Beijing - Major indicators are absent in China's air quality reports, and the public is poorly informed about how the pollution is damaging their health, a report released on Wednesday said.

The Air Quality Information Transparency Index said the country's cities lagged behind their international counterparts in terms of the comprehensiveness of air quality indicators used in monitoring and public reporting. The index was generated by Renmin University of China's law school and the Institute of Public and Environmental Affairs.

The most important indicator overlooked is the measuring of "fine particles" - particles fewer than 2.5 micrometers in diameter (PM2.5).

Institute of Public and Environmental Affairs director Ma Jun said PM2.5 poses the greatest health risks of all particles.

"These can end up deep in the lungs, and transfer noxious gases and heavy metals directly into the blood," he said.

A report released in 2009 by the Committee on the Medical Effects of Air Pollutants, an advisory body of the UK's Department of Health, said an increase of 10 micrograms per cubic meter in the ambient annual average level of PM2.5 is associated with a 6-percent increase in death rates in a typical Western European and North American population.

But none of the cities selected from the Chinese mainland officially published the PM2.5 figure, although nearly all international cities selected in the research did.

Information about carbon monoxide, ozone and volatile organic compounds, which are typical among the list of indicators to be monitored, are also absent from most Chinese cities' measurements. The information is public in developed countries and regions.

Consequently, cities on the Chinese mainland generated an average score of 22.65 on the Air Quality Information Transparency Index, compared with an average score of 79 in international cities.

Beijing tops the domestic city's list with a score of 38.

"The report sends a clear message: the public has a right to be informed about air pollutants that can harm their health," Chinese Research Academy of Environmental Sciences research fellow Wang Xianliang said.

He said environmental authorities had already deliberated the pressing concerns and propositions in the report but must work out many practical and procedural complexities before a national policy change can be adopted.

"Take PM2.5 as an example: we cannot use a one-size-fits-all policy to gauge air quality in different cities and regions, given China's vastness and geographical diversity," he said.

The public has already identified part of the problem and voiced their concerns. In the past few months, Beijing residents have complained the official air quality rating system underreports pollution's severity.

On Dec 1, the air quality in Beijing was categorized as "slightly polluted" by municipal authorities but "heavily polluted" by the US embassy in Beijing, which independently monitors the air quality near its compound.

Wang said the increased density of monitoring stations, the inclusion of more suitable indicators and strengthened communication with the public will boost public confidence and enhance the credibility of air quality information released by government agencies.

Wu Wencong and Li Yao contributed to this story.

China Daily