Stuck on a crossword? Learn the surprising cause of low visibility in cities!

Stuck on a crossword? Learn the surprising cause of low visibility in cities! - SMOG
Cause of low visibility in some cities

Type of air pollution –
Haze caused by emissions –
Urban pollution problem –
Blend of smoke and fog –
Causes respiratory issues –
Results from burning fossil fuels –
Environmental concern in many cities –
Yellowish brown atmospheric condition –

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