It's not absolutely a sure thing that there's any significant burden from aviation. Blood tests come up with a tiny, barely detectable difference near airports (well under 5% for those nearest the airport, and confounded: airports are correlated with low SES and therefore lead paint, etc, is also more prevalent). The most pessimistic estimates from first principles come up with 2-3% of the total population lead burden (more than an order of magnitude above what the blood tests imply, and the blood tests likely overstate the problem).
If you threw a few billion more at leaded paint remediation, I think you'd make much more of a difference. I think the aviation lead problem should get fixed, but because it's such a small part of the overall problem it makes sense to take a graduated approach instead of giving GA businesses the death penalty. Tax leaded aviation fuels, and use the proceeds to pay for leaded paint remediation.
Graduated approach ignores the decades that have ALREADY been provided as an exception to the lead fuel rules that apply everywhere else - it's already been graduated.
Start at 10% with a commitment to ratchet it up by 4% per year or something. That's enough to start an immediate reduction without destroying the industry.
If you're making choices about engine overhaul now for an overhaul that will last you 7-8 years of light use, fuel costing 40% more at the end of that overhaul will definitely get your attention.
> it's already been graduated.
Doing nothing for decades when it was impossible; and then doing nothing for a decade or two when transition became possible; and then pushing the industry off the cliff is not graduated.
Source please. All the studies I've read have barely detected higher levels of lead near airports, and are confounded. All the estimates from first principles estimate that it's a very small proportion of population lead exposure, too.
If you threw a few billion more at leaded paint remediation, I think you'd make much more of a difference. I think the aviation lead problem should get fixed, but because it's such a small part of the overall problem it makes sense to take a graduated approach instead of giving GA businesses the death penalty. Tax leaded aviation fuels, and use the proceeds to pay for leaded paint remediation.