Toxic Chemicals and the Ramsar Convention

by Barbara Rutherford, WWF International


This paper was first presented as one of the Themes for the Future special interventions at the 6th Meeting of the Conference of the Contracting Parties in Brisbane, in March 1996, and was published in volume 9 of the Proceedings of that COP. It provides an eloquent statement of the problems and threats presented by the growing prevalence of toxic substances and makes some concrete suggestions as to how the Ramsar Convention can respond. More recently, Ms Rutherford and her colleague Peter Hurst discussed these issues with the Ramsar Scientific and Technical Review Panel in April 1997 and agreed upon a joint programme for building these concerns into the work of the Convention and possibly providing guidance for the Contracting Parties, to be discussed at the 7th COP in Costa Rica.

This text has been slightly edited to disguise its origins as an oral presentation to the plenary session of the COP. -- Web Editor


This paper concerns taking toxics out of wetlands as an emerging issue for the Contracting Parties to the Ramsar Convention on Wetlands to be considering in their future work to conserve wetlands and water resources. Pollution is not really an emerging issue, as many Contracting Parties are already experiencing degradation of their water resources, and of their Ramsar and other wetland sites due to agricultural run-off and industrial discharges.

What is perhaps emerging, however, is a new understanding of how toxic pollution damages nature, including humans. What follows from this new understanding is an imperative to prevent pollution from occurring in the first place, as many of the impacts we are now beginning to understand are long term and irreversible in nature.

It is becoming increasingly clear that the world's biodiversity cannot be conserved in a world filled with harmful chemicals. Toxic chemicals move through air and water, into earth and plants and animals, and have been detected in wildlife from the Arctic to Antarctica - in alligators, bald eagles, bottle-nosed dolphins, beluga whales, great blue heron, common seals, polar bears, sea turtles, and humans, among many other species.

For decades, wildlife have sent warning signs about the dangers of chemical pollution. These dangers first caught widespread attention in 1962 with Rachel Carson's book, Silent Spring, which focused mainly on older generation organochlorine chemicals, many of which are still in commerce, and their ability to kill wildlife and have serious sub-lethal impacts, such as on reproduction and immune system functioning.

Today, many scientists agree that many synthetic chemicals are capable of tampering with the fundamental endocrine systems of humans and wildlife, which control development and reproduction through chemical messengers called hormones. Such impacts may have profound effects at the population level of many species. WWF US Senior Scientist, Dr Theo Colborn, tells the fascinating endocrine disruptor story in her new book, Our Stolen Future, coauthored with Dr. Meyers and Dianne Dumanoski. This chilling tale was published last week in the US and will be available in the UK, France, Germany, Australia, and Japan before the year is out.

And yet synthetic chemical use continues to increase worldwide. From 1940 to 1982, production of synthetic materials increased roughly 350 times. US production of synthetic organic compounds was approximately 435 billion pounds, or 200 billion kilograms, in 1992. Global production is estimated to be four times greater - about 1700 billion pounds, or about 800 billion kilograms, per year. While pesticide use is highest in North America and Europe today, pesticide use is expected to increase at a greater rate in developing countries in the near future.

Many of these compounds are persistent and bioaccumulative, magnifying up the food chain - often absorbed in body fat - where they can wreak havoc for a long time, through multiple generations passed down from mother to offspring.

Wildlife - and humans - are daily being exposed to a multitude of synthetic chemical compounds that disrupt development of the reproductive, immune, nervous, and endocrine systems by mimicking hormones, blocking the action of hormones, or by other unknown interference with the endocrine system. Hormones play a key role in development, and especially sexual differentiation.

In mice, elephants, whales, humans, and in all other mammals, as well as in birds, reptiles, amphibians, and fish, the process that creates two sexes from initially unisex embryos is guided by these chemical messengers. They are the conductors that give the cues at the right moment as tissues and organs make now-or-never choices about the direction of development. In this central drama in which boys become boys and girls become girls, hormones have the starring role.

Consequently, endocrine disruption may endanger populations because their immune systems are not functioning well and they cannot recover from infections. Or their ability to obtain sufficient food or avoid predators could be affected. There is also evidence that endocrine disruptors cause the loss of parenting instinct in some bird species. Abnormal sexual development of anatomy or behaviour because of endocrine disruption can also put populations at risk of not being able to reproduce in sufficient numbers.

