Have a look at page 4 of The Standard today (Monday 19th Nov). American investment guru Jim Rogers states that the high level of air pollution has forced him to go to Singapore. "Expatriates in Hong Kong...have repeatedly called on the government to make cleaner air a priority..." "Air pollution costs the city about HK$ 21.2 billion a year in hospital admissions..."
Looking out the window, it must be about 4000m if you're lucky. You can taste the air.
BB