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The American / Ceramic ' Society , I February 15,1993 I hereby certify that the attached copies of Ceramic Abstracts, Volume 18,1939. are true and accurate copies, which are maintained in the normal course of business at the American Ceramic Society, 735 Ceramic Place, Westerville, Ohio 43081. Christine Schnitzer Product Manager Ceramic Information Center 735 Ceramic Place Westerville, Ohio 43081-8720 . 614*890*4700 TWX: 7101109409 SC-ALL-01750 SCF-ALLF-00555 PLAINTIFF'S h EXHIBIT IWV-024S7 I SC-CER-3752 s /a ( a *> I CERAMIC ABSTRACTS Compiled by ThejAmerican Ceramic Society Volume 18,1939 Ross C. PutfiV, Editor Maily J. Got ) Cmx.Y C. Van Satoiot > AttUtanis Domorav J. Wallace ) CommitU* on Publications: J. D. Sciaxvan, Chairman, W. W. Wixshtf, A. N. Fno#. E. E. MaUaixl It C. PtntDY i I Abtfrectem `J, B. Austin, A. A. Ayaa LXEmetltXX V. "Bartktt.X C. "Sevan, D. A* Biddle, W. H. Bruckner, R Budnikov, J. C Chaston, L. M. Church, W. M. Cohn, M. V. Condoide, P. S* Dear, Maurice Delanfre, R. W. DcviUers, Joseph Ford, W. D. Foster, V, D. Frechette, J. L. GaUsp, J, D. Gat, It A. Grecory, Max Hartcnheim, J, J. Hazel, F. G. Heck, It A, Heindt P, O. HeroM, G. It Hutt, J, F. Hyde, Herbert Insley. C B, Jeanl, B* Z. Kamich, B. E. Kinkulkia, & Hondo, Yosio Kora. Waltber Kttrs, B. B. Lane. V. S. de March!, L. F. May, E. H. McClelland, J. It Noy, J. G. Phillips, Alexis Pincus, M. E. Poor, C. H. Rapp, Katherine Reed, H. K. Richardson, B. C Ruprecht, A. B. Searle* Stanford SetcfaeU, G. R. Shelton. N. M. Shukri, H. E. Simpson, A* ?. Som, E. Sttfanowski, E. W. Steaxel, A. G. Stem. Joseph Stewart, B. H. Strom, L*. Ij. Thiess, Rans Thumaner, F. V. Tooley, E. J. Vachuska, F. E. Vaerewyck, F. J. Zvanut. Editorial Office: 2525 North Hish Street, Columbus, Ohio . Publication Office; 20th and Northampton Streets, Easton, Pa. *7, 18. No. 1939 General i&cauon v*tif*tion of aluminum du*i a* a po&ufik' rv*frfarory liness Iclehnlinexs of work ptuev*. buddy deanlxiMeut, and fOCtSJ CO4 wjyafA resulted from the appearance in 1034 at the Oc- general hygiene), and (6) reduction of manual operations. substaatii ItspaijonaJ Disease Clinic. Berlin, of a patient who had been > consists pr*yinf aluminum bronze for nearly a yeas aod who H.JLS. Preventive * measures in the uee of crystalline silica. uiuTa wowed signs of a Jung disease of a not very dear character, M.2d. Shave*. Jnd. Med., 7 |8) 472-73 (1938).--S. pre fenric cos] r^rly in 1934 an Italian doctor of the throat and nose sents the subject systematically under three major as * provide -4mc *t the University of Rome published hit observa pects: (A) medical, () engineering, and (C) managerial. *A. to tfcl tions upon the effect of aluminum dust on the air passages. He suggests that, before any protective measures in the ' predpitaa The present research includes (1) the components aod use of crystalline silica arc resorted to. the fact be estab properties of the substance (which docs not occur in aa- lished that a silica hazard exists. Data involved Include 1st. c.a *ure in metallic form but is the result of mechanical and (1) a definite exposure to dust known to contain a certain 1.718. Sep? chemical processes), (2) 30 dialions of previous stndies on percentage of silica and (2) sufficient dust exposure, as ini a staU Oie injurious effects derived from the preparation of estimated by dust count and dust composition, to cause preparing] aluminum and its industrial uses, (3) the- detailed case* silicosis if the exposure Is continued over a sufficiently ^ molccuh history of the patient, with laboratory findings and Roeat* ' long period of time. In emphasizing (), S states that *n of fiUoai studies. (4) an intensive investigation of TO workers it is entirely the problem of the engineer to prevent silico sufficient t jn aluminum works, and (5) a critical analysis of the sis. The medical director can only cheek the adequacy of tion of sub Italian data. The hazards were found to be completely the engineer's methods of' control. RJL it tempo* negative, both in the processes of making aluminum and Recovery metabolism of silicotic*. A, B6hme. Arch. :h to tram irom inhalation of the dust. K.R. Gewerbepalh. of Cctoerbehvz., 3, 602*10 (1938),*--B. re h substaof tahalttion of dust and control of dust hazards, W. C. cords the metabolism studies and muscular tests applied / JaMXS. Concrete, Cement Mitt Ed., 46, 200-201, 216-17 193S).--Many persons inhale excessive dust Into their to $2ieotics in varying stages of the disease to improve their greatly impaired respiratory capacity and muscular lungs, with coal and iron-ore dust coloring the lung (issue, action, if possible, and at least to record the success or in most cam, however, these changes are of no more im failure of such efforts. Tables show a comparison of the portance than callouses on the hands. Only two dusts metabolism of normal persons after 15 bendings of the actually cause diseases on inhalation, silicon dioxide (us knees (as In climbing stairs), after taking food, and after 37. Akoh ually quartz) and asbestos. Only particles below 10 m rest with the metabolism of the silicotic* (four having a iilieosb de are effective, and these must be breathed in high concen lessened industrial capadty oi 80% and six lessened to 50 ieuts man tration aod over a long period of time. A sale maximum or 60% capacity). Items tabulated include age and vital * inhalation concentration is 5 million particles of quartz dust per cu. capacity after food and after rest; respiration, minute and cUnica ft. The exposure of each man should be reduced to volume, and 0% requirement; the respiratory quotient, of artificial particle-hours to be comparable. The length of time conversion rise in %, and these values after rest; and the <s sot coo necessary to develop silicosis is controlled by (1) con Os needs (ce.Anio.). In the severest forms of silicosis, the of riUcosu centration of dust, (2) proportion of free silica, (3) length total variation in the 10-mia. recovery periods was higher ed. rd exposure, and (4) general health of the employee. It than the highest shown in normal persons. Add b MJI. is unusual to have silicosis develop in lea than seven years. sorptioo had not returned to normal after 10 min., while iciency tnJ Dust should be removed at the source. Vf.Uf. in normal persons It was completed in 3 or, at most, 6 min. Occupational diseases of the lungs In agricultural work The minute values of respiration In the most severely SI Abated bj ers. Richard Fawcttt. Brit. Jottr. Radiol., -11, 378-82 subjects was markedly raised after the work attempted, mg system June, 193S).