Are McDonald's and Burger King toys from the 80's and 90's painted with lead based paint?

I seriously doubt it as they are food handlers, so the requirements are more stringent.
As leaded paint was generally banned in the late 70's then that would seal the case.
Also they would have to comply with the local toy regulations as well, so that would also rule out leaded paint usage.

Yes there had some issues, there was even recalls as late as 2007 with toys that had lead paint. They also had a major recall of drinking glasses with cadmium.

Other major companies effected often are Walmart and Oriental trading companies among many others.

Even in this last year 2011 places like Target and Build-a-bear