The Hong Kong Environmental Protection Department (EPD) and the Department of Environmental Protection of Guangdong Province released the 2011 Pearl River Delta Regional Air Quality Report today. The Report shows continuous improvement of air quality in the Pearl River Delta (PRD) area, indicating that the joint efforts of both Governments are having an effect.  In contrast, Hong Kong’s own air quality has not shown the same degree of improvement. Based on data from the EPD’s monitoring stations, Clean Air Network (CAN) found that Hong Kong’s air quality worsened last year, particularly levels of roadside nitrogen dioxide (NO2), which were the worst they have ever been since monitoring began. This demonstrates that Hong Kong’s deteriorating air quality is the fault of local sources, and not the PRD, which, as the Report states, has better air quality than before.

The Report shows that, last year, the annual average NO2 concentration in the PRD region decreased by 13%, compared to concentration levels in 2006; however, CAN found that NO2 levels in Hong Kong increased by 3% at general stations and 28% at roadside stations from 2006 to 2011. In fact, last year, roadside NO2 levels reached record highs (123µg/m3).  In addition, the PRD region’s recorded levels of SO2 and PM10 last year were 49% and 14% lower, respectively, compared to levels recorded in 2006. In comparison, the decrease for the same two pollutants were only 40% and 10% for Hong Kong.

The General Manager of CAN, Helen Choy, says, “The continuing improvement of regional air quality highlights the fact that most of Hong Kong’s air pollution comes from local sources. Apart from collaborating with the Guangdong government to reduce regional air pollution, the Hong Kong Government should put more effort into improving local air quality, particularly with regards to speeding up the pace to phase out old and dirty buses and commercial diesel vehicles, which are the primary sources of roadside pollution in our city.”

Table 1. Annual average concentration of regional air pollution (µg/ m3)

Table 2. Annual average concentration of Hong Kong air pollution (µg/ m³)