Document jy3pZerEyvEELyXjwgLjjbZRQ

It anwri chat tha data analysed was iacoaylata, aa tha findings are lncoocluslva. Dr. Villiaai S. Splcar, Jr. tacionaanda that a coaplata apidanlologic and physiologic study b don* In tha oaar futura. I would a.praclata your cowanta on the ruggaatlona aada by Dr. Splcar. I truat that you will be in agraa--nt with tha racowandatlona and that tha Maryland Casualty Conpaay, aa part of thalr sarvtcaa, will procaad with thla atudy. Vary truly yours. FVRiXL Enc. cc: J. Paul Cahalana J. A. Kallay' X. A. Blaich` 0. F. Stewart T. V. Rupp Treasurer ro'Saff'T l5l4<?*36 '$'A*oanr K------ . ~^ssjE-*': > * :r& ** ........... ;-,*fcV>-v:ft;m'' o r e' j^S...i.X.....r.V"' ia m o Enclosed, please find a cooy of the report to us frca Dr* WiiDiaa S. Spicer, Jr., on the situation, at the Zonolite plant in Liboy, rlontana. Dr. Spicer is recognized to oe one of! the authorities on lung conditions in the country. 1 vou*c recomend that Dr. Spicer's reconnendations be carried out. Very truly yours, V S' - vV / Robert r'. Chenowith, K. D. REC/acs Enclosure cc: Dr. .-'ocdro'rf ielson i.r. a* . he?vV</0e nr. * Rurx 1. S.: V?e are returning the chest x-ray reports, spircneter tracings, etc., to you unset separate cover. 15142437 . . ruwu SCXOOU or MS3IONS . .... w .* "-... v a.* sir-i We have completed.our reviewof tie/groupr o;recorda of the employee s e Qanpanv who ar^aeibHkted with th^ZOITOIrS<>ricion ia north.- gotara Montana. ,v .g- ^ W$'&$ I have chosen to approachthis from the point of view thatthe Grace Company is desirous of maintaining this operation while ' taring bcdi themselves and their employees of the smallest possible risk of hea? hazard from die develop* meat of pulmonary asbesto sis. You will find enclosed the original records plus: 1. A brief s ummary of the literature. 2. An analysis of the health records. 3. An ou:line for an epidemiological study of the effects of this industrial hazard. I would summarize our thoughts and recommendations in the following way. I have nothing but the highest respect for Dr. Nelson in undertaking this study while carrying on a busy practice. However, he suffers from a lack of equipment and personnel needed to perform an adequate evaluation. While many of the records are unsatisfactory, a plus 20% x-ray incidence of pulmonary infiltrate plus some confirmatory physiologic evidence would suggest that this plant has an important health problem. This is particularly so, as respiratory function tests of the type he performed are aimed primarily at eliciting obstructive airway disease while pulmonary asbestosis is primarily a fibrosis or restrictive disease. In other words, should more sensitive tests, i. e., diffusing capacity, lung compliance, work of breathing, arterial blood gases and ventilation at rest and exercise, and total lung volumes and airway conductance be applied I would not be surprised by a doubling of this incidence of disease. A second point to note is that in any group of workers such as this where a majority are cigarette smokers one can expect to find a prevalence of 20% or greater of obstructive A Century of Democratic Opportunity in Higher Learning 151424 38 . 'vv,H- - - - - - . . -' . . 'V- ,.. ."sr^r discisc on tnc oasis of smo< mg when sensitive tests and questionnaires rirtuiili-4cc. The company cannot. <* w'^d responsible for thisxhscaso.In add!cion ay*-*a' _. ofast can be expected in the adult population. ..... '*>*^r*c*4v4.;**-isfi<tt-hn*?e**Sf'c# ompany olans to^evaluate^this Health problem^itshoulcn'c be tnout theassurance of a. commppljMt^pidexniologic and physiologic work-up must'be taken that,, y^V'le-? *fl-!' Iff ""^electibnbf.respiratorslgnd^Slests' purnlnffthat a few sophisticated tests icuarworkers wonlt complete 1 cu'msta..n. c..eV _ st such, cases rcl^ill^reveal'defects ii.i.i, .f