Document 91z3rvB0J5jZJNoRKvyGorrqp

FILE NAME DuPont DUP DATE 1969 Oct 2 DOC DUP008 DOCUMENT DESCRIPTION Memo - Personal and Confidential - to J.P. Morgan Haskel Laboratory from Charles D. Crook RE Method of Reporting Asbestos Dust Levels with Attachments 1-5 . eee a ae : . GU PONT : Coot Te CC J. E. Crawley ' So C. H. Lueck es J. J. Perkins E. DU PONT DE COMP & A COMN PAY NY \ BRATED OLD HICKORY TENNESSEE 37139 ,D. D. Drummond WILMINGTON * J. A. Sigman 2 WILMINGTON , TEXTILE FIBERS DEPARTMENT mS 7 a . Hickory Old _ Tennessee October 2 1969 PERSONAL AND CONFIDENTIAL Morgan Morgan 5 RECEIVED CERTIFIED SHORTHAND REPORTERS PERSONAL EXHIBIT P - EXHIBIT ~> G j X Morgan < a2p, =H P. oo ON DATE 10-23-86 Haskel Laboratory + MASTROIANNI & FORMAROLI INC WILMINGTON , 7 . 1969 OCT - OCT 31 HASKELL LABORATORY Ref METHOD OF REPORTING ASBESTOS DUST LEVELS 40 . and subject 1 Telecon C. D. Crook J. P. Morgan same 9/11/69 2 Letter D. D. Drummond to P. J. Tracey Asbestos Dust Analysis 8/21/69 - . 3 Private communication with Jeremiah R. Lynch Bureau of . Occupational Safety and Health U. S. Public Health Service 1014 Broadway Cincinnati Ohio 4 Threshold Limit Values for 1968 American Conference of ( ; Industrial Hygients St. Louis Missouri > 6-8 Hess 5 R. J. Blair to 0. W. Asbestos Exposure Hazards ... - Per reference 1 I have formalized what I believe is true about re- level porting asbestos dust level and request youropinion by return letter Our eventual agreement will determine how asbestos dust will be reported within the Textile Fibers Department ~~ 4 ; Please comment concerning the following two items dust 1 The best method to report asbestos longer than 5 microns in length level is fibers per milliliter milliliter . 2. r ro Construction Division's adoption Ref 2 of 0.5 million fibers per cubic foot less This may be questionable for two reasous of an asbestos than 5 microns dust level in length long It ignores the fibers which are known to enter the lung and cause asbestosis ' It applies a numerical tolerance value intended for overall dustiness fibers plus grains as measured by the impinger method to fiber dustiness grains not counted as measured by the membrane filter method As a result their tolerance value . ~ is above that recommended by the U. S. Public Health Service ve . Ref 3 and the American of Governmental Industrial Conference Ref 4 Hygients e- -_ October ; | Om Boe__ October 2 1969 established long Ithas been that fiber do enter the lung and womans cause must III - asbestosis Therefore the concentration of long airborne fibers be controlled see Attachments I II and oT ee Te wy rd It is not known if short fibers cause asbestosis Some studies show short fibers to be inert Attachment IV others indicate they could be as harmful as long fibers Attachment V The U. S. Public Health Service does not consider short fibers inert but maintains that is low level will if the long fiber level also Ref 3 then the short fiber . be low Reference 5 specifies that 0.5 million particles per cubic foot to be used as a tentative tolerance This was obtained by taking tenth of official governmental standard But the governmental standard is for overall dustiness fiber plus grains Obviously applying the same numerical value to fibers only gives a high tolerance value 0.5 million fibers per cubic foot is equivalent to 18 fibers per milliliter the fusion governmental standard forfibers is per milliliter To avoid con- in the futureI recommendthat we always talk in terms of fibers we or es . as LhDACRONG MANUFACTURING DIVISION - oven PROCESS SUPERINTENDENT . CDC Attachments . a VA : : INDUSTRIAL HYGIENE AND TOXICOLOGY } TOXICOLOGY - . , . . VOL I. FRANK A. PATTY INTERSCIENCE PUB DISEASES PULMONARY DUST , Bk 399 ded res Scattered throughout diseased healthy istant clothing the lung in both the and parts are my 10 persons ex- spindle structures described first by McDonald These bodies are 20 to e e incidenec of 100 a in length and are bulbous on one or both ends so that they club- or appear 0s has however dumbbell They are brownishin color do not stain and give a Prussian- blue reaction foriron Simson has produced these bodiesin guinea pigs by ex- of asbestosis different froin nically it re- exposure to atmosphere containing asbestos Lynch concludes that perimental thesecurious bodies signify exposure to asbestos dust but do not necessarily indicate asbestosis In other words they are more properly referred to as asbestos ut it may be - bodies and not asbestosis bodies 5 right heart - ray examination For an excellent review of roentgenographic findings in nt in persons suspicion as both silicosis and asbestosis the reader might well refer to Pendergrass Char- acteristic differences in the roentgenographic findings in silicosis and asbestosis marked than rexis occurs ogers are apt