Yes, roundabouts are safe for pedestrians.
In a typical roundabout, pedestrians walk on sidewalks around the roadway (not across the central island). If it is necessary for pedestrians to cross the roadway, they cross one direction of traffic at a time. Crossing distances are relatively short and traffic speeds are lower than at traditional intersections. The location of crosswalks at roundabouts are away from the main travel zone which provides motorists with more space and time to yield to pedestrians in the crosswalk.