Re: Things went RIGHT for once
He didn't do it all by himself - he was on the teams that developed it.
While TMJ was on the team that determined that Tetraethyllead added to fuel prevented engine knocking of superior effectiveness and profitability to ethanol-blended fuels (it seemed tellurium worked well enough too, but that was discarded, as the slightest bit of tellurium pollution could be identifiable by a hard to eradicate smell), that wasn't ironic.
It wasn't ironic as it was well known from the start that it was a terrible idea to add lead to fuel and the company therefore did not mention lead in reports and advertising - calling it "Ethyl" instead.
Due to the small amount of TEL added per unit of fuel, short term lead exposure wasn't a problem - a lot of leaded fuel vapor could be inhaled once and nothing would happen (other than the impact of the toxicity of the fuel vapors) - but of course chronic exposure caused lead poisoning - which he suffered multiple times.
He later decided that he would help develop something harmless this time - and joined the team that proceeded to develop the first CFC's - which were non-toxic, non-flammable, non-explosive refrigerants (it was originally considered that such compounds would be toxic, but it was determined that the stability of the carbon–fluorine bonds resulted in non-toxicity).
It took 30 years after his death before it was widely known that R12 and other CFC's destroyed atmospheric ozone.
Ironically he killed themselves in the end via accidental strangulation by the elaborate system of (intended to be harmless) ropes and pulleys he devised to pull his severely disabled body out of bed.
https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.?useskin=monobook#Career