Louis, 722 Chestnut Street;San Francisco, 2240 24th jSujeet; Boston, National-Boston Lead -Co., 800 Albany Street; Pittsburgh, Nodosal Lead. & Oil Co. of Pa^ 316 Fourth Avenue; Philadelphia, JohnI T.

Marbaker Research Department Leo S* Smith and Son Mf g, Co* 7525 Penn Avenue Pittsburgh* Pa* Dear Mr* Marbaker: In aa mu c h as I shall he away from the laboratory for the next tmo or three months* I aa replying to your letter of June 12th and turning over the correspondence to m y associate Dr* W* P* Machle* who will be prepared to work out any subsequent development of this matter if it becomes advisable to proceed before I return* In view of the prevailing attitude toward the use of lead containing materials* I should advise against your use of the lead compound for the purpose whlph you have in Blind* if it could b e avoided* I think it probable that the use of lead in the manner you describe would be in no wise hazardous* hut on the other hand* it seems quite probable that its use for this purpose would be questioned* and that if difficulties arose* you would have to b e In position to defend yourself not only against criticism but against dtusage suits* I do not see how protection could be provided except on the basis of experimental work of a very practical sort* In my opinion* it would be advisable to test the solubility of the lead in the "Vlnylite* In various aold and alkaline media* This* it would seem* could be done as well in your laboratory as here* It should also be established* I believe aa to whether there is any appreciable solution or disinte gration of the dentures under conditions of actual uae* The latter would require the cooperation of a sul table subject or subjeots* and the fate of the dentures could be determined cither by determining the residual lead, in them after a definite period of wear* or perhaps by following the lead excretion of the subject with and without the den tures* In any oase* I believe experimental work of this general type should be carried out if you consider it worth while to use this type of denture* and if you desire this type of work* we are In position to carry it out for you* tr B 00137 The cost of such work will depend, of course, upon a number of factor such a the employment of a suitable subject or subjects, the duration of the experi ment, and the number of analyses which might be required to determine the facts* In any case, the cost of this experimentation would run into same hundreds of dollars* It would perhaps be well for you to determine whether such expenditures are justified before we consider the details of the experimentation which might be carried out.

Despite this fact we have never been able to find evidence of significant lead absorption In the mixing personnel.

Lead concentrations in the blood and urine of the order of magnitude described, are seen only in association with very severe lead exposure.

Kitmiller* and after taking into account the various findings# First* let me point out that the results of lead analyses give a clear indication that this man's lead exposure was of the sort which in our experience can produce lead intoxication.

An asbestos-free and lead-free composition friction material, compnsing, by weight, 0 5-11% fiber, of which at least 0 5% is synthetic fiber, 66-81% filler and 14-21% organic binder The friction matenal of claim 1, wherein the fiber content includes at least 1% glass fiber 3 An asbestos-free and lead-free composition friction matenal, compnsmg, by weight, 1 5-10% fiber, of which at least 0 5% is synthetic fiber and at least 0 4% is cellulose fiber, 66-80% filler and 14-21% organic binder 4 The friction matenal of claim 3, wherein the fiber content includes at least 1 5% glass fiber 5 An asbestos-free and lead-free composition friction material, compnsmg, by weight, 5-10% fiber, of which at least 2 5% is synthetic fiber and at least 2 5% is cellulose fiber, 72-79% filler and 14-19% organic binder 6 The friction matenal of claim 5, wherein the synthetic fiber is glass fiber 7 An asbestos-free and lead-free composition friction material, compnsmg, by weight, 2-5% fiber, of which at least 1% is synthetic fiber and at least 0 5% is cellulose fiber, 72-82% filler and 14-21% organic binder 8 The friction matenal of claim 7, wherein the synthetic fiber is glass fiber 9 An asbestos-free and lead-free composition friction material, compnsmg, by weight, 0 5-7% synthetic fiber, 72-81% filler and 15-21% organic binder 0 The friction matenal of claim 9, wherein the synthetic fiber is glass fiber 11 An asbestos-free and lead-free composition friction material, compnsing, by weight, 0 5-2% synthetic fiber, 74-82% filler and 15-22% organic binder http //patft uspto gov/netacgi/nph-Parser?

Division Lead Co.

It Is true, of course, that we have 'worked much and published sparingly, but I should have thought that Robinson would have seen Bambach's paper on "The Plasma - Cell Partition of Blood Lead", with Its extensive Investigation of the behavior of lead In the blood of rabbits, and its slight but relevant data on the blood of adult men.

This is suggested onjithe basis that Vitamin D increases the absorption of lead from the intestines.

Dr0Augusto M,,Viera, Director of Public Health, Belgrano N8666, Buenos Aires,- Buenos Aires,May 7th*1945 Dear Sir, Decree NB7584/45 dated 9th,April 1945 establishes that the Director General of Public Health will excercise control over and fiscalise the manufac turing,distribution and sale of the lead compounds referred to in the said decree and that your Department must submit for consideration of the Government within 90 days the necessary regulations for the excercise of the control referred toe My Principals,The Associated Ethyl Company Limited,are the successors of Ethyl Export Corporation who,through their parent Company,the Ethyl Gasoline Corporation,pioneered the manufacture and distribution of anti-knock lead compounds in the year 1923* From the start,we have insisted on the medical supervision of the men engaged in manufacturing and blending operations of our product* We have a Medical Director - Doctor Robert A0 Kehoe - Frofessor of Phisiology at the University of Cincinnati and Director of the Kettering Laboratory of Applied Phisiology - University of Cincinnati* Doctor Robert A* Kehoe and his assistants have made a detailed study of lead intoxication,especially in regard to lead tetraethyl intoxication,and his studies have been recognized the world over by doctors and official medical bodies wno have been guided by them* In each country where lead tetraethyl is used,it is the custom of our Company to appoint a medical consultant,instructed on the subject by Doctor Kehoe, and this medical consultant is in charge of the men engaged in manufacturing and blending operations of lead tetraethyl* In the Argentine Republic our medical con sultant is Dr*Alfred Pavlovsky,who has not only had the opportunity of discussing the matter personally wJ.th Dr,Kehoe,but has also,since 1940,been in charge of the examination of the men engaged in blending operations at the Government Refinery in Ensenada,as well as at the Refinery of Compania Nativa de Petr^laos S0A0in Cam- pana* In view of the above,I take the liberty of suggesting the possibility that Doctor Pavlovsky be invited to co-operate with the committee entrusted with the drawing up of the regulations foreseen in Article N25 of the Decree referred to.

The subject of possible lead poisoning hazards to personnel engaged in the transportation of leaded gasoline on tank vessels seems to persist in spite of our efforts to show that no ill effects have been suffered by any one to date.

Scales Ethyl Corporation 1600 West Eight Mile Road Ferndale, Detroit, Michigan 43220 Dear Dick: I am sending to you, herewith, a copy of a report of the progress of the investigation of the fate of inhaled lead, in its present relation to the tolerable concentration of lead in the ambient air.

paint which doesn't. cr-ctck' _ i perstJi< NATIONAL LEAD COMFA and scale!

POTENTIAL EXPOSURES IN INDUSTRY 2243 Armature Workers Lead "tinning" baths and lead pots, when small and equipped with tempera ture controls, may not present serious lead exposures.

All water systems that sample for lead and copper must provide a consumer notice of individual lead tap results to each location where samples were taken within 30 days of receiving results [40 CFR 141.85(d)].