For cleaner air

thirty-two nations from across Europe and North America have agreed to reduce airborne emissions from three heavy metals and ban or limit 16 of the world's most dangerous chemicals. The legally-binding phase-outs were signed at a summit in Aarhus, Denmark, by environment ministers from across Europe, Central Asia and North America. The summit was sponsored by the United Nations.

Heavy metals can cause blood, liver and kidney disorders. The chemicals -- persistent organic pollutants (pops) -- are used in agriculture or industry, and are produced as a by-product of waste incineration or industrial processes. They can contaminate areas thousands of kilometres from their source and linger for years in the environment and in fatty body tissues with insidious and deadly health effects, including birth defects, infertility and cancer.

Many industrialised countries have agreed to control or ban these pops. They are still widespread in developing countries, used as pesticides or produced when hazardous waste is burnt in the open air releasing carcinogenic dioxins. The Aarhus protocols are expected to take effect by the year 2000.

The protocols would boost chances of achieving a worldwide ban by the year 2000 on emissions of heavy metals and 12 pops, said Swedish environment minister Anna Lindh.