The slurs being broadcast are really brutal (8)
I believe the answer is:
ruthless
'really brutal' is the definition.
'the slurs being broadcast' is the wordplay.
'being broadcast' indicates an anagram.
'the'+'slurs'='theslurs'
'theslurs' with letters rearranged gives 'RUTHLESS'.
'are' is the link.
(Other definitions for ruthless that I've seen before include "Brutal" , "Without pity or compassion" , "Without pity, merciless" , "Unmerciful" , "devoid of compassion" .)