SCIENTISTS say petrol might be a worse polluter than diesel and have called the Government's planned swap in fuel for taxis and minibuses 'illogical'.
Although diesel was the culprit for the smoke and dust that caused breathing problems, the scientists said that petrol produced more carbon dioxide and hydrocarbons which could add to global warming and cause smog.
That was a more dangerous hazard than dust, said Hong Kong University researcher and Combustion Institute member Ron Tse Siu-man.
Hong Kong University mechanical engineer Dennis Leung Yiu-cheong said petrol gave out much more smog-producing carbon monoxide than diesel and contained more of the highly carcinogenic substance benzene.
But diesels run at low speed in traffic jams produced about twice as much nitrogen oxides as petrol, he said.
Hong Kong's air quality objectives regularly fail because of high nitrogen dioxide and carbon monoxide emissions, according to Environmental Protection Department figures.