--In 1836, 748,700 persons were employed in and even after the 10 min. rest, it did not attain Its pre 1 conveyers, the agriculture of Great Britain, forming one of the largest vious value. The higher the lessened capacity for work :g extensm working groups. F., as a country practitioner la the In percentage value, the more the records varied in severe < of the old hills of the Lake District, early became familiar with the silicosis. Experiments on early or middle-period sili material u agricultural types of asthma, bronchitis, and pneumonia cotic* showed fewer certain, unmistakable results, their wo or three which usually ran a protracted course among these workers; working capadty being still much higher. ICR. H.E.S. -ccovtry, when occurring, appeared largely due to poias- Research laboratories of Mellon Institute. Harry S. . r. 5. pa. *iutn iodide and creosote administration. The infections Coleman. Jnd. ng. Chent., Anal. Ed., 10 (9] 550-5$ * irtide. rep-l ;hc working people are subject to are listed as organic (1938).--The design, construction, and equipment of the ft reJectm! matter (microfu&gi. and bacteria) existing in grasses, research laboratories in the new Mellon Institute building re material! >iraw. grain, fruits, the soil, and in ihe excreta of farm arc described in detail. Illustrated. - F.G.H. tative docu>{ animals; only occasionally does inorganic matter affect Research laboratory of the Columbia Chemical Division ro1 has them. r.-., men carting siliceous stones. The details of of the Pittsburgh Plate Gloss Co. AHOK. Jnd. Ent. Jeatiag with1 fungi infection and the procedure In Identification are Chem., Anal. Ed.. 10 (8J 329-30 (1938).--The physical neasuresartj briefly aod clearly given; types of fungi predominantly equipment is briefly described. Illustrated. F.GJH. resourceful- zffccdng six special groups of lann hands, *.g., bay or gTun Safety-aad2ij:giA in the foundry: X, Medical aspects. ibed. Stress workers, stablemen, gardeners, etc., are described, with R. R. Jones. Trane. Amer. Toundrymtn'i 8 12) miendcd tel -.he resulting symptoms and Injury- Nine points to be 534-64 (1937).--The more Important industrial health by lengthen i\midcred hi a doctor's study of such cases are systemat* problems associated with the foundry industry are those xammatiomi cully presented for case-history record. Special com- related to (a) general physical characteristics of the budd to aBotr the] r.u-m is made upon the agricultural groups, with citations ing. (3) housekeeping practices, (r) drinking water supply out process.! Vrtm case reports; 13 largc-sixc radiographic rcproduc* and lunchroom and toilet facilities, (d) exposure to extreme KJL ins of chest phenomena in the various fungi invasions temperatures, (c) exposure to toxic or irritating dust, .IX Seeds, * *neenicd are interpreted for the lay reader. F. emphasizes fumes, and gases, and {/} medical supervision. Success in ibcusses the | hir*t occupational diseases as rare, seldom reaching radio* the control of industrial health hazards b primarily de lies and the Kirical departments or diagnosis.* Yet common micro- pendent upon the employer's attitude toward the problem. with such angi. often innocuous, do become pathogenic under cer* Discussion. J. A. Barrro.v it al. Ibid., pp. 576-83. ay minerals :ui& conditions. The incidence of harmful infection b H.E.S. er increased mure common and more widespread than n generally Hermann August Seger. Akon*. Bull. Amer. Ceram. Ibid.* 155811 rvaUsed, 19 references. K.R. Sac.. 17 (11 ] 403-64 (193$). id shapes b Practical significance of silicxtt research. A. Dirnsu Silicate research and engineering. W, Eitel. Z. IV. iu*h Patent u-cwA. Ber., 14 (51 101-64 (1930). J.F.H. Dent. Inf., SO (2 ) 37-41 (1930).--The conditions and Process /of Prevention of disease In industry. D. Hunts*. Ind. status of silicate research as carried out in the Raiser the Hke of v fcr**uri, 13,134-36 (1937).--Thu main principles underly Wilhelm Institute In Berlin with regard to glass, ceramics, RJLH. ing the prevention of disease in industry are (1) protection cements, mortars, and concrete and the relation to ap n. especially workmen by law such as workmen's compensation acts. plication in practical engineering are explained. M.&. . .Grxcr'othyi^ - medical inspection under stale support, (3) education Silicosis among grinders. J. L. A. Grout. Bril. -vprougb io* *' 10 'be nature of iht* danger. 14t importance of clean Jottr, RadiM., W. 31*6-70 (June. 1938V--This interesting i -t S No. 2 IWP General 63 i and nr*' -^jne labor limit in the German hard-coal industry for ous hi regard to the health of the employees. Data . II the 47 atmospheric localities, is an arbitrary limit. In obtained during a four-year survey are as follows: ion. the? jcte far au ceoeraJ. working capacity seems to be lowered by high temperatures to 00% values. The physiological reactions YH tpmr* So. Hipliym SUkttS* t%) however, *s arc re- of men continually wary when climatic conditions grow constantly worse. Injury to health from dry and high 1-3 6-10 1174 812 * 0.5 3 ben and temperatures alw* can not be definitely established* the 11*15 602 5 io pbot-; relation to humidity present always being a factor. Omit* 16-20 532 10 I having: ' ttsg the beat factor, a humidity of 25* seems endurable, .a single, la regard to the elimination by the akin or lungs under *21-25 20-30 385 15 2G8 22 ne points high tad humid conditions, results appear personal and 31-40 215 21 surfaces* individual. Greater water elimination occurs (a men 41-50 47 . 21 . Debye the form c X-rays t lengths c length, diffracted that they the pria~ a on the .