Document jgZ36N8Nr64y15Lj4yRkJxvZR
May 14, 1945
Mips Verla M. Pond, 1101 West Franklin Street, Richmond, Virginia.
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Dear Miss Pond*
I shall do ray best to reply to your letter o May 11, and to
give you certain articles and certain references to other arti
cles that may be useful to you. I am not quite sure that I
understand what you mean by "lead transfer." I assume that
you mean the contamination of food material with lead compounds
from any source. On that assumption, I should like to point
out xo you that not all of the lead found in foods and
beverages is the result of contamination. Some of it is always
natural lead, and in many instances the bulk of the lead found
is present as a consequence of natural phenomena.
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1. ITow attempting to answer your questions, I should say that
the matter of what is permissible in various foods and beverages
13 now somewhat confused from, the legal point of view, by virtue
of recent rulings and policies of the Federal Food and Drugs
Administration. The tolerence for the lead content of sprayed
fruit was increased some months ago, (more than a year, 1 believe),
to the figure of 0.05 grains of lead per pound. This Is equiva
lent to about 7 parts per million, and if this standard were to
be applied uniformly to all food material, it would result in
our ingestion of approximately 7 to 14 milligrams of lead per
day per person. This, as you can well appreciate, is far above
any permissible level from an hygienic point of view, and as a
consequence of this fact, a special case has been made of fruit.
In general, the policy of the Food and Drugs Administration is
that it is unnecessary to contaminate most materials in the pro
cess of their preparation, and that due care must be taken by the
manufacturer or the distributor^to permit such contamination. I
am quite sure that the contamination of coffee in excess of a
small fraction of a part of lead per million by weight would be
regarded as unnecessary. Coffee beans probably contain less
that 1/10 of a part of lead per million in their natural state.
Such observations as we have would indicate that the lead con
centration 3 considerably less than 1/10 of a part-per million*
Coffee made from such beans under suitable conditions should,
therefore, be very much below the usual accepted figure of safety
for drinking water. It Is usually stated that drinking water is
safe when it contains'no more than. 0.1 milligrams per .liter.
This, we believe, is an unnecessarily high figure..City drinking
waters in general shov concentrations well under this level,
usually varying from 0.005 to 0.05 milligrams per liter. Coffee
and all other beverages could certainly be maintained well under
H 55
Miss Verla M. Pond - (2) * May' 14, 1945 -
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the concentration of 0.10 milligrams per liter. This information,
I think,! should- give you a very good Oasis for determining hat
it is safe to have in soluble coffee.
I.
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2. In attempting to ansver your question as to the effects of
lead in foods, let me say that the effects of such lead trill not
be greatly different from the effects of lead taken into the
mouth and avalloved a3 the result of other sources of exposure.
As you will see from the articles which I am sending you, the
intake of the average American varies between certain rather vide
limits,with a moan value of approximately 1/3 of a milligram of
lead per day. The absorption of lead from this source is very
slight, but some absorption does occur* The extent of the absorp
tion depends upon the quantity of lead available, and it undoubtedly
depends to some degree on the solubility of the compounds that are
available. Even soluble lead is absorbed slowly and Ineffectively
from the alimentary tract, however, and therefore alimentary lead
absorption while important Is not as prompt as we previously be
lieved . I a m 'sending you an article giving some of our studies
on the alimentary lead absorption of human subjects. I think you
will see from this article the general facts concerning the rate
of alimentary lead absorption under optimum conditions The re
mainder of this experimental work has not been published, but
certain rather fragmentary portions of it are discussed briefly
in an article included in a symposium, a copy of which also is
enclosed. i
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3. The lead that is taken in With food does accumulate in the body if the dosage from day to day is sufficient to upset the equilibrium that has been previously established between intake and output. Our studies lead us to believe that if the overall exposure po lead in food doesnot exceed 1/2 a milligram or there abouts pep day, the accumulation in the body will be insignifi cant. This conclusion will have to he proved by direct, observa tion before it can be accepted as entirely valid. However, it is supported indirectly by rather elaborate- observations made over a period of years, and I ha vb very little doubt that it will stand up finder experimental study.
I trust tiiat my letter with the articles which I am sending you will give you the information you require. If I can be of fur ther assistance, I shall be glad to do so* Moreover, if you would like to send us some samples of the soluble coffee for analysis, Iwe should be glad to analyze them. If by chance you should happen to have some coffee beans from certain definite sources, we should be glad to analyze them. We should be parti cularly happy to be able to find some coffee beans still within their1covering in such a way that no possibility would exist for their contamination. This would enable us to make some observa tions on their natural lead content and so to obtain information,
M ias Verla Mi Pond - ( - May 14, 1943 very little of vhieli is available at present.
Very truly yours *
RAK e f Sno.
^ e r r r , ""g e h o e , "iC"'!*
not.
Richmond, Virginia May 11, 1943
Kettering Laboratories University of Cincinnati Cincinnati, Ohio
Attention: Dr. Kehoe
Gentlemen:
I.am very interested in obtaining some information on 1.ead transfer, and should appreciate your either giving m<te details on the following, or advising where they may be found:
First: What percentage of lead is allowable in soluble coffee?
Second: Where can full information be obtained as to the effects of lead transfer in foods
Third: Is lead transfer cumulative, or not?
iny information you can furnish on this subject will be greatly appreciated. I am particularly interested in soluble coffee, and the answer to the first question shown above
Very truly yours,
/2J)
(Miss) Verla M. Pond 1101 West Franklin Street
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N 6194.01