The Deadly Burden of Hong Kong's Poor Air Quality

Air pollution in Hong Kong is an under-appreciated health and environmental crisis, placing an enormous burden on the health of residents. Globally, the WHO estimates that ambient (i.e. outdoor) air pollution causes the premature death of 4.2 million people annually, with the greatest burden in South-East Asia and the Western Pacific regions.

This mortality is due to exposure to small particulate matter of 2.5 microns or less in diameter (PM2.5), which cause cardiovascular and respiratory disease, and cancers - It is estimated that approximately 3% of cardiopulmonary and 5% of lung cancer deaths are attributable to particulate pollution globally.

Hong Kong PM2.5 levels regularly exceed WHO limits

The WHO annual average limit for PM2.5 fine particulate pollution is 15 μg/m³:

• In 2019, every one of the 16 pollution monitoring stations that track this data in Hong Kong exceeded this limit.

The WHO daily average limit for PM2.5 fine particulate pollution is 25 μg/m³. This limit may be exceeded a maximum of 3 days per year:

• In 2019, the Central/Western monitoring station exceeded this level on 110 days.

No safe level

It's worth noting that these limits do not represent safe levels - no safe level has been identified, below which negative health outcomes do not occur.

For example a Japanese study showed that over a 2-year period where the average PM2.5 level was only 12μg/m³, each 10μg/m³ increase in levels resulted in a 3-4% increase in cardiac arrests (heart attacks).

Embee recommends monitoring levels in your location and timing outdoor activities to minimize exposure when levels are excessive. Current levels and recommendations for HK districts and primary/secondary schools can be monitored here:

What are the health implications for Hong Kong residents?

Hong Kong's poor air quality places a heavy health burden on residents:

Outdoor air pollution kills an estimated 6300 people per year in Hong Kong, or an average of 17 per day. School of Public Health and Primary Care, CUHK

Deaths primarily result from heart disease, stroke, other cardiovascular and respiratory diseases, and cancer.

“[There is a] strong association between high pollution incidents and both hospital admissions and premature deaths for respiratory and cardiovascular diseases”. Center for Health Protection, HKSAR

Air pollution in pregnancy has been linked to premature birth, stillbirth, impaired fetal growth and birth abnormalities including abnormal heart valves and cleft palate.

Where does Hong Kong’s air pollution come from?

• Contrary to popular belief, most of Hong Kong's air pollution is generated locally.

• Shipping is the biggest contributor, with power stations and diesel vehicles and construction machinery also substantial sources.
• Hong Kong allows container ships to burn cheap and dirty 0.5% sulfur content fuel while in Hong Kong waters and at berth.
  • This is 5 times the 0.1% limit in Europe, North America, South Korea, and China’s Yangtze / Xi Jiang river areas and Hainan Coastal ECA.
• At the roadside, diesel vehicles and construction machinery are the primary source.

This is easily seen on Embee's air quality monitoring pages, where local sources result in poorer air quality nearby:

Below are additional links to Hong Kong air pollution advocacy/charity organisations, related government websites, pollution complaint forms, as well as more detailed information on individual pollutants.