If there was anything to worry about, NOBODY would use or sell them, I'm not saying to not worry, but just dont melt the insulation on wire where possible. 1. It don't smell too nice. 2. It gives can you a headache.
Soldering is worse with the lead, as I understand, stuff like orange juice helps to clear lead out of your system quicker, but it naturally clears out anyway.
Steak sauce last I heard was carcinegenic, so is woostershire.
I remember you saying something about having a reaction to some wood, I'd worry more about that than some wire.
But then I'd worry more about tapeworm from too much rare meat, to which I doubt anybody does.
Edit : I apoligize beforehand if this is going a bit far, I don't mean to offend you in anyway, but you seem to me to be a hypochondriac. Just chill out, people make a living working with this stuff, and you don't exactly hear about steve the electrician dying of too much cable do you? Maybe Shane or Kane, but no Steve.