Those old wrist watches that glowed in the dark, yeah, they killed a whole bunch of old ladies who worked in the factory. Most of the old ladies woud lick the bristles to make a fine tip for painting arms and numbers. The ladies that didn't die lost most of their jaw.
Most things radioactive have half-lifes on the order of hundreds of thousands of years, so if they were radioactive in the 70's they are still radioactive now.
My advice, don't lick your old brush. :)
Lucas