluded that "Declines in a number of species and many taxa (including plants) are in progress
on the North American continent. Some of these declines are related to exposure to man-made
chemicals. Such declines are not solely a U.S. or North American problem but are
occurring on a global scale."
February 1995: A third meeting at Wingspread, examining hazards to the developing immune
system, concluded that "The potential exists for widespread immunotoxicity in people and
wildlife species because of the worldwide lack of appropriate protective standards.... The risk of
suspected immuno-modulators is sufficient to warrant regulatory approaches that would limit
exposure."
July 1995: Scientists meeting at Wingspread to assess the hazard that synthetic contaminants
pose to fish populations warned that "many fish populations in both saltwater and freshwater are
presently threatened by chemicals introduced into the environment through human activities.
There is a high degree of certainty that some wild fish populations have already been affected."
This expert consensus recommended action to "safeguard fish stocks from the effects of
synthetic chemical exposures. The general public and many scientists are not aware of the extent
to which fish species, including economically important fisheries, are presently at risk or have
already been injured."
November 1995: A panel of international experts meeting in Erice, Sicily, warned that levels of
endocrine-disrupting compounds found in the environment and in people threaten brain
development. This group of prominent scientists from a variety of disciplines relating to the
nervous system, brain development, and behavior stressed the extreme sensitivity of the
developing brain to chemical disruption and the danger of permanent damage, which can show
up in attention-deficit problems, reduced intelligence, learning disabilities, and intolerance to
stress. More broadly, the experts agreed that "widespread loss of this nature can change the
character of human societies or destabilize wildlife populations."
September 1996: At the sixth meeting at Wingspread, the participants reached consensus that
exposure to contemporary-use pesticides is greater than most people think and that effects of
such exposure remain little studied. Exposed populations include farm workers, communities
downstream and downwind of agricultural areas, wildlife, and consumers of food products.
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WWF’s Global Toxics Campaign
Scientific work in the field of endocrine disruption is a key component of WWF’s Global Toxics
Campaign, which also concentrates on persistent organic pollutants (POPs) and agricultural
pesticides. Although each area—wildlife contaminants, POPs, and pesticides—has unique
characteristics, they are closely connected. Many POPs are endocrine disruptors, and
several pesticides are both endocrine disruptors and POPs. The main difference among the three
endeavors is in their approach:
The wildlife contaminants program focuses on addressing the evolving science of endocrine
disruptors and other toxic chemicals.
The POPs program centers its work on policy development and advocacy, such as aiming for
the phaseout and elimination of the most deadly, persistent pollutants like DDT, PCBs, and
dioxins.
The agricultural pesticides program, in collaboration with farmers and growers, promotes
integrated pest management (IPM) and other ecologically sound alternatives to the use of
pesticides.
The Global Toxics Campaign is one of several initiatives that WWF has launched to address
global threats to the Earth’s environment posed by unsustainable timber trade, overexploited
fisheries, the profligate use of toxic chemicals that harm wildlife, and unrestrained emissions of
greenhouse gases that contribute to global warming.
Addressing global threats is one of the three strategies pursued by WWF in its Living Planet
Campaign—a call to action tomake the close of this century and the opening of the next a turning
point in the worldwide struggle to save endangered species, protect important harbors of
biological diversity, and encourage changes in international policies and markets that contribute
to
environmental threats. To learn more about WWF’s Global Toxics Campaign and the Living
Planet Campaign, visit our Web site at <http://www.worldwildlife.org.>.