p55rejkvs*i7o. usly ipart from their unwitting, failure xa a compl *S"H"iSyyppIa.h.. a*t the outset. .I.w..ould recommend ato,*.j. t___ iblbgitTandphysiologic ie nea_r_,___JreSjfollowed by the institution of whatever ___control measures are deemed necossaryand a, repeat of the" testing procedure cia^l^^thzeeyeaurs; pZnadditxonr a matched,' control group of workers not exposed fto^asbestos be studied, possibly from another Grace Co. operation, eg. Davidson Chemical, etc. Such a study would be costly as it would involve moving a team of Imres? itors and equipment to Kalispell on two occasions plus the study of a control group. However, it has been my experience that the cos; of such a study very seldom exceeds the size of one lawsuit resulting from industrially acquired disability. It is possible that the Div. of Occupational Health, U. S. ?. H. S. would support such a study. It is undoubtedly ar.ticiimatic to note that we have the personnel ar.d experience to cc such a study and I will be speaking to the Montana Academy of General Practice this June. Should you have any further questions, I would be happy to attempt to answer them. Sincerely, WSS'.skh Enclosure WILLIAMS. SPICER,/jR., M. D. Head, Division for Pulmonary Diseases l5l4439 IW9 .'Tr satisfactory. - (fsvi) The forced expired volumes in 1 second^are expressed as % of predicted normal for 1 second. These and the maximum expiratory flow rates (MEFR) were categorized: 1 = good, 2 = fair, and 3 = completely unsatisfactory record. The chest film reports were graded according to the asbestosis classification used by Williams and Hugh-Jones (1). Each lung was divided into thirds and each area graded 0-3 for no, slight, medium, and heavy mottling (grading 0-13 for no to maximum involvement from asbestosis). Pleural reaction was also recorded, i~ i'twj eery <. T u'.S -x+n~. 'C,. K-ny fcKti >urti-A.YU t--aj( <J.seer Results: Radiological Changes compatible with asbestosis were present in 20. 67#Aof the plant workers: 397* (18 subjects) of these had pleural reaction, presumably from asbestosis as no case of pleural reaction was reported in the absence of evidence of asbestosis on x-ray. The severity of asbestosis .;oars to be related to the total duration of work and to the duration of work in the mill (table 2). The x-ray grading %ystcm of 0-13 would classify 26 of the 28 workers with asb stosis as having 15142440 ; b; 'JSL mia-KVAi caacasc 'jriaa as havingmodarately advanced disease (crade 7-U' vVjv~:'-f{-,'^vv.. - V^ffifT ih - .- - '' and acne as Havinganadvanced.disease- f ' ips-among spirometry,x-ray evidence of asbestosis and work history are seen in Tables 1 and*2. It appears that the FVC and MEFR values in those without osbestosis on x-ray- are slightly below normal. This is probably a result of submaximai effort on the part of the subjects. The FEY^ in this same group is within normal limits. Relative differences between the different groups suggest mild decreases in the vital capacity, FEV1 and MEFR in those with asbestosis The FZV1 may be worse in. the mill workers. No definite changes in spirometry are seen with increasing grade of asbestosis however, the number of cases in each group is small. Discussion: This study indicates a 20% incidence of asbestosis in workers studied. Crude spirometry suggests that this group of affected workers have mild restrictive and obstructive ventilatory insufficiency. The 4 city employees studied revealed no definite trend. No evidence is present to indicate that they have benn affected by asbestosis. 1. Williams, R. and P. Hugh-Jones. The Radiological Diagnosis of Asbestosis. Thorax, 15:103, I960. 15142A41 i ... . "*'*J**k ;; ti.y ;^5!55IB9WBWS*- MB 3. MSFR = maximum expiratory flow rate. Normal greater 300 liters/s Tabic 2. Spirometry vs. grace o asbestosis (mean values) X-Ray Grade 1 Xo. Cases 7 FVC ot pred. 62.0 (2)W FZV1 5s o pred. 70.7 (7) M2FR liters/min 232 (3^ 2 3 76. 