The Inventor Who Accidentally Poisoned the Entire Planet Twice

In the 1920s, Thomas Midgley Jr. developed tetraethyl lead as a gasoline additive to prevent engine knocking. To prove it was safe, he washed his hands in the stuff and inhaled it for 60 seconds at a press conference. Decades later, the lead from his invention was found in ice cores in Antarctica and caused measurable IQ drops in children worldwide. Not content with one disaster, Midgley then invented CFCs for refrigeration in 1930, which later turned out to destroy the ozone layer and act as super greenhouse gases. He is the only person in history to single-handedly threaten the entire planet twice.