Civic Exchange, a non-profit public policy think tank released a scientific research report today on fine particulate matter (PM2.5) in Hong Kong and Guangdong and ozone formation in Hong Kong and its surrounding area. Both PM2.5 and Ozone can have harmful impacts on human health.
The report found PM2.5 existed in the Pearl River Delta (PRD) region at projected averaged annual levels 2 to 5 times of the US National Ambient Air Quality Standard. Furthermore, the PM2.5 level obtained during the research period was over twice as high in Guangzhou compared to all sites monitored in Hong Kong. The 2-year Pilot Project also showed that the main chemical composition of PM2.5 was organic compound and sulphate (representing 24-35% and 21-32% of PM2.5 mass respectively). The main sources included emissions from vehicles, biomass and coal burning in Guangdong and meat cooking across the region.
Diesel emissions were relatively more prevalent in Hong Kong while leaded gasoline emissions were relatively higher in Guangdong. The Pilot Project concluded that PM2.5 levels in Hong Kong are influenced by both local and regional emissions, while Guangzhou is impacted more by local sources. PM2.5 has been proven internationally to be harmful to human health.
Based on data observed in the months October to December 2002, the Pilot Project also confirmed that high concentrations of ozone, a major gaseous pollutant in smog, exists in Hong Kong and its formation is dominated by man-made volatile organic compounds of which reactive aromatics (from fuel evaporation, use of paints and solvents, and vehicle exhaust) formed a large part. The Pilot Project also revealed that both local and regional emission sources can contribute to the ozone pollution in Hong Kong. Ozone at ground-level can cause damage to human health and the environment (trees and agriculture).
The Pilot Project measured ozone in Hong Kong over an autumn-winter period (Oct-Dec 2002) and PM2.5 in both Hong Kong and Guangdong during the months of October and December 2002, and March and June 2003 (five 24-hr samples per month). Monitoring stations included Conghua, Guangzhou, Zhongshan and Shenzhen in Guangdong Province and Tai O, Tung Chung, Tap Mun and Central and Western in Hong Kong.
The Pilot Project was the first non-government led cross-border initiative to improve regional air quality in the PRD and a key to its success lie in its broad stakeholder support base. The project model, which is based on an inclusive and transparent process in all aspects of planning, implementation and monitoring, provides a powerful example of the capacity of all sectors working together, including business, academia, civic organisations and the government, to tackle regional pollution problems. With scientists from Georgia Institute of Technology in the US and Peking University in Beijing and Shenzhen and local expertise from the University of Science and Technology and Polytechnic University in Hong Kong participating, the Pilot Project brought together a top international team of air quality experts, including an international Science Advisory Board. The Hong Kong Environmental Protection Department (EPD) was also integral to the study, contributing resources, data and expertise. The project was funded by Hong Kong Jockey Club Charities Trust, Castle Peak Power Co. Ltd., EPD and Shell.
The Pilot Project outlined a number of further steps which still need to be taken to provide critical data for both the Hong Kong and Guangdong authorities to move forward with a more comprehensive air pollution control strategy including:
(i) further analysis of the sulphate and organic sources and the specific industries which they are associated with, including investigation as to where and when biomass burning is taking place;
(ii) identify the exact sources of reactive aromatics that dominate ozone formation;
(iii) monitor PM2.5 and ozone across the region including the precursor gasses that contribute to their formation, and identify pollution ‘hot’ spots and trends; and
(iv) maintain and build air quality monitoring and analysis capacity in the region.
In view of the important findings of this project, both the Hong Kong and Guangdong governments should consider a review and establishment of PM2.5 standards and/or objectives and the inclusion of PM2.5 in both ongoing regional monitoring and emission reduction targets.