Tetraethyllead

Tetraethyllead (commonly styled tetraethyl lead), shortened to TEL, is a chemical compound with the formula (CH₃CH₂)₄Pb. They added this into petro-fuel. It was first mixed with gasoline in the 1920s. It increased vehicle performance and fuel economy by stopping engine knocking.^[1]^[2] TEL had been identified chemically in the mid-19th century. In recent years, this chemical has been linked to climate change and is highly toxic.^[3] It is no longer used in fuels because of this (most are now "unleaded").

Tetraethyllead Media

Sign on an antique gasoline pump advertising tetraethyllead by the Ethyl Corporation
Interactive map of the phase-out of leaded gasoline from 1972 to 2021. Click on the image to explore interactivity

References

↑ Tetra-Ethyl Lead as an Addition to Petrol. British Medical Journal 1 (3504) (3 March 1928). p. 366–7. doi:10.1136/bmj.1.3504.366.
↑ After Lead?. Popular Science (October 1987)Bonnier Corporation. p. 94.
↑ TETRAETHYL LEAD - National Library of Medicine HSDB Database.

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[BMJ1928-1] Tetra-Ethyl Lead as an Addition to Petrol. British Medical Journal 1 (3504) (3 March 1928). p. 366–7. doi:10.1136/bmj.1.3504.366.

[2] After Lead?. Popular Science (October 1987)Bonnier Corporation. p. 94.

[3] TETRAETHYL LEAD - National Library of Medicine HSDB Database.

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