Glaring examples include:

Alligators exposed to a pesticide spill in Florida have suffered severe reproductive impairment: male alligators have significantly smaller penises (one third to one half the normal size) compared to males hatched on a relatively cleaner lake.

This contamination has also decimated the local red-eared turtle population. Reproductive difficulties are showing up by an absence of males and the presence of many specimens that are neither male nor female - so-called "intersex." Although sex differentiation in turtles is determined by temperature, research has shown that something more than temperature fluctuation is needed to produce sexually confused animals. In laboratory experiments it has been demonstrated that intersex animals can be produced by exposing them to estrogen or estrogen-mimics such as PCBs.

Surveys of the critically endangered Florida panther have found similar effects. The panthers' range in southern Florida - including the Everglades National Park and the Big Cypress Swamp - is downstream from major agricultural areas. A significant number of the male animals have some form of reproductive abnormality, including undescended testicles, and over-production of estrogen. Both males and females have problems of sterility, evidence of impaired immune response, and malfunctioning of thyroid glands.

Marine mammals may be most at risk. There has been a series of mass die-offs of marine mammals in many different regions since the 1980s, including bottlenose dolphins along the Atlantic coast of the US, striped dolphins in the Mediterranean, harbour porpoises in the Black Sea, humpback whales in the western North Atlantic, and dolphins on the Texas coast. Most of these die-offs have been linked to high levels of PCBs found in the dead animals, although it is difficult to determine whether other synthetic chemicals were a cause as well. The endangered beluga whales of the St. Lawrence estuary are now among the most contaminated animals on earth, with tumours, reproductive problems, and heavy metal poisoning.

Experiments conducted in the Wadden Sea, where there are declining numbers of harbour seals, demonstrate that impaired reproduction is strongly related to levels of PCBs in seal tissue and strongly correlated to consumption of contaminated fish.

Adverse impacts have been recorded in populations of herring gulls, birds of prey and shorebirds. In 1970, in Ontario, Canada, it was discovered that 80% of the herring gull chick population died before they were hatched and had evidence of gross deformities, such as having adult feathers instead of down, club feet, missing eyes and twisted bills.

Also in the early 1970s in Southern California, researchers discovered that the female gulls were pairing up to nest together.

Even though DDT and dieldrin use was restricted in the USA in the early 1970s, poor reproduction continues to plague eagles in many areas of the USA. In 1993, bald eagles nesting along the Great Lakes produced deformed chicks with crossed bills and malformed feet. Similar defects have been found among other bird species in Oregon. Pesticide residues found in birds of prey in Africa and South America, where DDT is still widely used, indicate that this pesticide is taking a similar toll on wildlife in other parts of the world.

Plummeting numbers of shorebirds, including such species as sandpipers, including such species as sandpipers and plovers, in the mid-80s have also rung alarm bells. Shorebirds can travel well over 15,000 miles in a single year, from breeding sites in the Arctic to wintering grounds in South America. US data suggests that the population of sanderlings moving south along the East Coast of the US has declined approximately 80% over the past 15 years. Much of this population winters in Peru and Chile. Scientists surveying this population in Peru noted that the birds congregated every day to feed and bathe at the mouths of the rivers and streams that empty intensely cultivated river valleys in the otherwise harsh Peruvian desert. Almost all of the streams reeked of pesticides used in the cotton and rice fields nearby.

Fish species are also sensitive to endocrine disruption. For example, the lake trout, which became extinct in the Great Lakes in the 1950s, has been shown to be very sensitive to dioxins and PCBs when exposed as an embryo.

Several species of salmon introduced into the Great Lakes all have severely enlarged thyroid glands, which is strong evidence of hormone disruption. Salmon in Lake Erie show a variety of reproductive and developmental problems, for example, early sexual development and a loss of the typical male secondary sex characteristics, such as heavy protruding jaws and red coloration on the flanks.

Leading amphibian experts strongly suspect endocrine disruption as a cause for the frog declines which do not have an obvious explanation, such as habitat disruption or drought. Wind contaminants are suspected in high altitude declines, especially as many persistent organic pollutants leap-frog across the globe, recondensing in cooler spots and coming to rest until disturbed and sent on their journey again towards colder climates.

