Pollution in Shenzhen

Pollution in Shenzhen that is located at the South China Sea is considered to be moderate. At least, in comparison to the inland areas of China.
But sometimes it gets worse. This is the view from our 28th floor balcony in the Futian District of Shenzhen - on a bright day and on a "not so bright" day.

I must admit I haven't experienced anything similar yet, despite I have lived in a city with population of 5 million for many years.

Sometimes one has a feeling that there is literally no oxygen in the air. I wonder how does it feel in the inland of China?

So how bad should it get before something starts changing? I mean, how deep should be the damage for environment and health of ordinary citizens before environmental standards are effectively implemented?

Modern City Hall of Shenzhen