and still sprayed all around the surrounding land at almost every airport in the USA and worldwide from prop aircraft exhaust despite knowing ANY amount is toxic and irreversible for 30+ years
* https://www.nbcnews.com/business/business-news/leaded-gas-wa...
You say that in the past tense... But pretty much every propeller plane worldwide still uses the stuff...
Very true that only recently, a lead-free substitute was available.
https://g100ul.com/