* formed. | acclimated to hot humid air than in those not inured. Men habitually rather than occasionally at work climi* sate larger quantities of staler. Rising temperatures m a dry climate and rise in humidity increase elimination of. tracer through the skin. Individuals showed, ht their dlminatios through the skin, none of the expected cor* rtspondences which might be traced back to these chang* log environal states. In this investigation, bodily tem* perscures generally rose very little proportionally under higher outside temperatures sod increased humidity. From this data, S. concludes that simple sQicosb as seta in foundry workers is only very slowly progressive, so much to that no visible changes appeared in four years observa tions, and is only rarely sufficiently advanced to cause symptoms and Incapacity for work. Control of the foundry hazard Is best accomplished by elimination at Us source of the dust generated by sandblasting, sand chip ping, sand grinding, and shake-opt operations. Ftv* employment and periodic examinations are essential to Jieroeot- I Blood pressure, respiratory frequency, and pulse frequency prevent tubercular individuals from carrying on a dusty ` made in., ! showed no quaotiutive relation to selected climatic con* trade and to discover new infeetfoo and reactivation cases xambung; \ diuons. Fourteen diagrams and two tables are given. .jn where, 1 Id references. K JL /way that : diagram, Dust content in an asbestosis lung and the behavior of the so-called asbestosis bodies. X. Svantes akp A. as they arise. * 3.CJL Selenium as a potential Industrial hazard. H. C. Dudliy, U. S. Pul. Health Rifts* S3 (81 281-92 (2933). --D. points out those industries which may have un ter inter-' i Bycock. Arch. Gmrbipath. fr.Ctarerhekyf., 8V 26-70 recognized hazards due to the possession of selenium* ( Debye* (1937-1938).--This research upon the effects of asbestos beanog materials. Increasing uses and applications of the d by re ts turned* dust when breathed in by industrial workers In asbestos clement and Us compounds necessitate the warning that was carried out by the State Geologist and the State in certain combinations selenium Is toxic. Hence, in ' the tiny- Chemist of the Swedish Geological Survey. They indi* dustrial plants where these substances are utilized wfll of curved* cate the differences between the asbestosis lung and the need to afford their workers adequate protection. Sele . Hoetst* . sQicotic. the former being due to the action of a basic nium is obtained as a by-product from electrolytic refining boratones. riheate (isotropic), accumulating hi yellowish or reddish* of copper; this b the chief commercial source. Xu first 16 (1)33 brown needle-like masses, and the silicotic being due to use was largely confined to the glass and ceramic industries, U.V.G. f quarts (SiOr) degenerative action, exhibited in nodutes where It was used as a glass decolorizer and for the pro sad other quite different manifestations. Asbestosis duction of red glass and glazes. Rubber manufacturers was first identified In 1006 by an English physician. next made heavy demands on domestic copper refineries: ed. "On Montague Murray, of the English Compensation Com* recent Increased uses have not only exhausted domestic . Leiprit .47 15551 refidiied; mitre* of Industrial Diseases. The chief mearch studies supplies but have required importation (a larger and since that time art reviewed by these authors in their larger quantities. The ceramic industry alone has cumulative value. Their own procedure In isolating utilized more than 170,000 lb. According to D,, sew . >f ceramic asbestos dust and its accompanying "asbestosis bodies" sources of supply will have to be opened. The occur chemical by treating the affected lung substance with hydrogen rence and location in 21 states of 15 minerals, with the are men* peroxide, also by purely mechanical action upon a "heavy** selenium parts per million, are tabulated. The selenium ; booh b folution. is given together with the ascertained percentage content of the earth's crust has been approximated at ILA.H. values derived chemically from the eight or more mineral 0.005%; nearly all sulfur and sulfide deposits contain it: components of asbestos. For the entire lung, approxima certain westers phosphate rocks show amounts of even 55 tions were 5.6 g, asbestos bodies, 0.3 free asbestos needles, parts to the tsiUton. In a targe number of soil samples materials, and 1.4 tout asbestos content. Total dust respired by the taken from areas surrounding smelters near Butte and lxing Co.y. riven lung was about 2-S g. Some of the bodies bunt up Anaconda, Mont., Kenaet, Calif., and Copper Kill, Tean.,' in needle form were composed of titanium oxide tTtOO- selenium was found: it decreased in quasiiuty with a jffieate*^ Intensive study and analysis of the coverings of the bodies distance from the smelter. Extensive animal experimenta A P*KH- Hem to indicate that they are'btood derivatives after tion by ingesting selenium compounds -shows that such V. 9. 193S the mineral has entered the lung. The fibrosis ultimately' substances, when soluble, have toxic effects, both acute . and generally distributed through the lung following the' and chronic. Early cellular destruction occurs in the cCcUOGB dust inhalations appears to have definite relation to the liver, with later pathological characteristic changes 2.137.058. presence of the asbestos needles and their movements throu ghout the organism. Guinea pip experienced about the lung under the mechanical stimulation due to severe metamorphoses in the liver and, after inhalation respiratory movements. 12 photomicrographs. KJL of hydrogen selenide, hypertrophy of the spleen. Men . Heinrich Hies. Axojc. Suit. Amer. Ceram* See* 17 employed in copper refineries which extract or purify :12; 4PCM*] (1938). selenium display the symptoms, respiratory sad gastric, t History of gtsss industry at Hew York World's Fair* which characterize metal poisoning generally. The with high Anox. Suit. Amtr. Ceram. St*.: 17 (121489 (1938). excretion of selenium In the urine, however, is conclusive -ch. Cewer- Hygienic dangers of nonferrous metals. H. Bgeese. evidence of selenium absorption by workers, D. gives be authors Je&tteirttchajl, 17 (32] SU'Hi* (1933).--B. discusses the in detail the procedure for urinalysis in detecting and uc to high dangers in handling Pb, Hg. 2n. Cd. As. Yb. Se. Te, Cr. estimating selenium in the urine. In the tabulation of ueb as are At Cu. Mn, light metals, XT, Tl, and Os due to inhalation of industries with possible selenium hazards, the glass and water<oo- du>i or vapors or contact with each individual metal and ceramic industries are in the secondaty group, Li* they conditions. "Wen* for eliminating or at least minimising the risk. utilize selenium and its compounds as basic materials in . high tern* , M.H. manufacturing processes. The immediate sources of - as such b lung findings In foundry workers. O. A. Sakpcx. hazards involved in this group are given as melting pots *>) decrease Amtr, Jnnr. Pub. Health, 28, 60l-Ti( (1P3S).