0(1)" 66. 5 (4) 275 (3) 3 5 53. 7 (3) 83.0 (3) 190 (3) 4 3 84. 0 (2) 92.5 (2) 225 (3) 5 2 75.0 (1) -- (0) ----- (0) 6 1 36. 0 (1) 77.0 (1) 140 (1) 7 1 64.0 (1) 48.0 (1) (0) S 1 79.0 (1) 33.0 (1) 200 (1) Total 23 means 30.7 (12) 74. 1 (19) 222 (14) Mean all workers * Values in parent:hesis indicate no. of records. Total Work Months Mill Work Months 134. 1 63.0 160. 2 55. 3 i56. 3 91. 2 150. 3 116.0 213.0 123.5 189.0 171.0 139.0 106.0 31.0 31. 0 155. 0 93.4 101. 5 55.4 , 1514244 2 STUDY TQP^THgnSFFECmg-' AN ICTUmiALv HA2ARD ^ ;tfr;` . * .- {hospital & medical' records) ^c'ause'ind contributing causes of deach (death certificate) B. Review of reasons for: * premature retirement) job changes ) in the industry as a whole and by divisions within the industry related to exposure C. Evaluation of present health status of current employees and com parison of their health status with that of similar men not exposed to asbestos. The control group would have to be carefully chosen to allow similar probability of illness and/or degeneration for all other reasons except exposure to asbestos. Demographic, historical, personal habits, socio-economic and medical care factors would have to be considered. Measurements of present health stares used for comparison would include: medical history of morbidity; results of standardized physical examination; and objective measures of body function. IX. Evaluation of Effects of Control 1. Change in incidence 2. Reduction in progresssion of disease. (a) An objective definition of abnormality would have to be defined, (o) The prevalence of this abnormality would be determined. (c) An estimate would be made of the median time of exposure in those who show this abnormality. (d) The prevalence would be re-determined after a time approximately equal to the median time for development of the abnormality used as the criterion of change. The incidence would be calculated. rx ' ',W|RP gL|P 15142443 **l (b) Search for morbidity data Collected by che National Health Survey. (c) Execution of a morbidity survey among a sample of che population to compare either with the results of che National Morbidity Survey or a survey among a selected control population. (d) Comparison of diagnoses of age specific hospital admissions with published data or with a specially collected control sample. To evaluate the affects of control or removal of any hazard--some or all--analyses would have to be repeated after a stated interval of time (probably 5-10 years). w.. 'm 'itijw imuj v*"1 * 151*2*44 - l.ITXP.A'nncr summax?----- -------- :----- --r.k------- ' ^Although we appreciate that the industrial physician fa-wit 2 :'-rtet&T. The human studies suffer from the fact that they represent only the *d stage of the disease and they do not give insight into the early developmental processes. The animal studies, on the other hand, do not necessarily parallel the human findings while they do give some insight into the development of the disease. Summarizing both together we can point firstly to the obvious discrepancy between the actual weight ox silicates found in the lungs 01 asbestos workers at autopsy and the severity of the disease. This simply illustrates that not all individuals respond to the same degree nor on the other hand are all asbestos fibers of equal potential toxicity. The primary pathologic lesions are ox two types: 1} a nodular development in the small bronchioloes; and 2) a fibrosing lesion which can lead to the scarring and obliteration of alveolo-capillary areas. Even in the British populations where the incidence of centrilobular emphysema and chronic bronchitis arc high the asoestosis workers demonstrate very little evidence of emphysema although occasional bullae and centrilobular changes are found. In at least one report, far advanced cases will tend to show a high incidence of bronchiectasis. The other classical characterisiti.cs of the disease are the marked pleural changes and the development of both pleural and lung malignancies. 