A HISTORY OF GASOLINE ADDITIVES
As one example, alkylleads were found to alleviate the "knocking" prevalent in automobile engines. Despite the known toxicity of lead, tetraethyllead was blended with gasolines beginning in 1923. Some 50 years hence, and after substantial pollution of the environment by lead, alkyllead additives were phased out in a process that required another 15-20 years.
Other notable additives, such as Mn compounds (MMT) and MTBE, have been used to enhance gasoline octane ratings or comply with evolving emission standards. Now, scientists employ our historical knowledge of gasoline additives to answer significant questions which arise during environmental remediation.