On Thursday's 'Steph's Packed Lunch' presenter Steph McGovern broke down in tears after hearing how former footballer Chris Kamara was subjected to racism in his footballing days because of programmes like 'Love Thy Neighbour' and the character Alf Garnett:
https://m.youtube.com/watch?v=jbUu-ZuA8PU
Russell Kane had to take over to go to an early break whilst she composed herself.
The only other time i've come across someone breaking down with emotion was after seeing the footage of the Hindenburg disaster where the reporter broke down whilst reporting the tragedy of the airship bursting into flames mid air with people on it, but there must have been other occasions.