--Of the and furnaces, the fumes of Se and SeO* being given off. condition) various occupations in foundries, sandblasting is the most The sampling of vapors and gaseous constituents of in `:-*vr. so that w a fufl- aprriuu* if done wit (unit proicctiou; otherwise sand dustrial plant atmospheres and contaminations of labora pipping anrt grinding of large castings arc the most danger- tory workrooms is explained in dcuil in connection with - l  4* * J.%W7% %* *' * iw^**i, i 10S Ceramic Abstract! VoL IS. No. >5 tests mad indicating just bow closely the sampling W* mats die me character of a batch of material being tested* F.P.F. Volumetric aaalyri* of copper. M. Seem and Y* YaUaxOTO. Jour. Sot. Ciom. fdw Japan, 41 [2| 348 (1033).^-Copper can be reduced to the cuprous ion in an solution with sodium sulfite. This cuprous ton can be titrated with potassium permanganate solutioa. After the reductioa is complete, the solutioa is acidified to expel the excess sulfur dioxide da An additioa of s small amount of chlorine ton in the form of sodium chloride b necessary to avoid the precipitation of cuprous oxide. The sample of solutioa conaiaiat about 0.18 |. of copper should be treated as follows: pour the test solutioa into a 500-cc. &uk. dissolve U in a small amount of water, and make it slightly *ctd. either with uttfunc add or sodium hydroxide solutioa: add 50 cc. of 10% solution of sodium sulfite and 6 cc. of 10% solution of sodium chloride: boil mod rtdlssolve the yellow precipitate in the dark (double salt of cuprous sulfite sad sodium sulfite) and make the solution colorless; add 60 cc. hot sulfuric acid (prepared at this time by mixing "JO cc. of *U> .Y sulfur.* acid and 30 cc. of ri .V sulfuric acid). The white pr*. cipitate of cuprous chloride is formed, and sulfur dioxide gas ts expelled violently. Boiling is continued for 16 u 211 min. to expel sulfur dioxide gas completely and to exp> excess hydrogen chloride. To fill the dash with catbo* dioxide. SO cc. of 3% sodium carbonate solutioa are added Keating is discontinued and the solutioa is titrated wi:* i/ti> jY potassium permanganate solutioa which contain* about 3% sodium carbonate. The presence uf fh*. $n`"\ Ma'. etc., has no effect; therefore, no preliminary separt- tioa of these tnetaU is needed. ^LWC. PATENTS Making alkali mstal silicates. 0. R. McD.\xtr. Diamond Alkali Co.). V. 5. 2.15X372. April U. m> March T. 1935), Production of polysiUestea Dzssavx Fils. Fr. 5-V - 732. Oct. 3. 1937; 66 (t9J 173 (1939). D.A.3. General Air conditioning in industry: L W. U fuusu. A. between liquids' and gases, as it presents the gascoc* . SrACgr, F. C HoccfttaN, an 5L B. Ftxpeancn. reactant In the form of minute bubbles, thus giving & Beating Pipint fir Air CandUtonine, IX [2| 107-11 maximum surface for reaction. (2) Biscuit porcelain It (1939).--This study was conducted in the research labora used us filtering operations where it is necessary to reps* tory of the American Society of Keating and Vencaadng rate extremely minute particles from acidic or ocher cor Engineers at the Pittsburgh Experiment Station of the rosive liquors. It resembles porcelain in color and cos* V. S. Bureau of Mines, The physiological.reactions of position, but differs from it la that it b highly porous, ft men while carrying on tight work in atmospheric condi pore dimension can be regulated in size from 16 mtcroa tions including effective temperatures from 77? to 92*P down to below l micron. The 'nature of its ingrediaso with relative humidities of 60. 73. and 90% were lures* * and the temperature at which it ts fired ensure resistaa:* tfcated. The history of previous investigations is dealt to adds by the more siliceous bodies or to caustic alkaci with. Two charts. JX.G. (where the alumina content predominates). Bisect J Appearance end prevention of sQIcosU and asbeafesb. porcelain b also used for electrolytic processes is & E.vmco C Viguanl. Pats. AM. Applicant Ltoaro filtration of oils and concentration of rubber latex. LuL. 9, 387-94 (1938); Chem. Ats^ 66, (1939).--A Diatotnaceous or kieselgubr bodies, while less ramie review Is siren. to corrosive chemicals than either biscuit porcelain J Asbestos!*. R* R. Savxxs am* W. C. Deskssn. Amor. quartzite, combine small pore size with high ptrmab&? Jour, Pub. Health, ** (3| 306 (1939).--to a study of the . and are used for the filtration of neutral, or nearly Qtutrx. North Carolina textile mills using asbestos fiber, a hy liquids. They are usually employed in the form of cacdV drated magnesium silicate containing no quarts, pul or hollow cylinders of small otiameter, elated st one tcc monary asbestos!* was the principal defect found. Ex- or with both ends open, up to a length of 12 in. A.3-5. Ksupet ranged from 0.10 to 78 mtUioa partides/cu. fn Floors for industrial purposes, R. Fitzxac&xck ax? rsoos exposed, from 5 to 10 years to dust concentrations F. M. Lca. Read before Inst. Cbem. Eng. and lei: exceeding 3 ttullioo partides/cu. ft. showed definite Struct. Eng., London, Jan., 1939: abstracted in evidence of asbestos**. Deta so far obtained indicate Trad* Jour,. 104, 79-80. U2 (1939). LJLB that 6 million partides/cu. ft. ts the maximum safe Industrial Impairment of health and poisoning in tb* concentration. * B.CJL metal*workiau industry. . FtfiTAO. Oboe_ fl&cfaaech,. 1* Ceramic filters. Anon. Obm. Ay (London4. 40. (41 35-38 (1939).--F. discusses the danger of silicosis a 46 (1939).--A new range of porous ceramic filtering mate men working with sandblasting. 'Poisoning by nitmu rials has been Introduced by a Glasgow firm. These gases In pickling, etching, and coloring processes, by C* ceramic materials are resistant to corrosive fluids and ere salts hi Cr plating, by Pb ia Pb welding, by CO in exf* made with a pore sire ranging from below one micron up acetylene welding, and by toxic gnus developed in ni^I* to several hundred microns, the distribution of pores and isg and hardening processes is also discussed. 6LK- pore density being exactly regulated. The materials are Life sad' work of Keory LeChatetier (1650-1966). ' produced kt a great variety of shapes--they can bd PASCAL. Bull. Soc. Chim, Atom., (8) 4 110) 1567-Wj sawed, cut. or ground to suit individual requirements-- (1937); see Bull. Amor. Coram, Soc.. 16 (4l 165-W (19*5- and their mechanical strength and durability are very Ceram. Abo.. Id 10} 318-22 (1937). 