dominate in ar fibrosis of ! asis and 11 as the posure it is nd that the by grinding p reviously urkan and | by fibers The signifi- ] carance of : is thickenThe alveolar fibrosis be- in its place 3 of fibrosis ar appcar- 50,1 50,1 1935 Jccupationai Fibrosis diffuse ilm may have ground glasg Fibrosis nodular pleural . appearance from involvement ': * - Findings may be either bilateral or uni- _. Findings characteristically bilateral . Losions largely in the lower one half or two thirds of the lung fields Emphysema in upper portion of lung fields Borderline degree difficult to recognize Lesions predominantly in the upper two- -- thirds of the lung fields Emphysema in lower portion of lung fields Borderline degree more easily recognized largely preventing to Control exposure Prevention of asheetosis depends largely on preventing Fo FeOS fege fon < 1 exposure to ContrPolrevention neces- only long fibers cause respirators sary Also Also only sary comfortable The more the uisvast line dust respirators gauze respirators appear to be perfectly adequate filters for the long fibers Up to this time however they have not been approved States by the United Bureau of Mines this purpose ~ Edwards Miller Allowable concentrations Dreessen. Dalla . | and Sayers have found evidence indicate that 5 million particles per cubic foot of air is a satisfactory figure for the maxiinum permissible atmospheric concentra- tion of asbestos to which workers may be exposed Howeyerin setting up this figure only fibers less than 10 ...in length were counted and the longer ones were disregarded It now appears that the shorter fibers have to be disregarded and permissible concentrations of long fibers established which has not been done . The prognosis with early to advanced asbestosis is good pro- vided moderately the inhalation of asbestos fibersis materially decreased Unlike silicosis * #S MeDonald Brit Med J. 2 1025 1927 Loe, ' * W. Simson Brit Med J. 1 885 1925 oe 7, Asbestosis K M. Lynch J. Am Med Assoc 109 1947 1936 E. P. Pendergrass Roentgen Diagnosisin Silicosis and in A. J. Lanza ed Silicosis and Asbestosis Oxford Univ Press New York 1935 - W. C. Dreemen J. M. Dalla T. I. Health Edwards J. W. Miller Pub Bull No. 241 1938 tae ls and R. R. Sayers S. . . . . . . os . wae ek we le Of. COP) eo 4 wore i . saat ae = 4 er . wots siete as B288 B288 FTI 6 . Sere ee Ne eee Caine can af oo: References References ATTACHMENT II : DOCUMENTATION OF TLV FOR 1966 ACGIH so : Henderson 1 Y. Haggard H.W Noxious Gases Reinhold Publishing Co. N.Y. 2 Nau C.A South Med J. 41 341 1948 3 Elkins H.B Chemistry ofIndustrial Toxicology Wiley & Sons N.Y. 1959 4. Bulmer F.M.R. et al J. Ind Hyg & Tox 22 111 1940 co- ASBESTOS ?* mppcf Asbestos is a generic term applying to a number of mineral silicates that are incombustible in air and can be separated into filaments The most widely used in a industry is chrysotile a magnesium silicate from serpentine Other types include amosite an iron magnesium silicate crocidolite a sodium iron silicate tremolite a calcium magnesium silicate and anthophyllite also an iron magnesium silicate Miller and Sayers 1 showed that intraperitoneal injection of amosite chryso- tile and crocidolite in guinea pigs produced the reactioonf an inert dust Vorwald et al 2 confirmed this for short fibers under 3 but observed that long fibers produced a fibrous reaction Continuing unpublished work by Gardner these workers demonstrated that long fibers 20 microns and above produced peribronchiolar fibrosis in lower animals and developed evidence that this resulted from mechanical rather than chemical action Asbestos dust containing 0.6 per cent fibers longer than 10 microns in concentrations of 138 mppcf or 0.8 million long fibers per cu ft was capable of producing experimental asbestosis in guinea pigs When the concentration was 6.7 per cent fibers over 10 microns 40 mppcf equivalent to 2.7 million long - fibers per cu ft the reaction developed in approximately half the time That exposure to asbestos is associated with development of a potentially dis- 2 abling pneumoconiosis in man has been amply demonstrated by industrial experience 3,4,5,6,7,8,9,10,11 The present threshold limit was recommended by Dreessen et 2 al 8 after study of 541 employees in three asbestos textile plants using chryso- tile Only three doubtful cases of pneumoconiosis were found in those exposed to dust concentrations under 5 mppcf whereas numerous marked cases were found above 5 mppcf Counts were from collected samples in ethyl alcohol and dis- tilled water Both fibrous and nonfibrous particles were counted but the latter greatly predominated While chemical analyses of collected samples of borne dust corresponded particulates particulates of to those of by conventional of asbestosis settled dust methods conventional