A former Families South Australia worker who blew the whistle on one of the state's worst paedophiles is suing the state of South Australia for damages. 

The woman, who can't be named, is seeking compensation for emotional distress and financial losses suffered after her concerns were ignored by superiors within the government department.

She claims she was "intimidated" by colleagues and superiors after warning them of the allegations against the now-convicted paedophile McCoole, who is serving a 35-year prison sentence for sexually abusing young children and babies in state care.