> cut back on my smoking
You know that is FAR worse than hobby soldering.
Folks older than you grew up with lead. Nevermind soldered copper pipes (very thin lead-edge exposed to the water); I found all-lead pipes in my last house. The toilet dump-pipe was of course not a problem, except I did touch it to re-seal it (and learn the true meaning of "lead-pipe cinch"). But there was also a lead water MAIN, abandoned, but clearly used for many years.
Lead paint is the best stuff for trim. Painters would buy the raw stuff and pound it into linseed oils for paint, then when it flaked off toddlers would eat the sweet flakes.
Oh, yeah, lead soldiers and charm-bracelets. Toy cars. Fishing weights. Flashing. Downspouts. Sash weights. But you really don't get much exposure from weathered lead through skin.
And all the ethyl tailpipe fumes. And the toxicity of tetraethyl lead was known in the 1920s, when they started putting it in gasoline. There seems to be a gradual process: early ethyl was maybe 0.2 proof and Esso could find reputable doctors to agree that's not much (in a civilization largely based on lead). Over the decades that crept past 1.0 proof. I wonder how much lead was in Sunoco 104? And there was 120/140 Octane stuff for WWII fighter planes... that's gotta be over 4.0 proof, though not many people hung around it.
Did all that lead hurt our memories? I forget. But I suspect many of us fried far more brain cells with bad drugs (booze is popular, street LSD could be nasty) than all the lead we handled, even inhaled.
Rosin is pine sap. Same as the snot on your car when you park under an old pine tree. Gash a pine tree, it bleeds, distill the sap, you get turpentine and pine-tar, both essential for old-skool wood ship building. In between the liquid and the tar, you get rosin.
Been boiling pine sap for hundreds of years. Turpentine is still sold everywhere. People used to drink it as a remedy. It's probably no good for you, but seems to do no harm.
The toxicity of rosin has never really been studied, _because_ it has been so widely used for so many centuries with so little problem.
There IS a common allergy to rosin smoke. You'll know, it comes on quick. Workers who had to quit the soldering occupation seem to recover soon after they stop inhaling it every day.