'Dirty dozen' chemicals banned at last

Posted: 17 May 2004

The Stockholm Convention on Persistent Organic Pollutants (POPs), a global treaty aimed at banning 12 of the most dangerous persistent organic pollutants (POPs), becomes legally binding today, 17 May 2004. In signing the Convention, governments agree to take measures to eliminate or reduce the release of POPs into the environment.

The countdown to the treaty's entry into force was triggered on 17 February 2004 when France became the 50th state to ratify the agreement.

"Of all the pollutants released into the environment every year by human activity, POPs are the most dangerous. For decades these highly toxic chemicals have killed and injured people and wildlife by inducing cancer and damaging the nervous, reproductive and immune systems. They have also caused uncounted birth defects," said Klaus Toepfer, Executive Director of the United Nations Environment Programme (UNEP).

"By committing governments to eliminating production and environmental releases of these chemicals, the Stockholm Convention will greatly benefit human health and the environment. It will also strengthen the overall scope and effectiveness of international environmental law," he said.

Governments will pursue a rapid start to action under the treaty when they meet for the first session of the Conference of the Parties to the Convention (COP 1) in Punta del Este, Uruguay in early 2005.

One of the meeting's priorities will be to assist countries combat malaria by replacing DDT with safe and effective alternatives. The meeting will also establish a Committee for evaluating other chemicals and pesticides that could be added to the initial target list of 12 POPs (these are aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex, toxaphene, polychlorinated biphenols or PCBs, hexachlorobenzene, dioxins and furans).

Another key goal will involve promoting "best environmental practices" and "best available techniques" that can reduce or eliminate releases of dioxins and furans (perhaps the most toxic of all the POPs) from a wide range of industrial and other sources.

Arctic contaminated

Every human in the world carries traces of these chemicals in their bodies. POPs are highly stable compounds that can last for years or decades before breaking down. They circulate globally through a process known as the "grasshopper effect". POPs released in one part of the world can, through a repeated process of evaporation and deposit, be transported through the atmosphere to regions far away from the original source.

In addition, POPs concentrate in living organisms through another process called bioaccumulation. Though not soluble in water, POPs are readily absorbed in fatty tissue, where concentrations can become magnified by up to 70,000 times the background levels. Fish, predatory birds, mammals, and humans are high up the food chain and so absorb the greatest concentrations. And when they travel, the POPs travel with them.

As a result of these two processes, the Inuit and the animals they consume in the Arctic - thousands of kilometers from any major POPs source - suffer particularly high levels of POPs in their bodies. But POPs are equally dangerous to people working with pesticides or living near POPs sources, particularly in developing countries, where a lack of equipment and expertise leads to accidental exposures.

Most of the 12 chemicals will be banned immediately. However, the use of DDT for disease vector control under World Health Organization guidelines is considered an acceptable purpose because it is still essential in many countries to control malaria transmission by mosquitoes. This will allow governments to protect their citizens from malaria - a major killer in many tropical regions - until they are able to replace DDT with chemical and non-chemical alternatives that are cost-effective and environmentally-friendly. It is hoped that the Convention will help direct research and development towards more effective means of malaria control.

Cleaning up stockpiles

In addition to banning uses, the treaty focuses on cleaning up the growing accumulation of unwanted and obsolete stockpiles of pesticides and toxic chemicals. Dump sites and toxic drums from the 1950s, '60s, and '70s are now decaying and leaching chemicals into the soil and poisoning water resources, wildlife, and people.

In the case of PCBs, although they are no longer produced, hundreds of thousands of tons are still in use in electrical transformers and other equipment. Governments have until 2025 to phase out these uses, which gives them time to arrange for PCB-free replacements. Not later than 2028, governments must dispose of these PCBs in an environmentally sound manner.

Fortunately, there are alternatives to POPs. The problem is often that high costs, a lack of public awareness, and the absence of appropriate infrastructure and technology have often prevented their adoption.

To ensure such alternatives, donors have pledged hundreds of millions of dollars in new funding over the next several years. The Global Environment Facility, a major donor, has already mobilized resources to support POPs projects in more than 100 countries. Backed by an alliance of developed and developing countries - and with both industry and environmental groups on board - the Stockholm Convention holds the promise of a POPs-free world for future generations.

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