Document bybzqza59wjY038eNe7dZdqE6

September 8, 1954 Mr. A. J. Baldwin Mr. L. R. fleck Ethyl Corporation 100 Park Avenue New YorkCity i? Gentlemen: I send you herewith cops [rdr`. copies to Mr. .fleck) othe analytical findings on eke hose iir.e ent come time ago. (The results v;erc Me tracked tnrough scmo vs ry *,the vacation period, j ' The further copies can os unit with as you may desire. 'four critical consideration of the data and the interpretation are invited. It is possible that we may wish to carry these observations further. I have asked Mr. Chela!-; to study the effects ci paaii:&air throuesi .*c<=gient of this hose, thento clean it with dilute acid andv/ator (on the inside) and to repeat the observations. After that we shall see what, if anything, might be done further. Cordially yours, RAKef Eac. Robert A. ilohoe, M. D. 0010481 INTERPRETATIONANDCOMMENT The samples were so chosen andanalysed as to portray, if possible. (1) the influence of external contamination of the hose with tetraethyl lead; {2) the extent of the penetration of tetraethyl lead into andthroughthe rubber. ' S;/ ' ' thereby giving rise to contamination of the interior surface {andair passing \ \ through}; (3) the extent of the contaminationof the inside othe hose at the ooirst ox the break.in its structure; and {4) the extant of deposits of particulate load (decompoaitionproducts of tetraethyl lead and/or other possible compound of lead in particulate form} onthe outside andthe inside of the hose. That is, if sufficient difierencou inthe quantities of tetraethyl lead and its decomposition products andoi inorganic lead could be found at various points represented by the samples, it might be possible to discover,* the nature andorigin of the contamination, whether by penetration of tetraethyl landthrough the intact rubber or by the entrance of sludge and/or other foreign muterial into the lumen through the break in the wall of the hose. The following conclusions appear to be justified; 1. It does not appear that the intarioirof this hose line was contaminated with organic lead to any very much greater extent at the breakthanat the other point. Such contaminationas occurred appears, therefore, to have been the result oi the penetration of organic lead throughthe rubber structure of the hose* 2. The contaminationof the inside of the line with organic lead was greater than that on the outside, this fact tending to support the conclusion arrived at in {l) above, and indicating that the cleansing of the outside of the K 0010482 2. hose fromtime to time had reduced the external contamination. 2. The meaning of the results on inorganic lead is not clearly avident, since the amount of inorganic lead in newly manufacturedhose is unknown. It is probably a significant amount* andit maynot be muchless titanthe lowest analytical value obtained, i.e. J.&,9mg. per foot of hose. The highest value obtainedonthe outer part of the hose is probably an expression of the uneven external contamination of various outer parts of the hose Une. The essential uniformity of the results obtained by the analysis of the two inner samples indicates that the break in this hose was not a factor in its internal contamination. One might make the guess that the inorganic lead found in the inner portionof the hose is the combined result of some initial quantity of lead which entered into the original compo sition of tiie hose, plus some quantity of the decomposition products of tetraethyl lead which penetrated throughthe rubber wall of the hose, plus some considerably greater source of lead deposits on the internal surface of the hose. Onthe whole, it is scarcely credible that a hose line containing the quantities of volatile leadfound by these analyses, could continue to yield from its inner surface to the air streamflowing through it, such quantities of lead as to contaminate the air to any significant extent. ocoo It is believed that if sucha hose line as this were cleaned in the ordinary manner, by being washed inside andout witha streamof water, and oo thendried out by a streamof air, it wouldnot give rise to a significant Vu amount of contamination of the air flowing through it at normal velocity. This is to say that, inour opinion, a significant degree of contamination 3. from some source in one or another length of hose, rather thanfromthe penetrationof tetraethyl lea.il from the sludge throughfit`all of the hose. Some further observation will be made to teat this opinion. It seems likely that hose lines shouldbe inspected carefully, cleaned inside whennoceasary, anddiscarded whenthey begin to go to pieces. .Further comment will be forthcoming onthis procedure when the further observations have been completed. Signed vooort W * September 3 195*1 0010484