You're not breathing lead vapor. You're breathing flux vapor, which is probably not optimal either.
https://www.quora.com/Can-I-get-lead-poisoning-from-inhaling...
https://www.quora.com/Can-I-get-lead-poisoning-from-inhaling...
The primary means of exposure in a lab setting is through ingestion of particulate matter by getting it on your food or clothes -> mouth
Here's an environmental safety article from MIT. It mentions lead oxide fumes from soldering. What do I know other than the required lab safety training.
Based on standard soldering iron temperatures of 620°F-700°F and the melting point of lead (621°F), it is unlikely that lead fume will be generated during electronic soldering, unless the solder is heated to lead’s vaporization temperature of 3182°F.
"During the soldering process in the form of lead filler metals, lead oxide
fumes are formed and excessive exposure to lead oxide fumes can result in
lead poisoning."
It's right there and easy to read.