I feel a new hub claim on the horizon - one they can actually claim that isn't ##
this is pretty serious, high risk to health
when I lived in the UK surface dust on table tops and furnature was fibre from carpets etc and took months to become noticeable to any degree, while here a thick layer of dust can build up in a couple of weeks especially if you have open windows, run a finger through that stuff and it is black like soot same on the tiled floor - don't mop it for a week and your feet end up black, this is not household dust like we get back home.
and my pc air filters and cooling fans need cleaning every few weeks, I wonder how are lungs are doing, this is pretty serious and needs urgent attention
I suspect there are many reasons for this - poorly laid concrete with lack of binding agent - removal of catalyst from vehicles to achieve more power (I think extremely common) in diesel vehicles - old trucks/buses either don't have catalytic converters or new ones were they are never fitted