Is lead toxic?

Is lead toxic? Jean Opsomer has already pointed out the reference 
Toxicology: the Basic Science of Poisons, by Casarett and Doull (1991).
Let me give a more personal opinion.

Following my engineering degree, I worked for almost four years at 
North America's largest lead-zinc mine, Brunswick Mining and Smelting
in New Brunswick Canada. I worked in the concentrator which produces 
the lead and zinc concentrate. The zinc concentrate was sold to other
consumers, but the lead concentrate was smelted into metallic lead 
in the smelter. Lead contamination was taken *very* seriously, with
blood lead tests yearly. In the concentrator, the welders apparently
suffered from the highest blood lead levels. This was because they
were exposed to more lead vapour while welding/cutting (lead concentrate
was everywhere and they couldn't cut without burning some of it).
In my time there, I met one long time smelter employee that suffered  
from lead poisoning. I suppose his symptoms would be called neurological
in that he was not "all there".

This is moving way, way off the topic of aquatic plants and flourescent
lamps and ballasts ;-) Suffice it to say, lead is toxic.

Ian Philips
ianphil at bnr_ca