Tetraethyl lead, water pollution

No broad study of tetraethyl lead was conducted. According to Kehoe, It was thought that these necessarily extensive studies should not be repeated at present, at public expense, but that they should be continued at the expense of the industry most concerned. Kehoe proudly declared later, The problem [of tetraethyl lead s toxicity] therefore was left to a very substantial extent in our hands, where it has remained ever since. Such cooperative arrangements were typical of the 1920s in lieu of direct government regulation, industrial groups volunteered to collect technical information about the air and water pollution they caused. 

Sulfur trioxide is probably a worse pollutant than sulfur dioxide, because SO3 is the acid anhydride of strong, corrosive sulfuric acid. Sulfur trioxide reacts with water vapor in the air, as well as in auto exhausts, to form sulfuric acid droplets. This problem must be overcome if the current type of catalytic converter is to see continued use. These same catalysts also suffer from the problem of being poisoned —that is, made inactive—by lead. Leaded fuels contain tetraethyl lead, Pb(C2H5)4, and tetramethyl lead, Pb(CH3)4. Such fuels are not suitable for automohiles equipped with catalytic converters and are excluded hy U. S. law from use in such cars. 

A significant health concern with particles, especially those from combustion sources, is their ability to carry toxic metals. Of these, lead is of the greatest concern because it usually comes closest to being at a toxic level. Problems with particulate lead in the atmosphere have been greatly reduced by the elimination of tetraethyl lead as a gasoline additive, an application that used to spew tons of lead into the atmosphere every day. Another heavy metal that causes considerable concern is mercury, which can enter the atmosphere bound to particles or as vapor-phase atomic mercury. Airborne mercury from coal combustion can become a serious water pollution problem, leading to unhealthy accumulations of this toxic element in some fish. Other metals that can cause health problems in particulate matter are beryllium, cadmium, chromium, vanadium, nickel, and arsenic (a metalloid). 

Synonym tetraethylplumbane, lead tetraethyl Formula Pb(C2H5)4 MW 323.47 CAS [78-00-2] used in motor gasoline as an additive to prevent knocking such an application, however, is currently curtailed because of environmental pollution boils at 200°C vapor pressure 0.2 torr at 20°C density 1.653 g/mL at 20°C insoluble in water slightly soluble in alcohols dissolves in benzene, toluene, hexane, petroleum ether, and gasoline highly toxic (Patnaik, 1992). 

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