The form of the metal matters. The elemental lead in leaded solder is not nearly as harmful as the lead in various compounds like tetraethyl lead anti-knock additive for gasoline, or the compounds used in leaded paint.

About mercury, consider that it's still widely used in dental amalgam.

FDA article on amalgam: http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedur...

> A lot more brave than I am, even if it is lead free.

Nobody who knows what they are doing works with lead-free solder for manual rework or repair. It needs a higher temperature, flows poorly, and produces an ugly matte surface, upon cooling, that looks like a cold solder joint even when the joint is actually good.

I can almost guarantee you that Woz is using nothing but 60/40 Sn/Pb in that shot. :)