0.A-5. high. The materials, quartzite, biscuit porcelain, and dbtomaceous or kieselgubr bodies, are described as fol lows: (1) Quartzite filters in the form of square or circular tils, of different thicknesses and sires, and hollow PATXNTS . Rspairing esasnt for ceramic objects. E. Roscxtnc . cylinders from 2 in. (o 8 1a. in diameter and up to 24 in. Brit. 500.576. Feb. 22. 1939 (Aug. 12.1937). , long are produced in several grades, varying from coarse* Satin whit* pigment and proctsa of making. L * ; granted bodies of extreme permeability down to a dose* Wbue. U. S. 2.U5.149. /,a. 24.1939 (Feb. 4.1933). grained type with a pore size as tow as 10 microns but of process comprises treating finely divided day with ' such high pore density that it ensures rapid permeability. add. producing thereby a solution containing alumina*' * The* high rates of dow obtainable with there filters are sulfate together with coloring impurities and an tnso*c: * t exemplified by tire F2T grade which gives a flow of 1700 day residue, removing coloring ingredients from the ^ ; gaU"oins of water/sq. ft./hr. at 6 tb. pressure. Quartzite tion. and reacting the so-purified solution with hydn** \ filteras ai re particularly suitable for industrial filtering and time in the presence of the day residue. * aerating operations of liquids and gases, especially where Ttia for use Us sewage filters. J. E. TcCKta. resistance to corrosive fluids is essentia) and ia reactions 30M78, Feb. 22. 1939 (bepr. IS. 1937), t SC-ALL-01780 SCF-FA-0650 H Mar., 1939 der the conditions >se fluid toxoid, 2 at 3 week interval cipitated toxoid, 3 at 3 week interval precipitated toxoid NCES n, A. H., and Havens D (June), 1932. ' ee, L. R,, and Gill, D q )( 1933. ' )ern, K. C. Canad. 935. ' >. & Clin. Med., 22:893 Roy. Soc. Med., 30:7i :r, D. T., McKinnon, New York Acad. Med,, 1 . R R lcian Ion, England it, yet generously of others. Liberal brethren but ever o the public, admiration of so illectual excellence nd to extend to the salutary inving example can is monument has )ublic subscription . A.D. 1837." si m Vol. 29 Asbestosis* R. R. SAYERS, M.D., F.A.P.H.A., and W. C. DREESSEN, M.D. Senior Surgeon, and Passed Assistant Surgeon, U. S. Public Health Service, Washington, D. C. ASBESTOS is well adapted for use pathological report on asbestosis pub as a textile material because of lished in the United States, and in the its fibrous nature. On account of thiss,ame year, 1930, Lynch and Smith7 as well as its non-combustible and ex reported on asbestosis bodies found in cellent insulating properties, it has come the sputum of asbestos workers. to be used in ever increasing quantities The Public Health Service was re during the past 20 years. Hence, it quested by the State Board of Health is not surprising that Gloyne and Mere- and the Industrial Commission (Ad wether 1 should refer to pulmonary ministrator of the Workmen's Compen asbestosis as a " modern disease." sation Act) of North Carolina to assist The first record of a case of asbesto them in making an engineering and sis seems to have been made by Monta medical study of the health hazards gue Murray in 1900. The first com in the asbestos textile industry of that plete description of the disease and of state. The objectives of this study the " curious bodies " seen in lung were: tissue and sputum appeared in 1927 when Cooke 2 and McDonald 3 reported 2 cases of asbestosis and listed their reasons for believing that asbestosis bodies originate from asbestos fibers that reach the lungs. Their papers aroused general interest in the subject and numerous others appeared soon afterward. Hoffman 4 appears to have 1. To make a medical study of the effects of long-continued inhalation of asbestos dust on the human body. 2. To identify- the manufacturing processes that create dust,* and to recommend practices for reducing the dust exposure of workers. 3. To find out what concentrations of as bestos dust can be tolerated without injury. It is the purpose of this paper to review briefly the principal findings of this study.8 been the first American to call atten tion to the magnitude of the asbestosis problem. In 1918 he reported that 13 deaths from asbestosis had occurred among asbestos textile workers, and about the same time Pancoast, Miller, and Landis5 reported on 17 cases of asbestosis. Mills's 6 paper was the first ENGINEERING FINDINGS The main asbestos raw material used for textiles is Canadian chrysotile, which is a hydrated magnesium silicate containing no quartz. The textile manipulations of asbestos are very similar to the production of cotton or woolen goods. The crude * Read before the Industrial Hygiene Section of the American Public Health Association at the Sixtyseventh Annual Meeting in Kansas City, Mo., October . 1938. fiber is sent first to the preparation de partment, then, in the order named, to the carding machines, spinning frames, winding bobbins, twisting ma- [205] Figure I--Photomicrographs of Lung Sections Showing the Presence of Nodular Fibrosis and Emphysema in a Silicotic Lung and Diffuse Fibrosis and Emphysema in an Asbestotic Lung. A Section of a Normal Lung Is Shown for Comparison. Magnification 16 X. Vol. 29 Asbestosis 207 Table I 0t Results Showing the Exposure of Asbestos Textile Workers Under Controlled and Uncontrolled Working Conditions Equipment Willowing (opening) Piling t Picking Carding (primary) Carding (roving) Spooling Weaving (broadloom) Brusher calenderer Number of Duct Connections *2 1 3 3 4 11 2 3 Volume of Air Handled (CFM) 625-1,000 1,025 2,570 1,420 \ 1,440 j 46.5 1,300 1,650 * Equipped with pneumatic conveyor, t Exhausted bin or compartment. t Individual cone for each spool and connected to exhaust manifold. Dust Con centration With Exhaust (MPPCF) 3.6 2.0 6.7 2.0 2.9 .7 1.0 Dust Con centration Without Exhaust ll;l-36.0 5.4 34.3-74.3 72.3 13.1 4.7-49.7 11.1 chines, spooling frames, and finally to the looms and miscellaneous fabricat ing devices. In all, 242 dust counts were made in estimating the exposure of these asbestos workers. Only summary en gineering findings, or dust concentra tions as they relate to medical find ings, will be discussed. Summarized results of dust concentrations under controlled and uncontrolled conditions appear in