Document RjN7G1Vv30qeGXGdmq4jEL9BE

--- --1WRC construction products division mu TO: R. M. Vining 001215 DATE: 71<531<S7 * PLAINTIFFS (i EXHIBIT WRG-671 June 28, 1972 FROM: H. A. Brown SUBJ: Biological Tests on Tremolite cc: H. C. Duecker PERSONAL & CONFIDENTIAL Attached is a memo which .contains abstracts on two series of biological tests with asbestos fibers. From investigations over the past few months, certain indications are coming to awareness that there may be significant differences between the various types of fibers classified by Webster's Dictionary as asbestos fibers. 1.) The crystalline structure of the fiber may react differently in the lungs. Tremolite, for example, is not a spiral-type fiber such as chrysotile and crocidolite. 2.) There is some evidence that tremolite does not carry carcinogenic materials in the same manner as the other two fibers mentioned above. 3.) Pathological studies made by the researchers in the attached two abstracts highlight the differences in the fibers' effect on animals, but tremolite as bestos was not checked. Duecker and I have discussed this and we are of the opinion that we should investigate the possibility of having tremolite as found at libby, and possibly South Carolina, evaluated in relationship to the other "bad actors". The approach would be to deal with one of the universities that has been doing work of this type and sponsor the tests on tremolite. I realize that it is difficult to assess whether to follow this path or leave it alone, but I believe it warrants some in-depth discussion. HAB/cgr Attachments H. A. Brown 25113091 TO: H.A. Browrf - FROM:'^A fcschenbach CAMBRIDGE /P DATE: June 16, 1972 SUBJECT: Respirators - OSHA 'i63168 'C.C-. 7.L. Lyall REFERENCE: Your Memo, 15 June 1972 I believe that the respirator you are interested in is the "RITE Whitecap" manufactured by Personal Environmental Systems, Inc., Box 800, Glendale, California 91209. It has been on the market for a little over a year, but until recently, it was not approved by the Bureau of Mines. A short time ago, they did approve it and Peter Kostic and Bob Oliverio discussed it and agreed that a field trial was worth our time and effort. Peter has been in Libby for the past week and may return with further information. We will keep you aware of progress in this project. This respirator will enable workers to be exposed to fiber levels exceeding 10 times but less than 100 times the ceiling limit and time weighted average. I doubt if we have concentrations approaching these values. I am awaiting the full abstracts of two papers presented at the American Industrial Hygiene Association Conference. Attached are brief abstracts. We plan to avail ourselves of more current information from this group and the A.M.A. as it develops. I have been circulating pertinent articles to Duecker and occasionally T. Lyall. If you are interested in this technical data, I will be happy to have copies sent to you also. H.A. Eschenbach HAE:mh Enclosures 25113092 i 7163169 ABSTRACTS ABSTRACTS mhc .<!<-* ten Jed to have filler bronchial clcarxiui; U'l^ctn mucus production rate and bToncHms<t,.r t\ft ih.mgci in autonomic nervous control of aird% Jucc changes in Or measured functions of p.irhhie tin *f mucus ir?n ;**rt. Two drugs which moJif> i). .uropinc and mrih,icholtne. were studied for thcif icarance of inhaled particles in the donkey. r. induced by atropine increased alveolar deposition >.us accretion by the submucosal glands, irawhc.il ration of bronchial clearance were not significantly und. increased bronchial deposition by inducing mutated mucus secretion and increased the rate of iliary transport through the trachea was fast initially, ncr stages, due to the accumulation of excess mucus. UBUT10N OF CHROMIUM FOLLOWING S istitutc of Environmental Medicine. New York New York. New York i) have implicated calcium chromate as one of the 1 problem. In current inhalation exposure studies, it c the early clearance and tissue distribution of kUtum chromate aerosols. Following six hours of J at timed intervals up to 48 hours. Chromium 'ird` b\ a-.t.o..m....i*c absorjpmtiioimni mfomllHoiwimng niutrnic aciud In "n viujni.t.e, shoued > range of recover, from ge percent The limn of dcteei.on for the L -L g ml wuh a .inking range from 0 t.. 10 r-fr'ml. yi . is concentrations of chromium in the lung remain*' i.' 24 hours I nna?) concentrations increase for up > subsequent time period*. Concentrations in the gut r J surest this route os a map unite of elimination ihe organs and the significance of these clearance h> No PH43*NCI*M>*%2 from the National mier program supported by the National Institute of (lam No I StkJ2b0. I7G 161. THE EFFECTS OF MASS LOADING OF OUST ON BRONCHIAL CLEARANCE C. PHILLIPS, M. LfPPMANN. PhO.. and R. E. ALBERT. M 0.. Institute Of Environmental Medicine. N. York University Medical Center. New York. New York Studies are being conducted to determine the effects of the mass loading of inert dusts on particle deposition and clearance. The effect of large amounts of inert dust on alveolar clearance, following intratracheal injection rather than by inhalation, lus been studied hy others. These studies showed (hat increasing the lung burden of particles increased the amount of alveolar clearance up to a point, beyond which clearance was reduced as the lungs became congested. /n-v/vo inhalation tests are being conducted using high concentrations of preclassified coal dust. The test subjects are miniature donkeys whose bronchial clearance patterns were previously established. The coal dust aerosol has a CMD - 2.90m and a - 1.30. as determined by optical sizing techniques. The retentions of**mTc tagged ferric oxide particles m the deep lungs, main bronchi and upper thorax regions are measured simultaneously in determine the clearance waves in additional control tests, and in tests immediate* following coal dust exposures. The coal dust aerosol is genci.ued with a Wright Dust Feed, which requires the use of dry onrprated air. To eliminate the effects of dry air inhalation on the clearance pattern, a special humidifier was developed. The dust laden air stream leaves the humidifier at a dry bulb tci*.;vraiure of 38*C and a 95*? relative humidity, and (he donkey breathes from this 30 I pm air stream via nasal catheters. The breathing rate is monitored during the periods of dust inhalation. The effects of high concentrations of coal dust on tagged particle clearance will he ^^ulescribed and discussed. f 162yBIOLOGIC DIFFERENCES IN RESPONSE TO LONG AND SHORT ASBESTOS FIBERS W. E. SMITH. M.D., D. D. HUBERT, and M. S. BADOLLET. Florhanv Madison Campus. Farleigh Dickinson University. Madison. New Jersey. Six preparations of chrysotile were tested by intrapleural injection of hamsters with 25 mg sample suspended in 0.5 ml saline. Each preparation waa tested in a group of 50 hamsters maintained for periods up to 700 days. E,len,ive p|e,,rl idlKsmni developed in hamper, in 1 group, ueaied with ch>toile preparal.on. hav.ng mean f.ber lenglha of >2.5 lo J.9 m.cron. a. mea.ured hy opi.val microscopy and 5.J to 6.9 micron, u measured hy electron microscopy InthestA gsoup.. inttathotacic tumors with characteristic, of plcusal gtewthclwimardevelopcd in 8, 9 and 10 hamsters, respectively. Three other groups of hamsters were treated with preparations of these chrysolite* after further milling that reduced mean fiber tengtt* to 0.37 to 0.86 microns as measured by electron microscopy Only rare fillers exceeded 5 microns in length These 3 preparations induced relatively thin pleural adhesions. No mesotheliomas occurred in hamsters treated with them. _ The findings afford evidence that fihrngenic and carcinogenic actions of chrysolite arr related to physical properties of the fibers. 177 x- 25113093 !! 