Liz Heron – SCMP – Updated on Apr 27, 2008
Air pollution recorded at roadside stations was at very high levels for 10.69 per cent of the time in the first quarter of this year – up from 6.48 per cent in the same period last year.
Comparable readings in the medium range fell from 7.17 per cent to 4.29 per cent – with no readings in the low range for either quarter. High levels continued to prevail at more than 85 per cent of the time.
General stations also recorded higher pollution levels, with readings in the high range up from 51.77 per cent to 70.53 per cent of the period and very high readings up from 0.16 per cent to 0.37 per cent.
At very high readings of 101 to 200 on the air pollution index, people with heart or respiratory conditions are advised not to do strenuous outdoor exercise. The high range is from 51 to 100 and the medium range from 26 to 50.
The first quarter also saw hours of reduced visibility – an indicator of particulates or dust in the air – increase by 46.4 per cent to 448 at the Observatory in Tsim Sha Tsui, and at the airport by 11.6 per cent to 807, compared to the same period last year.
Edwin Lau Che-feng, director of Friends of the Earth Hong Kong, said the figures showed that “air pollution in Hong Kong is on a rising trend – and we are using an outdated standard of environmental monitoring. More stringent measures to control air pollution are needed”.
“To have a situation where the roadside API is high or very high for more than 95 per cent of the time should not be acceptable to any person in this wealthy, developed city.”
Amy Ng Yuk-man, of campaign group Clear the Air, said: “These figures show that the government has not yet done enough to reduce air pollution. “The government needs to do more in terms of the power plants, with transportation and also marine pollution.”
But a spokesman for the Environmental Protection Department said: “In the long run, air quality is primarily affected by emission sources. However, over a short period, say a few days to a few months, air quality can also be significantly affected by meteorological conditions apart from emissions.
“Scientifically, it is not appropriate to gauge air-quality change or the effectiveness of improvement measures by selecting air quality data in a few months and comparing them with the same months of other years.
“Our measurements show that the annual average air-pollution concentrations in 2007 are in general comparable to 2005 and 2006 and better than 2004.”