All of these warning signs from wildlife show us that appearances can be deceiving. The abnormalities in the alligator populations were only discovered because of a survey to consider the impacts of supplying wild alligator eggs for ranching. The pesticide spill which caused the contamination occurred in 1980, 14 years before the discovery of the defects. By this time, the water appeared to be clean according to ordinary water quality standards. Although toxics may be absent from the water, they are still present circulating through the food chain and causing severe problems. Other alligators which immigrated from outside the lake were giving the impression that all was well.

Scientists agree that human beings are being affected by compounds of this nature, too. Evidence of a 50% reduction in sperm counts during the past 50 years around the world and significant increases in sperm deformity, testicular cancer, breast cancer, as well as of cases of undescended testes, and endometriosis, are particularly worrisome. We are after all at the top of the food chain.

This new evidence demonstrating that even low doses of toxic chemicals - even the newer non-persistent chemicals - can permanently alter the neurological, immune and reproductive systems of wildlife and humans, calls for a renewed vigilance about keeping toxics out of wetlands, which ultimately means keeping toxics out of the environment.

The Ramsar Convention provides a framework within which the toxic threats to wetlands should be addressed. Many of the principles articulated in the Convention, such as wise use, environmental impact assessment, and ecological character, should include recognition of the harmful impacts of toxics. A WWF Discussion Paper for the Brisbane COP identified three specific recommendations concerning the implementation of these concepts. We encourage the Contracting Parties to resolve that toxics use in and around wetlands is incompatible with wise use and is a significant threat to the maintenance of their ecological character.

Current testing of synthetic chemicals is clearly inadequate, and our focus on cancer has led us to miss more subtle, sub-lethal effects. Although better testing protocols are urgently needed, more innovative approaches are required which recognize that the surest way to reduce risk is to reduce use.

Contracting Parties should therefore take note of global, regional and national initiatives, based on the Precautionary Principle, on the phasing-out of persistent organic pollutants and on toxics use reduction, including pesticide reduction and cleaner production. They should consider the use of publicly accessible toxic chemical inventories known as "pollutant release and transfer registers" (PRTRs) to track chemical use and release and endeavour to incorporate this work into their chemicals management programmes and integrate it with their conservation of wetlands and water generally.

WWF is continuing to work to strengthen corporate environmental reporting requirements by promoting the introduction of publicly-accessible chemical inventories worldwide and by supporting research and pilot projects in developed and developing countries to assess the potential for chemical inventories to stimulate reduced toxics use, to ensure that community groups will have the capacity to use this information when it becomes available, and to assist communities in obtaining this information where it is not yet available. For example, one promising WWF community right-to-know initiative is linked to a Ramsar wetland site - Lake Nakuru, Kenya - where there is evidence of toxic contamination.

Although there is a clear need to phase out the production and use of many of the persistent organic pollutants as soon as possible, the publicly accessible toxic chemical inventory tool holds so much promise for tracking toxic pollution and encouraging toxics use reduction precisely because it is a community tool. Everyone has the right to know about toxics use in their communities and everyone has a vested interest in ensuring the safest management and use of those toxic chemicals. Other promising initiatives, such as government and community partnership initiatives in the Netherlands, Sweden, Denmark and the Great Lakes to reduce pesticide use by measurable targets of at least 50%, demonstrate that much pesticide use is simply unnecessary.

The main message for those working in the field of protecting the environment and biodiversity is that it is no longer sufficient to approach population and species revitalization passively by providing appropriate habitat and expect threatened or extirpated populations to recover. Contamination of habitat is not always visible and may not cause immediate death of organisms that live in that habitat. Instead, contaminants may cause population-threatening changes in the way an organism functions in its environment. Animals that may appear to be healthy may be suffering from invisible damage which impairs their ability to withstand otherwise tolerable stresses or to rebound after natural disasters. For no apparent reason, they may suddenly disappear or slowly, imperceptibly slip into extinction. Toxic chemicals are thus a major long-term threat to biodiversity and may be an immediate threat to endangered species. WWF hopes that the Ramsar Convention will take this message seriously and that the Contracting Parties will find concrete ways to weave pollution prevention into their workplans for wetlands protection in the future.


Ramsar Recommendation 6.14 (COP6, 1996)

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