Lethal air pollution rises in emerging nations

International experts are warning that potentially lethal air pollution has boomed in fast- growing big cities in Asia, South America in recent decades.

While Europe has managed to drastically cut some of the most noxious pollutants over the past 20 years, emerging nations experienced the opposite trend with their fast growth, scientists at the UN's meteorological agency said.

Their comments came ahead of World Meteorological Day tomorrow, which this year has the theme "the air we breathe".

In 2005, the WHO estimated that deaths rates in cities with higher particle pollution were 15 to 20 per cent above those found in cleaner cities.

"Particulate matter is of great concern in cities," said Liisa Jalkanen, atmospheric environment research chief at the World Meteorological Organisation.

"In Asia many cities such as Karachi, New Delhi, Kathmandu, Dacca, Shanghai, Beijing, and Mumbai they exceed all the limits... Also several cities in South America such as Lima, Santiago, Bogota.

The worst city in Africa is Cairo," she told journalists. Len Barrie, director of WMO research, said restrictions set up in Europe after concern about acid rain emerged in the 1980s have cut concentrations of another pollutant, sulphur dioxide, there "by a factor of 20."

"In other areas where economic growth has leapt forward, such as Asia, China, India, the opposite is true," he added.