Table I. It will be noted that 74.3 million particles per cubic foot (m.p.p.c.f.) is the maximum concen tration of dust encountered. Even this maximum figure is much lower than is frequently encountered in other silice ous trades where it has not been un common to encounter maximum dust concentrations of 1,000 m.p.p.c.f. The dust in asbestos plants is made up of particulate matter and fibers. The median size in microns of particu late matter ranged from 1.85 to 2.40. Particles were smallest in the carding and preparation processes, and largest in weaving. The median length of fibers in microns ranged from 7 to 16.3. As might be expected, the long est (400 fi.) were noted in case of weav ing and the shortest in preparation. Table II Median Length of Fibers Sampled With an Owens Jet Apparatus Activity Median Length of Fibers in Microns Willowing Picking Carding Twisting Weaving (broadloom) 7.0 9.5 8.8 12.8 16.3 Table III Size Frequency Distribution of Particulate Dust Suspended in the Air of Asbestos Textile Plants Percentage Frequency of Each Particle Size Group (in Microns) A Nature of Process Where Sample Was Taken Preparation Carding Mule spinning Twisting Weaving (broadcloth) Weaving (tape) Median Geometric Size (in Standard Microns) Deviation 1.85 1.35 1.80 1,22 1.55 2.40 1.56 1.57 1.33 1.74 1.31 1.64 0 0.5 1 to to to 0.49 0.99 1.49 3 21 37 1 9 24 0 1 25 5 30 24 1 4 43 0 3 11 1.5 2 to to 1.99 2.49 22 10 25 9 38 28 14 9 27 10 24 14 2.5 3 3.5 to to to 2.99 3.49 3.99 42 1 16 4 5 41 1 545 323 12 7 13 4 to 4.49 0 1 1 0 4 7 4.5 5 to or 4.99 More Total 0 0 100 3 3 100 0 1 100 1 100 0 100 3 6 100 208 American Journal of Public Health Mar., 1939 The significance of dust concentra tions and physical characteristics of these air contaminants will be referred to in the course of subsequent discussion. The workers who were found par ticularly liable to develop severe forms of asbestosis were the willowers, pick ers, carders, mule and ring spinners, twisters, and cloth weavers. Their ex posure was found to be as follows: Dust concentration MPPCF Willowers............................. Pickermen............................ Carders and tenders.......... Mule spinners..................... Ring spinners..................... Twisters............................... Cloth weavers Dry................................... Wet................................... 11.1-36.0 34.3-74.3 29.1 2.6- 7.9 3.2- 8.3 3.2-13.2 4.7-49.7 4.7-11.1 MEDICAL FINDINGS . Medical examinations were made of 541 men and women representing prac tically all the employees at the time of study. Five-sixths of them were native born Americans of Anglo-Saxon stock and the remainder were Negro males. The three factories studied had been in operation from 6 to 16 years. About 15 months before the study, approxi mately 150 workers were replaced by new ones with little or no asbestos ex perience. As a consequence, there was an abnormally large percentage of work ers with less than 5 years7 employment in the asbestos textile industry and an abnormally small percentage who had worked 10 years or more in the indus try. More than 200 had worked at comparable occupations in cotton or woolen textile plants, but exposures to pneumoconiosis producing dusts were inconsequential. Characteristics of asbestosis--Pulmo nary asbestosis was the principal physi cal defect found on examining the 541 persons. This disease, a form of pneumoconiosis caused by long con tinued inhalation of asbestos dust, is characterized pathologically by diffuse interstitial pulmonary fibrosis and the presence of asbestosis bodies in the lungs. Clinically, the chief symptoms are progressive dyspnea, variable cough^ substernal chest pain, blood streaked sputum, decreased chest expansion emaciation, weakness, clubbed fingers or curved nails. Late in the disease, the dyspnea becomes distressing, cyanosis may occur, and. there may be severe paroxyms of coughing productive of tenacious sputum. The characteristic chest X-ray shows granular or ground glass markings with more or less obliteration of usual linear pulmonic markings, localized in mid-lung and bases. The grainy appearance may become quite generalized with evi dence of emphysema usually in the apices. Nodular or nodulo-conglomerate shadows of silicosis are not observed, but whether this is due to a peculiarity of asbestos dust or to rare occurrence of extremely high dust exposures, it is impossible to say. Shag giness of the heart shadow is not in frequently observed and seems to be most common in workers exposed to a high proportion of fiber (e.g., twisting, broadcloth weaving). By fluoroscopy, diminished excursion of diaphragm is seen. Peaking deformities of dia phragm, however, occur less frequently than in silicosis. Asbestosis bodies found in the lungs and sputum are characteristic. There is good evidence that these bodies origi nate as a cellular response to inhaled fibers.9 Asbestosis bodies consist of a core of asbestos fiber surrounded by iron-containing protein deposits. They are golden yellow in color, and do not stain with ordinary histologic stains but become brilliant blue when treated with potassium ferrocyanide.. They are variable in form and size and charac teristically are slender, elongated, seg mented structures with bulbous ends which give them a dumbbell or drum- Voi 29 Asbestosis' 209 Figure II--Photomicrographs of Asbestosis Bodies Found in Sputum. Enlarged 530 Times (Except E, Which Is Enlarged 310 Times). A Scale, Ruled in Units of 50 Microns, Has Been Drawn Beside Each Asbestosis Body. Stick shape (Figure II). Occasionally a forked or Y-shaped body is observed. They range from 10 to 180 jx in length, averaging about 35 fx. It has been suggested that damage to the lungs occurs while the body is being formed, but once the body is formed the fiber in the core is rendered inert by its coating of iron.10 The find ing in the sputum of clumped asbes tosis bodies in radial pattern or rosette (Figure II E), which is common in lung sections, has been suggested by Stewart, Tattersall, and Haddow11 as a clear indication of disintegration of lung tissue whether by a process of simple suppurative broncho-pneumonia, or as a result of secondary tuberculous infec tion. In either case, they feel that it strongly indicates a definite underlying asbestosis. On single sputum specimen analysis age age age 210 American Journal of Public Health Mar., 1939 50-59 40-49 30-39 20-29 UNDER 2 0 0 10 20 30 40 50 60 70 80 90 100 PERCENT KAOLIN I______ t______ i______ .