H23,
Life is about compromise. Yes the pollution is a negative (he says while his kids are swimming in the back garden, on a stunning day with incredible viz) but have you ever lived in a safer place than HKG?
Go back to the UK and enjoy the clean air and miserable weather. Just watch out when the terrorists decide to blow up the Underground! Unlikely? Perhaps, but you never know.
It's the old two buckets story again. When the sh1t one fills up I'll leave (pollution falls in this bucket if you were in doubt) but at the moment the family is enjoying it too much to do so.
AND no I am not a new joiner S/O. Been here since before the last pay rise!
W2