By Geoffrey Lean, Environment Editor

Acid rain caused by sulphur dioxide spewed from factories and power plants affected a third of China's vast land mass last year, posing a threat to food safety, according to a Chinese parliamentary report.

More than half the 696 cities and counties monitored had suffered acid rain, in some cases on a daily basis, the official Xinhua news agency said.

"Increased sulphur dioxide emissions meant that one third of China

Discharge of sulphur dioxide in booming China rose by 27 per cent between 2000 and 2005 to 25 million tonnes, making the country the world's top emitter of the pollutant.

Sheng told lawmakers the sulphur dioxide emissions were double the acceptable limit.

China has pledged to install desulphurisation facilities in coal-burning power plants and is planning pilot emissions trading schemes to help improve air quality. The capital, Beijing, has promised to replace its notorious smog with clear skies in time for the 2008 Olympics.

Source Independent Online Edition