Hong Kong feared to witness major reduction in roadside pollution

Pollution causes thousands of premature deaths annually.

Hong Kong should see the reduction within the next six months as the government clamps down on a long-running problem that also hurts the city's business competitiveness. A new scheme will revoke the licenses of taxis and mini-buses that do not comply with tougher maintenance standards.

These 20,000 vehicles are the culprits for increasing levels of toxic nitrogen dioxide. Since 2008, NO2 has increased by some 20% even as levels of other pollutants declined.

The government said the reason was that while these vehicles had upgraded to cleaner LPG fuel, they fail to regularly change their catalytic converters that convert harmful emissions. These need to be changed every 18 months.