Lead doesn't have "fumes" or become airborne until it boils.Thats well above the temperature our lead pots can achieve.I think there is some particles that can release to the air at about 800 deg but i cant recall.lead poisoning is most common from handling it and not cleaning hands properly. The other common way was old poorly ventilated indoor shooting ranges.At our range in Charlotte there are about fifteen old codgers who are cast bullet specialists who shoot together every Wednesday, and more individually doing ongoing testing. BR pistols and rifles. They have a couple of matches monthly, and have won a number of national competitions and records, but ageing out of that now due to health issues. A number have been fighting cancer, and I wonder if lead fumes could be a contributor?
Lead poisoning is serious but not cancer causing.