[pas]

it's not how that works. you need to look at the counterfactuals too.

TEL decreased knocking, which decreased incomplete combustion, which decreased pollution a lot.

lead pollution from gasoline was about 30% of all lead pollution.

it's great that people recognized how harmful lead pollution is and coordinated action was taken.

for CFCs it allowed the development of fridges that use non-hazardous working fluid. previous ones used propane for example, folks kept their fridges on the porch because there were some that exploded.

from this article/essay (I'm not endorsing the main message, but the need for nuance and cost-benefit analysis is correct IMHO)

https://americanaffairsjournal.org/2023/11/technological-sta...

[mort96]

Surely the counterfactual isn’t “what if we did nothing to reduce knocking”, but rather “what if we used any of the other substances which were known to reduce knocking and known to be safer, such as ethanol”?

[pas]

Yes, and also "if we cared more about proving health safety", and unfortunately it seems - looking at aviation where TEL is just getting phased out - mostly we don't care enough.

[sokoloff]

R290 (highly pure propane) is still used pretty widely as a refrigerant with relatively low environmental impact.