District exceeded the WHO’s limit on the concentration of small particulates in the air on 227 days of 2016
Causeway Bay, on Hong Kong Island, had the poorest air in the city in 2016, followed by Tuen Mun in the New Territories West and Mong Kok in Kowloon, according to chief of the city’s Environment Bureau, citing from analyses by the Environmental Protection Department.
Secretary for the Environment Wong Kam-sing made a written reply to the Legislative Council on Wednesday regarding concern over high-level air pollution in Hong Kong.
The World Health Organization’s guidelines state that the concentration of small particulates PM2.5 over a 24-hour period should not exceed 25 micrograms per cubic metre.
In 2016, Causeway Bay exceeded the limit on 227 days of the year, while for Tuen Mun and Mong Kok the numbers were 173 days and 171 days respectively. Other locations in Hong Kong monitored by the government averaged 100 days.
Pollution from the Pearl River Delta in Guangdong Province and tropical cyclones are often blamed for Hong Kong’s poor air quality.
Over 80% of high pollution days were said to be caused by the downdraught effect of tropical cyclones, which results in the accumulation of ozone and fine suspended particulates in the Pearl River Delta. Wong explained that the pollutants are then brought to the city by westerly or northwesterly winds.