More than 1,500 people have contacted China's environment ministry to urge rapid changes in the way it monitors pollution, amid accusations authorities are underplaying the problem.

The ministry said last month it was planning to amend the way it measures air quality to include the smaller particles that experts say pose the greatest health risk, inviting the public to comment on the proposal.

Public anger over heavy pollution in China has been compounded by official data saying air quality is good, or only slightly polluted, when smog is visible and figures published by the US embassy rank it as "very unhealthy".

Chinese authorities currently use a method known as PM10, focusing on larger particles in the air.

But the environment ministry has proposed adopting the system favoured by the US embassy, which measures the smallest and most dangerous airborne pollution, known as PM2.5.

The ministry also said it was proposing to include ozone readings and "set tighter rules for some pollutants already monitored, such as PM10 and nitrogen oxide", although the changes would not be fully implemented until 2016.

A statement on the environment ministry website dated Tuesday said it received more than 1,500 submissions in the 21-day consultation period ended December 5.

"The suggestions generally favoured the proposal that the revised Ambient Air Quality Standards should include PM2.5," it said.

However, the official China Daily newspaper said Thursday that many of the messages the ministry received called for faster action.

Some environmental campaigners say authorities are unwilling to adopt the PM2.5 standard nationwide yet because under that system, far fewer Chinese cities would be able to claim that their air quality was satisfactory.

"The main fear is that once PM2.5 is monitored, the mayor of the city will look bad," said Zhou Rong, a Beijing-based Greenpeace spokeswoman.

"The leaders of the monitoring stations report to the Environmental Protection Bureau, which in turn reports to the government and the mayor. They will not do things to make their boss lose face," she added.

The China Daily has said in the past that if PM2.5 were used as China's main standard, only 20 percent of Chinese cities would be rated as having satisfactory air quality, against the current 80 percent.

On Thursday the paper urged the government to respond to public pressure, which comes in the same week thick smog in Beijing forced the cancellation of hundreds of flights at the world's second-busiest airport.

"Simply sticking our heads in the sand so we can't see the sky won't make the problem disappear. The government needs to be brave enough to face up to the problem," the paper said in an editorial.