leaded gasoline

chemical compound

Also known as: ethyl gasoline

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Last updated

June 30, 2026

Quick Summary

Leaded gasoline is a fuel that contained tetraethyl lead (TEL), an organometallic compound with toxic lead. TEL was primarily used as an antiknock agent in gasoline to improve engine performance by preventing premature fuel combustion, known as engine knock. The compound, with the chemical formula C₈H₂₀Pb, was manufactured by reacting a lead-sodium alloy with ethyl chloride.

Beginning in the 1970s, leaded gasoline was phased out globally due to its contribution to lead poisoning and its interference with pollution-control devices in automobiles. Despite initial assurances of safety, concerns about lead's impact on public health, particularly on children's development, led to its eventual ban in many countries. The U.S. Environmental Protection Agency announced the phase-out in 1972, primarily because lead interfered with catalytic converters. By 1995, leaded gasoline was no longer available for passenger cars in the United States, and similar bans followed in Canada and the European Union.

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petroleum refining
Octane rating
The advent of leaded, or ethyl, gasoline led to the manufacture of high-octane fuels and became universally employed throughout the world after World War II. However, beginning in 1975, environmental legislation began to restrict the use of lead additives in automotive gasoline. It is now banned in the…
Read More
The advent of leaded, or ethyl, gasoline led to the manufacture of high-octane fuels and became universally employed throughout the world after World War II. However, beginning in 1975, environmental legislation began to restrict the use of lead additives in automotive gasoline. It is now banned in the…
Read More

hydrosphere
Ice
…1970s regarding the use of leaded gasoline has led to a fall in lead concentrations in ice laid down since that time.) Also, atmospheric carbon dioxide and methane concentrations, which have increased significantly during the past century because of anthropogenic activities, are faithfully recorded in ice bubbles of the thick…
Read More
…1970s regarding the use of leaded gasoline has led to a fall in lead concentrations in ice laid down since that time.) Also, atmospheric carbon dioxide and methane concentrations, which have increased significantly during the past century because of anthropogenic activities, are faithfully recorded in ice bubbles of the thick…
Read More

tetraethyl lead
Beginning in the 1970s, “leaded gasoline” was phased out, first in the United States and then in Europe and around the world, on account of its contribution to lead poisoning and its interference with pollution-control devices installed in automobiles.
Read More
Beginning in the 1970s, “leaded gasoline” was phased out, first in the United States and then in Europe and around the world, on account of its contribution to lead poisoning and its interference with pollution-control devices installed in automobiles.
Read More