Tetraethyllead (commonly styled
tetraethyl lead), abbreviated
TEL, is an
organolead compound with the formula
Pb(
C2H5)4. It is a
fuel additive, first being mixed with
gasoline beginning in the 1920s as a patented
octane rating booster that allowed
engine compression to be raised substantially. This in turn increased vehicle performance and fuel economy.
[3][4] TEL was first
synthesised by German chemist
Carl Jacob Löwig in 1853. American
chemical engineer Thomas Midgley, who was working for
General Motors, was the first to discover its effectiveness as an
antiknock agent in 1921, after spending several years attempting to find an
additive that was both highly effective and inexpensive.
Concerns were later raised over the toxic effects of
lead, especially on children.
[5] On cars not designed to operate on leaded gasoline, lead and lead oxides coat the catalyst in
catalytic converters, rendering them ineffective, and can sometimes foul
spark plugs.
[6] Starting in the 1970s, many countries began phasing out TEL in automotive fuel. In 2011 a study, backed by the United Nations, estimated that the removal of TEL had resulted in $2.4 trillion in annual benefits, and 1.2 million fewer premature deaths.
[7]