Hong Kong residents are exposed to air pollution that could be much worse than government data suggests, according to researchers from City University and Civic Exchange.
Readings they obtained from volunteers who carried mobile sensors while they went about their day to day activities showed their exposure was sometimes much higher than data from fixed government monitoring stations nearby.
Data collected from 73 people, who carried the lunchbox-sized sensors over a six-month period, differed greatly from the government's pollution figures.
The volunteers' sensors reported on their exposure to PM2.5 – a fine particle produced largely by vehicles. Their exposure on roadsides was generally much higher than readings from the nearest government air monitoring station.
But surprisingly, exposure to pollutants was also high when the volunteers were at home.
Simon Ng, a Civic Exchange fellow and co-author of the report, said the government should do more to educate the public about indoor air pollutants.
The researchers say the government also needs to tighten its own air quality objectives, which are still looser than World Health Organisation guidelines.