Air quality in Beijing `returns to pre-Olympic standards`

Air quality in Beijing has reverted to unhealthy levels just one year after the city staged a relatively smog-free Olympics, according to calculations.

An index measuring air quality that was published by the US embassy on social networking site Twitter has recorded unhealthy readings for the Chinese capital on an almost daily basis over the past few months.

The Beijing environmental protection bureau refused to comment when questioned by AFP about pollution in the city.

Nevertheless, officials did issue a statement, which said: "Our figures show air quality in the first half of the year and in July was better than last year."

Critics have pointed out however that the weather and even the economic downturn may have had an effect on the improved air quality statistics touted by the government.

In Guangzhou, meanwhile, authorities have pledged to improve air quality in the area in time for the country to host the 16th Asian Games next year.