methods because samples it is believed that dust counts of expected TO Ingrace be expected GIVE ONLY the ? relative importance Ingrace measure measure lone mbers References . aes 1. Miller J.H. Sayers R.R Pub Health Rep 56 264 1941 2 Yorwald A.J. Durkan T.M. Pratt P.C Arch Ind Hyg 3 1 1951 3 Merewether E.R.A J. Ind Hyg 12 198-239 1930 Pneumoconiosis Abstracts 4 5 6 7 8 _ Wood M.B. Gloyne S.R Lancet Dec. 22 1934 pp 1383-1385 Fulton W.B. Dooley A. Matthews J.L. Houtz R.L Penn Dept. Labor and Ind Bull 42 1935 Foes Lanza A.J. McConnell W.J. Fehnel J.W Pub Health Rep 50 1 1935 Donnelly .: J. Ind Hyg & Tox 18 222 1936 Dreessen W.C. Dallavalle J.W. Edwards T.I. Miller J.W. Sayers R.R 9 Lynch .: Arch Ind Health 11 185 1955 | 10. Smith K.W Arch Ind Health 12 198 1955 . 11. Cartier .: Arch Ind Health II 204 1955 e cw o ene - he . 2. Loe . oo ANNALS ATTACHMENT III ... ANNALS OF THE NEW YORK SCIENCES oe oo. 132 ART EFFECTS ASBESTOS sgt BIOLOGICAL ACADEMY OF DECEMBER 1965 1965 nade I believe 8 GOO fields were e i would account Me s I also should he number of pson on Section V. Hustan Exposure to Asbestos Dust ControLS AND STANBANDS _.. THE INHALATION OF FIBROUS DUSTS oo *. V. Timbrell Medical mo : . Research Council Pneumoconiosis Research Unit Llandough Hospital Penarth Glam Great Britain Particles are deposited in the respiratory system by the action of four . different mechanisms Do. ne 1 Particles are removed from the inhaled air by settlement under 8 gravity the magnitude of deposition being proportional to particle free falling speed and the time available for sedimentation parte 2 When a change in the direction of air flow occurs particles owing Pere to their inertia tend to continue on their original paths Some may be on deposited in this way on the nasal hairs and the walls of airways The the efficiency of inertial deposition depends on relative magnitudes of ee the drag and inertial forces The magnitude of inertial deposition is thus > falling speed -F proportional to particle _ 3 Particles suspended in the air are under ceaseless bombardment by boh. e molecules which constantly displaces them and may cause their deposi- & gtiaosn on surfaces in the respiratory system Since particle removal by this sies " mechanism is significant only in the small pulmonary air spaces and for canie particles half micron and smaller in size it needs no further con; wade. fourth mechanismsignificant sideration in this paper ns There is a For a compact particle to remain 4 in the air its center must be separated from all surfaces by the wbeeh a sduisstpaenncdeesd greater than the particle radius Deposition occurs when ' ry from a surface reduces to equality with the particle radius The distance increases with magnitude of deposition by this interception effect in airways increase in the ratio of particle size to tube diameter For compact particles 10 microns and smaller in size the effect is of no real significance even in the finest airways which are several hundred microns in diameter compset particles found in numbers in alveoli arcioarcio true even men are show 1997 1997 e microns and smaller in size his - a" Mor CxNUSca LO acrcenis 30 microns and n contrast asbestos concentrations on microns concentrations So concentrations concentrations . asbestos locis AT : and cre ammeer Fw rece mt ... W... e =e eeo-t... cre te to twe hse same deposition mechanisms as compact particles and since mainly re- _ subjected the two mechanisms sedimentation and inertial precipitation sponsible for particle deposition have deposition parameters which are to falling speed an investigation of the relationships pbreotpwoeretniotnhael falling speeds of fibers and their dimensions was clearly , A PATT PATY TY INTERSCIENCE PUB 398 2 SANAD . E SANR DER fireproof resistant bined with cotton and woven as a textile for and wer clothing + and other substances Lanza estimates that there are about 10,000 persons ex- posed to asbestosin the United States Most observers feel that the incidence of asbestosis in American asbestos workersis quite low Asbestosis has however been reported more frequentlyin England and Canada| Lanza McConnell and Feline concluded from their study of asbestosis that prolonged exposure to asbestos dust causes pulmonary fibrosis different from that produced in silicosis and demonstrable by roentgenogram Clinically it re- sembles silicosis in that it is not disabling in the early stages but it may be markedly disabling when advanced and frequently leads to death by right heart failure Although tuberculosis has been shown to be no more prevalent in persons with asbestosis thanin the general population lung cancer is under suspicion as occurring more frequently with asbestosis especiallyin England 7 Symptoms The onset of symptoms of asbestosis as of silicosis is slow although symptoms