Drops environmentally unfriendly car India produced (4,4)
I believe the answer is:
acid rain
'drops environmentally unfriendly' is the definition.
(drops of rain which harm the environment)
'car india produced' is the wordplay.
'produced' indicates anagramming the letters.
'car'+'india'='carindia'
'carindia' with letters rearranged gives 'ACID-RAIN'.
(Other definitions for acid rain that I've seen before include "Damaging precipitation" , "Harmful atmospheric fallout" , "Pollution from the sky" , "it's bad for the environment" , "Polluted precipitation" .)