One of my first memories of watching TV during the early 1950s was ads promoting leaded gasoline for reducing engine knock. Little did I suspect the strange history of that gas. By the beginning of World War I, it became clear that the internal combustion automobile was edging out its rival steam cars and electric cars. Shortly afterwards, Thomas Midgley began researching how to remove the knocking “ping” sound from gasoline-powered cars.
Midgley devoted no fewer than six years of his life searching for a fuel additive that would have a “no-knock” effect. He found that corn alcohol would be too expensive. Benzene would also be effective, but it would be impossible to manufacture enough. Both oxygen and chlorine increased knock. Aniline, selenium oxychloride and tellerium worked, but produced an awful smell. Examining one element after another in a periodic table of the time, he finally found a gasoline additive: tetraethyl lead. Since poisonous effects of lead were well known, the product was labeled “ethyl gasoline.”
Multiple states banned sale of ethyl gasoline, prompting a retort from Midgley that car exhaust contained far too little lead to cause concern. A vice-president of a new gas company proclaimed that leaded motor fuel was a “gift of God” as Midgley told his partner that they could make 3¢ from each gallon of leaded gasoline in the 20% of the market they could corner. During the next few decades, leaded gasoline…