Beijing's first snowfall this winter has helped reduce the pollution level. The air pollution index (API) dropped from a high of 247 on Tuesday to 162 Wednesday, meteorological authorities said.

Photo taken on December 10, 2008 shows the snow-covered Mutianyu section of the Great Wall located on the outskirts of Beijing, capital of China. The first snow of this winter fell in Beijing on Wednesday. [Xinhua]

A cold front is forecast for the capital in the coming week and will further reduce the API to about 100, barring a big change in emissions, Li Xin, chief engineer of the Beijing municipal environment protection bureau, said.

"Beijing is surrounded by three mountain ranges and the coming rain, winds and snow could have a positive impact on the capital's air quality," Li said.

She said the pollution index is still high.