dont really want to find out the hard way about lead poisoning and how much it takes to KO me, think your more at danger when actually soldering because it is natural to lean in close when working with these small areas of circuit and you cant help but inhale it and the thing about lead and other heavy metals is they have an accumulative build up, so you dont get rid of them and they just keep building up. I'm guessing alot of the folk that come on here are young (ish!) so i'm sure they would like to preserve their health and good on tin solder for mentioning it and trying to save us going through the same pain he has.
But yeah really important to not eat, smoke where you are soldering and lots of light is a must, get a good mask also, i use one that is made for airbrushing and it is ok to work with it on and it saves having to deal with the constant wisps of smoke. I use leaded solder, not sure what others are using, dunno if there is the same need for non leaded (yuk) but its crap anyway. Solder fans are ok but you have to be close for them to be affective, have to say though its amazing the shit that builds up on the carbon filter of a solder fan makes you realise what could be going in your lungs, it scared me into using the airbrush mask.