It's like mist but with pollutants (4)
I believe the answer is:
haze
(Other definitions for haze that I've seen before include "Mistiness" , "Slight atmospheric mist" , "Vapour" , "Film" , "'Mist, light fog (4)'" .)
I believe the answer is:
haze
(Other definitions for haze that I've seen before include "Mistiness" , "Slight atmospheric mist" , "Vapour" , "Film" , "'Mist, light fog (4)'" .)