Protocol restricting the emission of cadmium, lead and mercury has come into effect as part of a U.N. treaty to protect air quality in Europe.

A protocol restricting the emission of three harmful heavy metals - cadmium, lead and mercury - has come into effect as part of a United Nations treaty to protect air quality in Europe.

The Protocol on Heavy Metals, ratified by 18 countries and the European Union, is the seventh under the Convention on Long-range Transboundary Air Pollution of the U.N. Economic Commission for Europe. It aims to cut emissions from industrial sources (iron and steel, and non-ferrous metal industries), combustion processes (power generation and road transport) and waste incineration.

"Heavy metals obviously are something that cause great concern for the global environment because they travel throughout oceans," Werner Obermayer of the UN Environment Programme said. "We have recorded cases where heavy metals are found in fish, which make up the bulk of protein intake for people in coastal areas and the Arctic region." He noted that in Europe, fish is an important food source in the Nordic countries.

Adopted in June 1998 in Aarhus, Denmark, the Protocol requires parties to reduce their emissions of cadmium, lead and mercury to below 1990 levels , or alternatively, between 1985 and 1995. See www.unece.org/env/lrtap/hm_h1.htm.