______ i______ i______ i______ i---------- 1---------- 1----------- ' O 10 20 30 40 50 60 70 80 90 100 PERCENT ASBESTOS 50 - 59 40-49 30-39 20-29 UNDER 20 O J---------- 1..... . -- .1_!------- 1---------- 1______ L 10 20 30 40 50 60 70 80 90 100 PERCENT SECOND DEGREE GROUND GLASS FIRST DEGREE GROUND GLASS SECOND DEGREE LINEAR FIRST DEGREE LINEAR Figure III--Percentage of Males, Classified by Age, Who Had Certain Lung-Field Markings; 229 Men Had No Previous Industrial Dust Exposure, 80 Had Been Exposed to Kaolin Dust, and 357 Had Been Exposed to Asbestos Dust. Vol. 29 Asbestosis 211 of each case, the incidence of asbestosis bodies increased with increasing dust exposure. They were found in sputum of 46.9 per cent persons whose condition was diagnosed as asbestosis, whereas 24 3 per cent of essentially normal as bestos-exposed persons had bodies in the sputum. They were not observed in any of the persons surveyed with less than 3 months' exposure. Since they may be found in the sputum be fore significant fibrotic changes have occurred, their presence is interpreted as merely showing evidence of exposure. X-ray interpretations--During the de velopment of a typical pneumoconiosis, the lung field appearances of chest roentgenograms pass through a series of rather well defined phases. Begin ning with the normal adult film with its linear pulmonic markings, the first next appreciable change is an exaggera tion of these markings. Then a ground glass or granular appearance is noted which gradually obliterates the linear markings, followed by nodular and nodulo-conglomerate markings. The lung field appearances in asbestosis do not appear to proceed beyond the ground glass or granular phase. Classification of all films was made according to phases. The apparent small amount of involvement of lungs makes it diffi cult to evaluate the severity of the case from an X-ray film only. The difficul ties of interpretation of the chest films emphasize the importance of careful technic. As a form of pneumoconiosis, asbestosis strikingly indicates the neces sity for clinical study of a case before diagnosis can be made. The film of a patient severely ill with asbestosis may have markings which would appear in significant alongside a typical silicotic film of a man who is actively at work. In the interpretation of asbestotic films the physician must be aware of exaggerated markings attributable to advancing age. This is illustrated in *gure HI. One group comprising 229 men had never been employed in a dusty trade; the other included 80 men en gaged in mining and refining of kaolin by wet methods. The percentage of men who have second degree exaggera tion of linear lung markings in creases with advancing age. It is significant that in this entire group of 309 men there were no cases of ground glass lung field markings, even though this change is observed in the asbestos workers. It appears that the reason why the incidence of -the ground glass type of pulmonic marking is correlated with age is that older people have been exposed to dust for the longest time. Occurrence of asbestotic lung changes --In Figure IV the heights of vertical bars represent the percentages of asbes tos workers in different exposure groups who had ground glass lung field mark ings of either first or second degree. Seventy-six controls have been excluded from this tabulation and a number of workers whose dust exposure was not known have also been omitted. Considering the four dust exposure groups, one at a time, there is a con sistent and regular increase in the per centage of persons with these ground glass markings with increasing length of employment. Age, of course, also increases with length of employment, but these fibrotic changes cannot be ascribed to advancing age because the previous figure (III) showed that fibro tic changes of this degree are not to be expected in workmen of comparable age who are not exposed to siliceous dusts. Note the absence of cases with ground glass markings in the group exposed to less than 5 m.p.p.c.f. Obviously, there are great differences between individuals in the time that elapses from their first exposure to asbestos dust and the time fibrotic evi dence is observed in the X-ray film. In some persons this was much less than S years and in others it appears to be more than 10. Some of the difference 212 American Journal of Public Health Mar., ig3g Figure IV--Percentage of Asbestos Textile Workers, Classified by Average Dust Concentration (Measured in Million Particles per cu. ft.) and Duration of ' Exposure, Found to Have Ground-Glass Lung-Field Markings. is probably due to total amount of asbestos dust inhaled. Difference in amount of physical exertion may play an important role--a person in a seden tary job having a smaller need for oxygen inhales less air and consequently fewer particles of asbestos. It was noted that the relation between dust exposure and the incidence of ground glass lung field markings was not a simple one. Even when length of employment was disregarded, it was found that incidence of these markings was proportionately lower at 10 to 19.9 m.p.p.c.f. than it was at the next higher or next lower concentrations. Although it is probable that these differences rep resented sampling errors due to small numbers of exposed persons, it may be that asbestos fiber excites a different and possibly more severe reaction than asbestos particles. On account of large labor turnover, as well as the short time that the plants had been in operation, no exact estimate of incidence of asbestosis can Table IV Occurrence of Asbestosis in Relation to Dust Concentration and Length of Employment Percentage With Asbestosis Years in Asbestos Industry Dust Exposure, Million Particles per Cubic Foot f Affected 0 to 4.9...........................................< Exposed [ Percentage f Affected 5 to 9.9.......................................... 