The history of ethanol in gas is quiet old. Per https://www.eia.gov/kids/history-of-energy/timelines/ethanol.php https://www.eia.gov/kids/history-of-energy/tim

The history of ethanol in gas is quiet old. Per https://www.eia.gov/kids/history-of-energy/timelines/ethanol.php https://www.eia.gov/kids/history-of-energy/timelines/ethanol... It looks like it usage of ethanol as an additive started increasing around the same time lead was being phased out.