in advanced cases are apt to be somewhat more marked than in silicosis As in silicosis dyspnea is the cardinal symptom Anorexia occurs frequently in advanced stages and cyanosis and clubbing of the fingers are apt constancy to appear with greater in asbestosis Pathology The fibrosisin asbestosisis diffuse and tends to predominatein the basal portions of the lungsin contrast to the generalized nodular fibrosis of silicosis with a predominance in the upper portions of the lung Bronchiectasis and bronchiolectasis are frequent especially in the more fibrous portions Whereas the proliferation of fibrous tissue is caused by chemical action in silica exposure it is producing exposures induced mechanical action in asbestos almost . wean from to if. de janeris but wat hy har slinivi ge ots, discussedbelow signifi- cance of this finding on prevention of the disease will be ... The Microscopic anatomy Johnstone described the microscopic appearance of the lungs somewhat as follows In the early phases of the disease there is thicken- F land ing of the alveolar septa which results from fibroblastic proliferation The alveolar spaces contain numerous phagocytes With progression of the disease fibrosis be- comes more marked the alveolar structure gradually disappears and in its place there is now dense fibrous tissue The few alveoli that remain in the area of fibrosis . are fined with low cuboidal epithelium giving them an almost glandular appear- A. Lanza J. Am Med Assoc 106 363 1936 ,A. J. Lanza W. McConnell and J. W. Fehnel U. Pub Health Repta 50 1 1935 L. Gardner Ind Med 9 45 1940 A. J. Vorwald Med 1 1951 Experimental studies of asbestosia Arch Ind Hyg and Occupationai Saunders Philadelphia /R /TR. Johnstone Occupational Diseases ? . 1942 - : .. wot > 110 -, "". otete Mtoe THE NEW YORK ACADEMY OF SCIENCES SCIENCES VOL 132 ART 1 DECEMBER 31 1965 + BIOLOGICAL EFFECTS OF ASBESTOS Annals New York Academy of Sciences . ported from guinea pigs and they consist of irregular masses of ferritin granules in which are embedded haphazardly arranged particles of asbestos ' dust together with any other foreign body inclusions present in the macro- phages FIGURE 9 The needlelike particles described in the previous paragraph can be found in these irregular bodies as well as in normal ones In the study of guinea pig axbestos bodies it was reported that segmented bodies were only rarely found and that when they were present they were . formed by the uneven deposition of ferritin material rather than the ero- sion or fracture of a previously smooth layer of body coating In the hu- man material the picture is much more complicated In some cases the segmentation still appears to be produced by uneven ferritin deposition but often the segmentation results from the splitting of a previously smooth coat and does seem to be part of a process by which the asbestos bodies break up . In summary the microscope examination of lung material con- taining asbestos dust has produced the following interesting or promising information Some workers have in the past suggested that only relatively men ae Davi_ material can ace asbestos bodies Although all si has also shown` without becomin same fiber to rea body coating ma and if this is tr coated and that ; is so then further deposition onto as HOLT P. F. & 1. HOLT P. F. Karker H. E. 5. Richter G. IV LINDNER E. 19 i 3 bs 2: . 3 te ad oe . aes ee er y 7 = oe wet ls tos EBSA) el Speen bs, iscpenrer son, AhSpaliong Bega eae a seer ete sree 8 oti ore eae et ie meg ies Seu ETS arrantes ng asinstos dust Preliminary re Tesnits sugeest that it may be inst as ( 1 en os Cree ited en recht tsandaielyaydee oa a _ large and small particies Lae me From these microscope studies it seems that asbestosis is basi- cally an intracellular process and that the alveolar macrophages and their derivatives are the only cells directly involved In conditions of continuous , dust exposure of course there always will be free dust in the alveoli but the animal experiments indicate that all dust will have been phagocytosed within a few weeks of the cessation of dusting There is no reason to suggest that this does not apply to humans as well Indeed in the human biopsy material very little free dust was found although in both cases the enves patients had been exposed to dust to within a few weeks of the biopsy It is therefore the reaction of asbestos dust upon the lung macrophages that 9 needs to be studied if an understanding of the pathogenesis of asbestosis dt th is to be obtained Conversely the reaction of macrophages to asbestos dust 1 is important and in this respect the most obvious reaction is the formation OO of asbestos bodies It was originally thought that only long fiber dust AY became coated but the microscope has shown that the ferritin o- - . - ad 2. en om. wt ae