Tetraethyllead
Tetraethyllead has been recognized as a contributor to soil, air and water lead pollution, and is toxic to humans. Lead pollution has increased by over 625 times previous levels in the past century due partly to pollution by leaded fuel. Ethyl Corporation historically denied that tetraethyllead poses significant public health risks in excess of those associated with gasoline itself.
Tetraethyllead was supplied for blending with raw gasoline in the form of "Ethyl Fluid", which blended tetraethyllead with the lead scavengers 1,2-dibromoethane and 1,2-dichloroethane. Ethyl fluid contained a dye which would distinguish treated gasoline from untreated gasoline and discourage the diversion of gasoline for other purposes, such as cleaning.
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