Document o9JQ0kjMgGqLmyOm18J9DG7Mo

'J I 4 < 'J U / I g.o y ? COHFIOTTIJLL PLAINTIFF'S EXHIBIT Georfe ~K.l Foster MbestOS, lUrch 19, 1949 11 1<- ' ' / *V-` Tlie-report- on- experlaantal-aabestosls -haa-b aasureiewed. The expertaants-and resulting conclualona. irs suaoarized in tha attached rport, to-which I hare added 07 own cosnents and recosaendatlaas. The recoasendations are for thw industry as a whole. Seweral points need further clarification; whan these hawe seen discussed with the Saranac people I shall subnit another report. KWS/h.a. Kenneth W. Scslth, 1.0< ki'dl 4' I H i i J ` can. smocARi or rrypaog A. Parlous forma of asbestos fibres produca typical fibrosis In the lunes of iom anlmla. B. Pibrosis la producad by tha aectanieal and not tha chaalcal action of tha flbra. C. fibrosis la produced by tha lone flbraa (20-50 mlcroaa) and not by tha abort flbraa (undar 20 microns). D. Aabastoala was produced in an a tmosphere with a total dust count of 138 M.P.P.C.7. of which only 0.6 wara 10 microns or lonear. 6. Aa tha concentration of lone flbraa in tha air la in creased, tha fibrosis dawslopa in a shorter tiae. 7. fibrosis will not proerasa after ramoral from dost to norsal air. G. Aabastoala bodies are formed around fibres to prevent further irritation. H. Alunlnua therapy la osalass in aabastoala. r I. Asbestos duat causes no sicnlficant chanee in tha course of pulmonary tuberculosis. 3EX caig?3 1. Tissue and inuui susceptibility was noted la the arperiaents. Individual susceptibility to the dust among our employees has bn notad far sany years. 2. *e always hare believed that tha action of tha dust was mechanical and not chemical. If thara was an adu.J chemical effact, I ball era that wa would saa countless caaas of aabastosls bacausa wa haw a had hundrads of men exposed to zigh concentrations of dust. 3. Tha theory of tha action only by lone fibres of 20-50 alcrons Is, at first, hard to accept bacausa: (a) I personally haws heard tha lata Dr. Gardner say that probably tha most dangerous lengths of fibre for tha those of 5 to 15 Microns (b) In Dr. Gardner's latter to Mr. Sabourin of fab.23,1914, ha states: *1 believe that tha true hazard in asbaetos plants is proportional to the aaouat of small, l&dlYidual uncrushed fibres In tha ataoephere. I svtrpece Shad lhr~ reason only one sees little or oo typlcsl asbaetos Is in the alnes end mills is because there is probably too little aueh fibre In the air of these plants. Conversely the reason for the typical disease In the fabricating plants is the fact that tha processes there open the bundles of asbestos fibres and tear then into lengths Short jgggzo. to be inhal'e3~in dangerous quantitiasff. (c) In the U.S. Public Health Bulletin 42J1 entitled A Study of Asbestosis in the Asbestos Textile Industry" it is stated that the medlua length of fibres range froa 7 to 16 Microns in the plants studied. Dust counts around tha Mixing picker* and cards showed the lowest percentage of fibre and tha shortest lengths of fibre and it was among these sen (pickers and carders) that the greatest nuaber of asbestosis cases occurred. However, in spite of these three statements, I would prefer to believe in the action only of the long fibres and accept these recent Saranac findings because: J - The dust counts in our allls show 65Jt - &Q% of the fibres are 5 microns or less In length and rarely 1% ere 20 microns or longer, and we have relatively few asbestosis cases. II - The recent Saranac studies have shown that asbestosis will develop in an atmosphere of 138 M.P.P.C.7. total count of which only 0.6 were fibres longer than 10 microns. Ve have had many areas In our mills where such counts could have been found. \ 4 > 0 G / -i -2- TTT - Saranac Mao has shoi that, logically, aa tha concentration of long fibres la increased, sore fibrosis develops. The fibre danoalts In the Thetford area are of locner fibre than me Asbestos deposit. 21though "OfiTFe la no data Today, assume that tha dost in the Thetford Mills hac a higher percentage of the laager fibres than that In the Asbestos Mills, enmitnc in.JLsrt_f_or the grA$*f number of aaoestosla cases seen in the THeCford Plants. " ' iV - The relatively snail number of aabestosla cases occurring In the asbestos nines and nllls aa coapared with the textile plants night be due in part to the percentage of fibres in the industrial atmosphere. Dust counts in various textile plants shoe up to 2b% fibre while counts in our mills show only it-5% fibre. 4. That tha fibrosis of asbestosls will not progress after ramoral of the anlaal froa dust to norsel sir can easily be bellired. I have seen many men who, when transferred to non-duaty jobs, hare improved physically end whose x-rays hare shown no progression. = 5. We always hare believed that the asbestosls bodlts are not erldanoe of disease, but simply the fact that fibre has been Inhaled and tha body has shown dsfsnslTt action in an effort to neutralise the * irritation. 6. I still believe that asbestos dust will not aggravate a pre-existing tuberculosis; also that the course of' tuberculosis will not be altered In a man who has worked for several years in our mills aa . long as he has no x-rmy evidence of asbestosls. However, at tha / moment I can neither accept nor deny the atatement that asbestosls has no effect on superimposed tuberculosis. The Saranac experiments have sbown that asbestos is not an inert' dust like gypsum, nor is it a very active dust like quarts. They have shown that concurrent asbestosls and tuberculosis produce more fibrosis than does either dlssese alone. Also it has been shown that tuberela bacilli bars been found in the asbestotlc fibrosis which is not the usual site for this Inf action. These experiments have shown that there may be some connection between non-tuberculoos infection and asbestosls. I believe that this Is a fact for, although I do not think our mill workers have more respiratory complaints than the average man, I hav< seen several cases where pneumonia has developed on a pre-existing asbestosls. Such cases are extremely difficult to treat, show a verj slow recovery tnd considerable flbroels in the x-rmy. The local doc tors hare stated that pneumonia in an employee who has worked for many years in the dust often has a fatal termination. In view of the probable detrimental effect of *vsb<*stosis on suoeriaposed pneumonia, I believe thml the relationship of tuberculosis developing on a well-established aabeatosis should have further study. Although this relationship has not been shown in the recent perlments, my opinions aust be neutral until more cases of the dlseaw soong our employees have been studied. S2E1 Bwendationi 1 - Tit lr In the Asbestos and Thetford plants should be sampled and studitd for fibre lengths* tad these findings corrtlsttd with the experimental cad hrmen studlss st baranae. II - Asbestosis can be controlled if:- (a) Ertry effort 1.: made to lower tha dust ccncentratlon in tha working arts of tha employee* and (h) transfers to non-dusty jobs ara effected before any disability develops, probaWf as soon as thara ara significant x-ray charts*. Ill- Tuberculosis would not ba a problem if (ft) Erary actiTa eaaa is isolated acd not allowed to work; -- (b) non-dusty jobs ara found for apparently arrested eases;-- (c) routine case finding* examination of all contacts*ate. (an adequate tuberculous control program) was carried out. 17 - w# should hare an opinion.Iron. the.Saranac Laboratory on the association of~asbestosls and cancer. Thera la a world-wide effort to find the cause and cure for cancer. The nodical literature is full of suggested causes and asbestos has bean aentloned as a rery definite possible causa. Although in , actual practice wo hare seen no _gases_of cancer of the lung among our employees^ asbestos is"an Irritant and as such might pby sons role in tha development of carclnoaa. An expert opinion on this relationship would be worth while.