Document Z8XBrQaXkD20N5BRyBz2dDeE8

FILE NAME: US Gypsum (USG) DATE: May 1937 DOC#: USG039 DOCUMENT DESCRIPTION: 1937 Progress report from Saranac Lab with cover letter to JS Offutt. 1 COPY. j c z m s -m a m v i l l s c o r p o r a t i o n TWENTY-TV/O EAST FORTIETH STREET NSW YORZ, N.Y. May 11, 1937 Mr. J. S. Offutt, Assistant to President, United States Gypsum Company, 300 West Adams street, Chicago, 111. Re - Dr. Gardner - Asbestos Dust Experiments Dear Mr. Offutti Replying further to yours of April 29, 1937, I am enclosing herewith copy of Dr. Gardner's first progress report dated May 5, 1937. 1 t Very truly ycurs, V3:T BD Enclosure /s/ yandiver Brov/n Vandiver ^rown General Attorney Z/ FOR 10. AS OF DEP. EX. f!0 . z C 0 '?.1' V ' 'v-- V First Progress Report on Asbestosis Experiments at the Saranac Laboratory. Kay 5, 1937. "" . To furnish a better understanding of the disease, asbestosis, and to '~ p r o v i d e standards as a basis for its diagnosis by x-ray films, a group c animal experiments has now been started. T-: " .- . " It is expected that anatomical-changes rill be produced in the lungs of animals inhaling fibrous asbestos which rill cast shadows on an x-ray film comparable to those seen in human beings. Since the animals can be killed as seems advisable it will be possible to compare the anatomic changes in their lungs with the shadows seen in the films. To make certain whether the fibrosis in the lung is due to the chemical composition of asbestosis or whether it is the result of a mild irrita tion in the walls of the air spaces resulting from the action of a fibrous foreign body (l.e. its physical structure) injection experiments are in progress. If no fibrosis results from accumulations of asbestos in other organs it may probably be assumed that chemical stimulation of the tissues is not responsible for the pulmonary fibrosis. As a further check on the physical vs. the chemical hypothesis, the action of ground serpentine is being compared with that of chrysotile. Since they~both have the same chemical composition the comparison should be instructive whatever the result. To check .the effect of mere fibrous structure, a search for other fibrous minerals was made. Rone other than those classified as asbestos could be discovered which had the same structural composition, -orever, because of our interest in the action of gypsum, a sample of satin spar (fibrous) and also one of soda tremolite were selected, for comparative testing. Finally, the action of various members of the asbestos group, amphibole, amesite, crocidolite and anthophyllite are all being compared with that of chrysotile. It is too early to report more than the fact that the experiments have been started. For the inhalation of chrysotile, a dust ,iurnished, by Mr. Fisher from a plant at !ianville,_N.J. is being employed. As it* " was received, the dust-was not' sufficiently fine for experiments of this type and were forced to regrind i*- in a ball mill. Considerable time was scene in experimenting with a proper type of mill for the purpose, this difficulty was overcome and* inhalation '.vas begun on arch In the dusting room we placed 30 guinea pigs, 20 rats, 8 rabbits and 3 cats- More of the latter will be procured as they become available. ltb.r ? r^ rfv~ ViS-.'1' i r*r ;P aA dust concentration of approximately 175 million particles p?;er cubic foot of air is now being maintained. This'may later be chansed. Over 9C of *h? particles are less than 5 microns :r. , diameter. Since significant results cannot be expected to develop until exposures have been continued for from 1 to 2 years there can be little to report before the expiration of that time. The various injection experiments are further advanced although it is too early to report any results. For this purpose all dust's have been analyse- chemically and petrographically. They were then ground and fractionated' by allutriation. ^nly particles 1 to 3 microns in diameter were used. Their composition war again checked by the same methods of analysis. The various tests are tabulated for your information. Chrvsotile fThetford) a. Intravenous Injections. Eave prcvd difficult. 7 rabbits have died, apparently from mechanical effects, without receiving significant quantities of the dust. Further attempts are in progress. b. Intraperitoneal Injections - 5 guinea pigs, Harch 31, 1937 One killed after one month. No gross fibrosis. Anuhibqle a. Intravenous Injection. L rabbits still in progress. Have each received 11 doses totalling 0.55 grams. Mo fatalities'. b. Intraneritoneal Injection. 5 guinea oiss. Feb. 5, 1937 ` ' 2 killed after 12 and 30 days respectively. Dust plaques without gross fibrosis. Amsslte a. Intravenous Injection. L rabbits still in progress. Have each received 11 doses totalling 0.55 grams. Mo fatalities. b. Intraperitoneal Injection. 5 guinea pigs on Feb. 5, 1937 2 died of infection. 1 killed after 1 month. no fibrosis. Most of the cuss absorbed; ssS'se*,.t,``&'C Crccicolite a. intravenous Injection. A rabbits.have eachreceived full dose of one gram i n '20 injections. None killed. . . . 1* 1 - ' 'i* t . . * * ^ l -,-rbrTr.-Intraperitoneal -injection. 7 guinea :pis - ' -.j. . . . . . *>** 2 died of infection. " '---in* . . ....... 1 killed after 1 month. . Pigmented dust plaques without fibrosis......... Antnorhyllite .... a. Intravenous Injection. A rabbits have each received full dose of 1 gran in 20 injections. 2 killed after 3 1/2 to 6 months respectively. No evidence of fibrosis in the lungs, spleen, liver or bone narrow. b. Intraperitoneal Injection. 5 guinea pigs. -, ' : 3 killed after 1, A and 3 months respectively. _ Disappearing reaction with gross evidence of ''fibrosis. * Serrentir.e . . a. Intravenous Injection. L rabbits have each received full dose of 1 gran in 20 injections.. All alive and well. b. Intraperitoneal Injection. 5 guinea pigs. 2 killed after 1 and A months_respectively. Soft pigmented dust plaques without fibrosis. gibbous Tvnsun - Satin Soar -- Intravenous Injection. L rabbits^have each received 11 of 20 injections, or a total of 0.55 grams. No fatalities. ' - > b. Intraperitoneal Injections - not mace. Soda Trerolite . * - a. Intravenous Injection. A rabbits have each received total dose of 1 srau.'in 20 injections. All alive and well. " b. Intraperitoneal Injection. 5 guinea pigs. 1 killed after 1 month. Snail pigmeoted dust ; ' t c '-*> ***; - */.* . ;7 . -' S& S& h .J . - / - .* . * i/ ;- - 'iiiin C ii.V ' * ;i- . > -- i - . ' > 3 - rf S . . - - -` V - -* - \-j~ - ... ' i * * ` plaques without fibrosis Mone of these early results is regarded as significant and no ccn- cj-usisns rill he d r a m until the observations have been continued i.or at least one year. It is not yet clearvrhether the difficulties with intravenous injections of chrysotile are merely a natter of technique or whether this substance is essentially toxic, V'e are'attempting to discover the cause.