used In connection with the administration of tetraethyl lead, have given no evidence of beneficial effect.

The only general statements I care to make at this time are (1) that tetramethyl lead is much less rapidly absorbed through the skin than is tetraethyl lead; (2) that tetramethyl lead is less toxic than tetraethyl lead after it has been absorbed; and (3) that tetramethyl lead is more stable (less readily decomposed, chemically) in the body of an animal than is tetraethyl lead.

In the case of gasolines containing a mixture of tetraethyl and tetramethyl lead, the maximum concentrt ion of lead should not be in excess of the equivalent of 4 milliliters of tetraethyl lead per gallon and that the tetramethyl fraction be no greater than 2.06 milliliters per gallon. 0002716 k

Bear Captain Gilmans I wrote you a letter a few days ago about tetraethyl lead, and the receipt of a copy of Dr.

Bear Captain Gilman: I wrote you a letter a few days ago about tetraethyl lead, and the receipt of a copy of Dr.

On the other hand, I think the hogs can be regarded as quite safe from the viewpoint of percutaneous absorption of tetraethyl lead from any source* Cordially yours.

not necessarily of tetraethyl lead., ll> ass'jsiptiuns should bo i&aJe, therefore, with r& ap e ct to safety frora expoaure to lead, from detcnoiuaficn of gaadiae vapor in air.

No tetraethyl lead Is present except that minute trace vhich is the result of contact vith gasoline containing tetraethyl lead.

August 13 1957 Dr T Padure&no c/0 Komano-Amerieana Ploeatt Rcramania Pear Boater Padureanos Sara days ago I resolved from Mr# Bovan a copy of your letter of July 7th addressed to Ethyl Export Corporation In which you asked for certain information about the hazards associated with exposure to aviation benzine as die tingutahed from automobile benzine* For your infer* nation I wish to call your attention to the fact that aviation benzine does not differ materially in Its chemical compos It tern from automobile ben sine* To be sure the specifications are somewhat different but one Is dealing here with a mixture of hydro-carbons which are not materially different from those which occur in automobile benzine Bo specific studies have been made on aviation benzine Sosa observations have been mad on persok exposed to aviation benzine containing lead concentrations up to as high as 6 ee of tetraethyl load por American gallon* These results have not been pub* Itshed because they do not differ In any vise from results obtained In the study of persons exposed to automobile behslne* However a very considerable experience has shown that there are no undue hazards associated with the handling of aviation benzine even though It may contain from It oo to 6 oc of tetraethyl lead per American gallon* From animal experimentation:these results are predictable and If you will refer to one of the articles which I sent you on The Behavior of Tetraethyl Lead in the Animal organism you will find experimental data on animals which show that tetraethyl lead Is not absorbed In appreciable quantity out of benzine If the concentration is not in excess of one part per thousand* This concentration represents approximately if ec of tetraethyl lead per American gallon and is,therefore well beyond the limits of the lead concentration shown by the product supplied by Romano*Amerioana - This evidence X feel will serve to answer your question and will also show that the. statement In the artible by Major Doctor Od* Apostal is based on ads quote observation* The symptoms listed In 00i 3,1dd your latter which Dr.

Tetraethyl lead poisoning in its worst form gives an acute encephalopathy.

No tetraethyl lead Is present except that minute trace vhich is the result of contact vith gasoline containing tetraethyl lead.

part of tetraethyl lead in one thousand parts of gasoline by volume end'this talatore sold on the nsarlcet as Tfckyl Carolina.

Experiments with Exhuust Gas from Tetraethyl Lead. 17.

How will its price probably compare with tetraethyl lead?

In the matter of your statement as regards intra ethyl lead poisoning, my objection was not that reference was made to tetraethyl lead which produces a type of poisoning in large doses more serious perhaps than any other lead compound* The misleading portion of the statement consisted of the fact that reference was made to the seriousness of the poisoning asso ciated with anti-knock gasoline containing tetraethyl lead, whereas all of the evidence indicates that lead poisoning from this;1type of distribution of tetraethyl lead is non-existent.