SCMP – Updated on Dec 19, 2008
On Monday, the air pollution index (API) on the Environmental Protection Department website for the previous 24 hours ranged from 84 to 88; that was bad enough. But a study of the previous 24-hour pollutant concentrations reveals that, in Causeway Bay, respirable suspended particulate (RSPs) levels were 150 at 3pm and 168 at 8pm on Sunday; then 115 at 6am and 154 at 2pm on Monday.
The corresponding levels of nitrogen dioxide (NO2) a known respiratory poison, were 168, 140, 83 and 143, respectively. In Yuen Long at 2pm, RSPs were a staggering 256: in Mong Kok, NO2 was 240. Nowhere was the API registering above 100.
Three points are to be made about this. First, the API bears little or no relationship to the actual daily pollutant concentrations which are dangerously high and damage the health of all Hong Kong citizens more than a downturn in the economy. The persistent use of an outdated API is literally a smokescreen by government criminally negligent in its duty of care for the public’s health.
Second, the cyclic pattern shows a high correlation with urban activity, indicating that locally generated – not imported – pollution is to blame, particularly for high NO2 levels.
Third, despite the usual Observatory explanation of a lack of wind, the cause of the problem is clearly a lack of will. The population remains misinformed about the perilous state of our air and the damage it is doing to people’s health. It is about time the government was taken to task about its failure to face up to the true state of Hong Kong’s air and not just in the pages of the South China Morning Post. Would the undersecretary for environment care to comment?
Richard Fielding, professor, school of public health, University of Hong Kong