Devastated Iran starts being bitter about pollution (4,4)
I believe the answer is:
acid rain
'pollution' is the definition.
(acid rain is a kind of pollution)
'devastated iran starts being bitter' is the wordplay.
I cannot really understand how this works, but
an anagram of 'iran' is 'rain' which is present in the answer.
'bitter' could be 'acid' (acid can mean bitter-tasting) and 'acid' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'about' acts as a link.
Can you help me to learn more?
(Other definitions for acid rain that I've seen before include "Destructive precipitation" , "Damaging precipitation" , "Form of pollution" , "Harmful atmospheric fallout" , "environmental disaster" .)