New research out of the University of Hong Kong suggests that the city's poorest are exposed to greater levels of air pollution.
In a paper recently published in the Environmental Science and Policy journal, researchers from the HKU-Cambridge Clean Energy and Environmental Research Platform (CEERP) said there was a statistically significant, positive relationship between Hong Kong's ambient PM 2.5 concentration and its Social Deprivation Index.
Professor Victor Li, director of HKU-Cambridge CEERP, said previous research into this area had been hindered by sparse air pollution data with only 16 government-run pollution monitoring stations dotted around the city.
They created a model that used existing government data – pollution monitors, traffic and meteorology information, and data on urban morphology – to estimate air pollution at 110,000 points around the city. This allowed them to identify the areas with the highest levels of PM2.5 concentrations.
Li explained that they chose to focus on PM 2.5 (particulate matter less than 2.5 microns wide) because it has been medically proven to be among the pollutants that cause the most damage to human health.
They then compared the pollution information to indicators of social deprivation from the 2011 Population Census.
Areas in Yuen Long, Kwun Tong, Sham Shui Po and Kwun Tong were identified as being places with high monthly concentrations of PM 2.5 and also scored highly on the social deprivation index.
Li said their study highlighted the need for more integrated, location-based environmental policies.
"Right now, we have a lot of new MTR stations, and as a result we are re-routing some of the bus routes. So in the planning of re-routing bus routes, the government should look into the air pollution and SDI levels of different districts," he said.
"For example, if there's already a highly polluted area, why would you want to route the bus route there?"
Li said pedestrianisation of densely populated areas could be another solution, and electronic road pricing could be used depending on the air pollution levels at different times of the day.