You may want to do a search of Zinc (71 hits), Fume Fever (15 hits), etc on IForgeIron. There is much more information presented, and discussed on the subject, which includes many off site references such AWS (American Welding Society) health and fact sheets, medical papers, etc.
Zinc if not the only heavy metals (or the worst heavy metal) a blacksmith will encounter. YOU must read the material posted on IFI (and other sites) to gather the information and knowledge to stay safe.
PPW (Jim Wilson) was a member of IForgeIron. HE was the first person to alert me to the dangers of heavy metal poisoning, fume fever, etc.