In a rare piece of good news about the global environment, the accord will ban, phase out or severely cut back a range of industrial chemicals and pesticides that linger in soil and water for decades.

The Bush administration -- facing a storm of international criticism for its environment policy, especially its rejection of the Kyoto Protocol on global warming -- declared on April 19 that it would stand by the Clinton government's signature of the POP accord.

These pollutants pass up the food chain and accumulate in the body's fatty tissues, becoming a suspected source of allergies, birth defects, cancer and damage to the immune system and reproductive organs.

The treaty, which will be known as the Stockholm Convention on Persistent Organic Pollutants (POPs), was finalised in Johannesburg last December after a marathon lasting two and a half years.

"This is a historic achievement," UN Environment Programme (UNEP) spokesman Michael Williams told AFP by phone from Geneva. "We have the chance of getting rid of some of the most toxic substances ever made by Man."

"Every person in the entire world carries traces of POPs," said Swedish environment ministry spokeswoman Anette Toernqvist. "This is the first step taken on an international level. Until now, all efforts have been conducted on a national or EU level."

The dozen toxic chemicals comprise eight pesticides (aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex and toxaphene); two industrial compounds (polychlorinated biphenols (PCBs) and hexachlorobenzene, which is also a pesticide); and two byproducts of combustion and industrial processes (dioxins and furans).

These chemicals are alarming not just because they resist biodegradation and are toxic -- they are also highly mobile, able to circulate around the world in what is called the "grasshopper effect".

Under this, POPs can be picked up in water evaporation, taken along by wind, deposited on the land or in the sea and then picked up again and deposited again, to places far from the original source.

As a result, they can end up in the tissues of people living thousands of kilometers (miles) from any major POP source, such as the Arctic, where POP concentrations among native Inuits are high because their staple diet includes fatty seal meat.

The Convention will immediately ban most of the "Dirty Dozen" although an exemption on health grounds has been granted to DDT, which is still needed by poor tropical countries to combat malarial mosquitoes.

Countries will be able to retain DDT until they find alternatives that are cheap and environmentally friendly.

PCBs, which were widely used as an insulative fluid in electrical transformers, will likewise get a reprieve because of the high cost, in many countries, of replacing the equipment.

PCBs are no longer produced, but "hundreds of thousands of tonnes" are still in use, UNEP says. Governments will have until 2025 to phase them out, but must maintain existing equipment in a way that prevents leaks. In addition, some countries have been given specific delays for phasing out other chemicals.

The Convention sets up control mechanisms to cover the production, import, export, disposal and use of POPs, and makes money available to developing countries to wean them off these chemicals, and opens the possibility of adding other POPs to the list.

Environment groups say they are happy with the arrangement.

"To lay down a benchmark that has elimination as a goal is a real step forward for the international community," Clifton Curtis, director of the Global Toxics Initiative at the WWF, said here Friday.

The ceremonies start on Tuesday with a gathering of environment ministers or senior officials from 123 countries, followed by formal signature of the Convention on Wednesday.

The treaty will become legally binding once it has been ratified by 50 countries, a process likely to take several years.

Canadian Environment Minister David Anderson will submit Canada's instruments of ratification as he signs the treaty, a possibly unique event in diplomacy that has been made possible by an exceptional decision of parliament in Ottawa.

The Bush administration -- facing a storm of international criticism for its environment policy, especially its rejection of the Kyoto Protocol on global warming -- declared on April 19 that it would stand by the Clinton government's signature of the POP accord.

Copyright © 2001 AFP

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