15142445 iw iy '-i V. -TS, ?r<r<ArV fatnnlngicl eg; pg_jg a, fibrosis.-at the-level-oi-the- smal lung radicals and alveolo-capillary surfaces, usually with minimal secondary obstruct!'.- .-^5^4^'%eauuous <>%$.>?: . * - .v*>v ^7tAcfSSec%o^^enasbestos fibers, in the less than 10 microns in length size, by the alveol: s ft-v.tAa^g.v^ja^jWhd*;-' - --*"? ':- - - . -**!**&*.* -*.v. - . > acgQr^gq.% jM ^gocytes^rheTfriaxa: somtf thoughtt^hat tbe^Bbrosis caa occuSl^K: WtOX itlV folio~winIV7- =t>h>eI'-Mtrrr.n iltinfl af mtnniura dn^tn-thli liminlrinn -w4 ' ">v-":' ; isM#fihirs- which aa^asaafc.^.** ^ h avenbiii'e-rerriniimennincnilroaasreTfdTiiianH:aiifi.ffpJraomteainaceous^material.^f...<'l'w#.*_; , ---------- ...... -.- icaXTanc Radiologic Picture in. Relation to Pathologic and Functional Change. '-' :'*-*.&.*C*tj#j&'&J&.'j.*r--r. .-; ' - --'-L,i' >;a.-..`-..',' ^V.--v'-V" v. The cUnical picture of thesepatienf *ls tisuatty tlai^ block** element that any'respiratory disease-which. wouldbe common to the' :^community,:'Lo. chronic bronchitis^may cause a significant overlay. The classical I. clinical picture of alveolo-capillary block is that of a small lun nth minimal physical signs, dyspnea at first on exercise, eventually at rest, accompanied by clubbing and cyanosis with right ventricular strain and eventual failure. It may be important to point out that such patients do not appear to be short of breath to the examiner as early in the disease as do patients with obstructive airway disease where the work of breathing utilizing accessory muscles of respiration is obvious. There are considerable discrepan cies between the x-ray picture and the clinical symptoms on the ofhr hand and/or the respiratory function tests on the other hand. In general, one may say that the presence of an x-ray lesion strongly suggests a more severe disease. However, when one comes to the important question of progression of the disease either in the presence of continuing exposure or after cessation of exposure the x-ray becomes a less valuable tool. Clinical and physiological progression is not uncommon in the absence of s-ray change. Physiologic evidence of disease has been described in the presence of negative x-rays and would be anticipated. Again, x-ray, clinical, and physiologic severity are related to thulongth of exposure however, there are many examples in the literature of cases 15142446 os' short :t;.urcxpoavn:e,-i. e.yl8il4 munths-wiili sevexe-discCTg; The physiologic testing results are what one might expect from the pathologic results. Thesysould be small total lung volume, an increase in compliance, a reauctic . ' = -'V V' in diffusing capacity,, with either normal or borderline arterial oxygen tensions at rest .. . . :-- " which fall on exsxcueTacIeast during the acute stage of the disease, and alveolar -' *|p9p v>": . ' "i- ..- .a hyperven tfie other hand, obstructive airway disease plays a very small - part and in case one shoifi note that tests such ae the forced vital capacity and FZV-l. sec. are aimed primarily at determining obstructive airway disease. It is equally important to bear in mind that with the high prevalence of chronic obstructive 5 -;.;:`V'., .- . airway diseasewhich is present in the population of this country, probably secondary .. to*'- **"> , -;rf , to cigarette, smoking, that the identification of such disease by objective methods such % as the measv .meat of airway resistance or conductance and residual volumes would be important in separating its effect from that of asbestos. I w 151.424*7