These cities have reduced sulphur dioxide emissions but they have been facing the challenge of addressing transport-related emissions, said the report.
The report, "Urban Air Pollution in Asia Cities," said that air quality has improved in some Asian cities, but pollution remains a threat to health and quality of life in others.
The report, "Urban Air Pollution in Asia Cities", was released on the eve of the first governmental meeting on urban air quality, held last December 13-14 in Yogyakarta, Indonesia, as part of the Better Air Quality 2006 workshop.
The report studied 22 Asian cities and one of its key findings is that the concentration of the fine particulate matter, called PM10, is "serious" in some countries in Asia.
One of the main threats to health and life is fine particulate matter-known at PM10 and PM2.5- "that enters our lungs and stays there for some time," said Dr. Dieter Schwela, one of the book's authors.
"There is a strong association between fine particulate matter and health issues in Asia as there is in Europe and the United States, but in Asia the concentrations of particulate are much higher," he said.
Dhaka, Hanoi, Surabaya, and Kathmandu have "limited" capability to manage air quality and air pollution data is limited for key pollutants. They and must improve air quality, said the report.
Dr. Schwela said many Asian cities can learn from Hong Kong and Tokyo, which are further along the road to achieving better air quality.
The book is the result of an international collaboration-led by the Stockholm Environment Institute at the University of York, the United Kingdom, and the Clean Air Initiative for Asian Cities-with the Korea Environment Institute and the United Nations Environment Program.
Cornie Huizenga, the book's co-author that heads the CAI-Asia Secretariat, says the report is the most comprehensive study of its kind to date.
Asia's growth in population, urbanization, motorization, and energy consumption remain the key challenges to efforts in countering air pollution. One particular challenge is that while vehicle emissions are being reduced, the volume of vehicles is rising rapidly.
The urban pollution report finds that air quality management has improved since the 1990s, and that concentrations of sulphur dioxide, a gas causing acid rain, have stabilized at a relatively low level within the international guidelines for human health protection from pollutants.
The use of fuel, with high sulphur content, in some countries however resulted in an increase in vehicles' emissions of nitrogen dioxide and fine particulate matter.
This situation has been the concern of all cities experiencing rapid motorization. If motoring use continues to rise then tropospheric ozone, a main constituent of petrochemical smog, will also increase.
While many major cities in Asia have some air quality management system, "sophistication and completeness is not always adequate", said the report as it recommended further actions to improve air quality in these cities. - Jasmin R. Uy