4 Exposed [ Percentage f Affected Over 10.......................................... < Exposed [ Percentage 0 to 4.9 2 84 2% 0 70 0% 8 134 6% 5 to 9.9 1 19 5% 6 37 16% 22 43 51% Over 10 0 5 0% 13 19 68% 21 36 58% Mar., 1939 { Average Dust )uration of ings. ower at 10 to 19.9 at the next higher trations. Although Lese differences reprrors due to small persons, it may be excites a different evere reaction than rge labor turnover, ort time that the operation, no exact e of asbestosis can %gth of Employment estos Industry to 9,9 1 ;9 5% 6 57 16% 22 43 $1% Vol 29 Asbestosis 213 be made. Table IV shows, however, that the percentage of persons with asbestosis increases greatly with increasjn<r length of employment. Lanza, McConnell, and Fehnel12 reported a similar trend. The incidence also in creases with increasing dust concentra tion. For the reason that there are but few cases with more than IS years' exposure, the percentages in Table IV are necessarily minimal estimates of prevalence of asbestosis even though several of the former employees are included. SAFE LIMITS OF EXPOSURE TO ASBESTOS DUST For practical purposes it is useful to have a definition of safe working conditions. Ideally, a threshold con centration of dust should be the highest dust concentration that would not produce pneumoconiosis in originally healthy workmen during their entire working life. Below 2.5 m.p.p.c.f. the interpretation of Table IV offered no difficulties, since none of 39 persons exposed to that concentration had as bestosis, although only 6 had been em ployed more than 5 years. Three doubtful cases of asbestosis fell in range 2.5 to 4.9 m.p.p.c.f. Because clean-cut cases of asbestosis Table V Percentages of Workers Exposed to Certain Concentrations of Asbestos Dust in Asbestos Textile Factories Where Dust Control Measures Are Used to a Limited Extent and in Factories Where Effective Dust Control Is Practised Limited Use Ditst Concentration of Dust- Million Particles Control per Cubic Foot Measures * Over 10 5 to 9.9 2.5 to 4.9 Under 2.5 48 28 15 9 Data from Table IV. t Data from reference 13. Extensive Use of DustControl Measures 1 17 32 44 ' were found in dust concentrations ex ceeding 5 m.p.p.c.f., and because they were not found at lower concentrations, 5 m.p.p.c.f. may be regarded tentatively as the threshold value for asbestos-dust exposure. A supplemental engineering study13 was made in an asbestos textile factory in which dust control equipment had recently been installed. This showed that means are already available for reducing the dust exposure of a majority of asbestos textile workers to less than S m.p.p.c.f. The basis of this control was exhaust ventilation near source of dust. CONCLUSIONS As in other forms of pneumoconiosis, occupational history, and clinical and X-ray (or pathologic) findings must be in harmony before a sound diagnosis can be made. The occupational history should be a reflection of manufacturing processes since the job designation re fers to a stage in manufacture. The occupations which were found particu larly liable to induce severe forms of asbestosis were willow, pick, card, spin, twist, and cloth weave. Confirmation of the hazardous nature of some of these occupations is the frequency with which the occupational designation of carder, weaver, or spinner is encountered in autopsy reports of cases.14^18 The fol lowing are the outstanding findings determined in this study: 1. In a study of 541 employees of North Carolina textile mills, pulmonary asbestosis was the principal physical defect found. 2. The most serious forms of the disease were observed in carders, spinners, weavers, twisters, willowers, and pickers. 3. Exposures ranged from 0.10 to 76 m.p.p.c.f. 4. Dust contaminants of air in asbestos textile plants are both particulate and fibrous. 5. It is imperative that findings of occupa tional history, clinical examination, and X-ray film all be considered in making diagnosis of a case. 6. Definite clinical and roentgenographic 214 American Journal of Public Health Ma>; 1039 evidence of asbestosis is observed in exposed persons after 5 to 10 years of work in ex posures exceeding 5 m.p.p.c.f. 7. It appears that if asbestos dust concen trations in the air breathed are kept below 5 m.p.p.c.f. new cases of asbestosis will not appear. . 8. Methods for controlling the dust below this tentative threshold are already available for most of the processes in the industry. REFERENCES 1. Gloyne, S, R., and Merewether, E. R. A. Asbestos. Occupation and Health (Suppl.), Inter national Labour Office, Geneva, 1938. 2. Cooke, W. E. Pulmonary Asbestosis. Brit. M. 2:1024-1025, 1927. 3. McDonald, Stuart. Histology of Pulmonary As bestosis. Brit. M. ]., 2:1025-1026, 1927. 4. Hoffman, F. L. Mortality from Respiratory Dis eases in Dusty Trades (Inorganic Dusts). Bull. U. S, Bur. Lab. Stat. No. 231, 1918, pp. 176-180. 5. Fancoast, H. K., Miller, T. G., and Landis, H. R. M. A Roentgenologic Study of the Effects of Dust Inhalation Upon the Lungs. Tr. A. Am. Physicians, 32:97-108, 1917. 6. Mills, R. G. Pulmonary Asbestosis: Report of a Case. Minnesota Med., 13:495-499, 1930. 7. Lynch, K. M., and Smith, W. A. Asbestosis Bodies in Sputum and Lung. J.A.M.A., 95:659-66), 1930. 8. A Study of Asbestosis in the Asbestos Textile Industry. Pub. Health Bull. No. 241, Aug. i0, 9. Gloyne, S. R. The Asbestosis Body. 7 ^ 1:1351-1356 (June 25), 1932 ; Sundius, tsj ,,C5( Bygden, A. Der Staubinhalt einer Asbestosislunee ^ die Beschaffenheit der sogenannten Asbest^ korperchen. Archiv. j. Gewerbepatk, u. Gewerbe^1' 8:26-70, 1937; Gloyne, S. R. The Morbid Anato^' and Histology of Asbestosis. Tubercle, 14 -445 4-^ 493-497; 550-558, 1933. 5I; 10. Kettle, E. H. The Interstitial Reactioi- Caused by Various Dusts and Their Influence ^ Tuberculous Infections. J. Path. & Bact. 35-30- 405, 1932. ' ' ** 11. Stewart, M. J., Tattersall, N., and Haddow A, C. On the Occurrence of Clumps of Asbestos*' Bodies in the Sputum of Asbestos Workers, j pat!s & Bad., 35:737-741, 1932. * '* 12. Lanza, A. J., McConnell, W. J., and Fehnd J. W. Effects of the Inhalation of Asbestos Dust oil the Lungs of Asbestos Workers. Pub. Health 50:1-12, 1935. Reprint No. 1665. ' 13. Page, R. T., and Bloomfield, J. J. A Study of Dust Control Methods in an Asbestos Fabricating Plant. Pub. Health Rep., 52 (Nov. 26), 1037* Reprint No. 1883. ' 14. Lynch, K. M., and Smith, W. A. Pulmonary Asbestosis II. Am. Rev. Tttberc., 23:643-660, 1931 15. Egbert, D. S. Pulmonary Asbestosis. Am.' Re^ Tuberc., 31:25-34, 1935. ' 16. Stock, G. A. Pulmonary Asbestosis. M. Bull Vet. Admin., 10:126-129, 1933. ` 17. White, T, P. Pulmonary Asbestosis. Tr. Mz&, Soc. North Carolina, 1935, pp. 259-262. 18. Lynch, K. M., and Smith, W. A. Carcinoma of Lung in Asbesto-silicosis. Am. J. Cancer, 24 56-64, 1935. '