Yes, but the avgas lead situation is primarily a problem for the people behind/under the aircraft, not inside the aircraft.

You still have to fill it up by touching and breathing in the fumes while pumping it into the tank, so not exactly, but you're right that it does affect others as well.

dunno about the evidence, but I kinda figured post-combustion lead is more atmospheric than pre-combustion lead. Elemental lead doesn't really absorb through the skin (and gas doesn't evaporate too well at low temperatures) as far as I know.

Lead added to fuel is in the form of an organic compound, so I'd expect the opposite effect. Obviously there's more distribution post combustion, but from a bio-availability standpoint spraying tetraethyl lead around in equivalent quantities would be a much more severe problem.

Naively (without looking at data for concentrations in various environments), I could buy that people regularly handling / being around leaded aviation fuel are worse off than those breathing the (dilute) exhaust products.

I realize this is an anecdote, not data, but after flying my own plane for 5 years and getting >500 hours of flight time, plus soldering off and on for 30 years with leaded solder, my lead levels were fine at my last physical. I don’t drink avgas or anything, but don’t take precautions other than attempting to avoid getting it on bare skin.

We got one of them fancy lads what drinks the jet A, boys. Thinks the 100LL ain’t good enough, no doubt!

:)

From first look, yes, and for more or less modern engines, which really don't need lead.

But for planes, normal age more than 20 years, even exist workhorses with 70 years.

They have very old engine technologies, some literally spread gas on ground (use lead in it to lubricate valves, which are outside, like on old star engines). So even when you walking where such plane was, you will gather some lead.

Guessing parent was referring to the practice of heating BPA-laden paper in the near vicinity of commercial food-prep

Yes the problem is recertification. This is why GA also still uses engines developed in the 50s with associated tech.

We are losing out on so much.

We are yes... Turbodiesel seems to be the answer even though a rebuild is not possible so they need a replacement very often :( On the other hand the unleaded gas engines like Rotax seem to be super reliable in the ultralight category, they are just not certified for real GA. I would imagine that slightly scaled up they could be a real workhorse.

Or perhaps a really small turboprop. I've seen really tiny jets so why not stick a prop on it (because jets are too inefficient at low altitudes). Might help with noise too.

There's so much innovation we could be taking advantage of :'( But we're still using engines designed in the 50s with lead (replacement) and manual choke/mixture that cars have deprecated 30 years ago.