Recent government figures show that air quality in Hong Kong has improved, but levels of pollution are still dangerously high and will only get worse due to too much traffic, an environmental group has warned.
The Clean Air Network has found air pollution near roads to be worst in the western parts of Hong Kong. It also found that with the neighbourhoods most affected were the poorest, most socially deprived, densely populated and clogged with traffic.
Then network believes the government needs to create better transport policies to reduce the health risks caused by traffic pollution.
“Major air pollutants may be decreasing in concentration but the public’s health is still not sufficiently protected,” said community relations manager Loong Tsz-wai. “The government must target the crux of the problem and that is high traffic density.”
In the first half of this year, average nitrogen dioxide (NO2) concentrations at monitoring stations on the city’s eastern side, including Tseung Kwan O, Tai Po and in Eastern district, averaged about 39 micrograms per cubic metre of air. This was within both Hong Kong’s own ‘safe’ limits and the World Health Organisation limit of 40mcg.
In western Hong Kong however, which includes districts such as Sham Shui Po, Central and Western and Tung Chung, the average concentration was a much higher 50mcg.
The group also tried to measure pollution in West Kowloon districts around the local monitoring stations and found that levels of roadside pollution were actually much higher than official readings. At five primary schools located near an expressway, NO2 readings ranged from 76 to 125mcg, far above WHO standards.
Citing previous academic studies, Loong said there was a direct link between a district’s population, household income, traffic density and air quality. The more populated and less well-off areas had greater traffic and thus were more exposed to unhealthy air.
“Most districts in western parts of the territory which have lower household incomes and denser populations were found to have worse air quality,” he said, adding that Sham Shui Po, Kwai Tsing and Kwun Tong were the districts in most need of help.
The group’s officer Winnie Tse Wing-lam told Young Post on Friday that geographical factors also contributed to the worse air quality of these areas. “These areas are more distant from the sea and hills. Such locations often have less rain, so there is nothing to blow away the pollutants. But there are other factors too. For example, the underprivileged are unable to buy air refreshers,” she said.
According to the group, a district with high traffic density alone increased the excess risk of mortality from respiratory diseases by 59 per cent. Mortality rates by respiratory and circulatory diseases in such districts were found to be up to 2 per cent higher than in other districts.
Loong admitted that the Environment Bureau had been doing what it could within its policy ambit to curb pollutants, but he urged the new administration to start looking at air pollution from a public health perspective and tackling it with better traffic management policies.
Tse also said the Transport and Housing Bureau should set targets for traffic congestion or roadside air quality. The government, she added, should also reduce the number of private vehicles, which mostly contributed to the high roadside pollution index.