7163170 abstracts '.TS 191. THE CARCINOGENICITY OF CHLORO'ETHERS. STRUCTURE -- MOVAL OF MEiiCURY VAPOR American Optical Corporat.tr- .ciciil for rnm'vmp mercury v.ipnr fr,.r. rm.iruc vt these materials in rcspirati't OR abon. GaithersDurg. Maryland bureau of Mines have jointly funded mMcuholtc Simulator (DMS). The H.MS .iholic parameters required for compute . mnrmoMng. support, and tesusciut'M rcaitnng and metabolic simulation ;jrc rule, breathing depth, breath velocity release are ail variable over wide rargw vM.rk with respiratory exchange ratios pcrvcntilaiton. In additon, all of these aie the u>e of the device in hostile test at body temperature and completely extent of having a variable funuion.il ce equivalent to that ot humans. ACTIVITY REL' TIONSHIPS B. L. VanDUUr-.CN. Sc.D.. C. KAT2. and 0. M- GOLDSCHMIDT. Ph.0.. Institute of Environmental Medicine. New York University Medical Center. New York. New York In 1968 we reported to this Association on the carcinogenic activity of chloiomethvl methyl ether and biskhlcromcthyll ether in mice and rats (A I H A. conference. St. Louis. Mo . 1968. also. Q. L Van Duuren. */ tit A M A A rth. f.n\ Hruith. H, 472 (1968)). Since that time wc liave examined the carcinogenic activity of a series of structurally related cbloro-ethcrs in which the chlorine atoms are <r* or /l- to the ether oxygen atom, and including open chain, flexible and rigid cyclic structures. Tests have been completed on 15 compi>undf in this category. The animal test systems include skin application m ICR ffa mice and subcutaneous injection in mice and Sprague Daw-Icy rats. In addition to bioassays stereochemical studies were earned out on the compounds tested, also, the chemical reactivity of the compounds tested were CMemmed by: 0) measurement of rate of hydrolysis in an auiomaltCutraring ph-Stat; <ii) the nature of the products formed during hydrolysis, fiii) the reactivity of the comfxiunds with nucleophilic reagents. Some c*f the compounds examined in our work are widely used in chemical industry and may pose serious occupational hazards. It is therefore important to know how information about chemical structure, reactivity and stereochemical aspects can be sued to predict carcinogenic potency in this series of comjvundj. Supported by USPHS Contract PH 7l>2020 from the National Cancer Institute and grant ES 00260 from the National Institute of Environmental Health Sciences. ns in test and validation of respirators ind safer evatu non in hazardous ive 10 he limited, in addition, it will i cases where simulation chambers with including standby physicians. Perhaps i and reproducible test and validation ( 192. FIBROGENICITY AND CARCINOGENICITY OF AMOSITE. mlaior is currently under development puter control. Through a typewriter mio the computer which will then V_^CROClDOUTE. AND CHRYSOTtLE IN ANIMAL EXPERIMENT A. L REEVES. PhD., H. E. PURO. M.D., A. J. VORWALD. M.D.. PhD.. School of Medicine. Wayne State University. Detroit. Michigan: and R. G. Irsired sequence of metabolic activities SMITH, PhD., School of Public Health. University of Michigan. Ann r will also monitor the test procedures eraliun will be indicated tn a motion Arbor, Michigan Rata, rabbits, guinea pigs, and hamsters were exposed to the inhalation of one of three types of asbestos dust at a mean atmospheric concentration of 48 mg'm* (fiber :ation Department ol Pharmacology. California I. diameter 0.2 0 5, fiber length 3-15**) on a lb hr./week schedule for about 2 years, and additional animals were injected with these dusts intratracheal))*, mtrapleurally. or intrapcrttcneaiiy. Histopathologic studies were performed. Amosite was . more fibeogemc than crocid lite or chrysotile. but did not provoke any 4tfifljsij.Y t-ierired by changes in perception. * observed. In neither case was there /T^ wed exposure to manganese fumes 'j ...^ eel: case 2 resulted from inhalation of fiji **/*V,'i - :nrse blood levels were raised in we ired by prolonged disability and slow . r -Jt /*x c Otrysotile caused 5 mcsotheliomaS* in rats after intrapleural or imrapentoneal injections and crocidolm caused 6 mesotheliomas in rats and rabbits after the injections and 2 pulmonary, carcinoma!* in rau after inhalation. Guinea pigs and hamsters developed no neoplasia but responded with more severe fibrosis than rats or rabbits. The fibrogeme property of asbestos fibers might hr inherent ip their silicate lattice; their carcinogenic property is perhaps due to associated trace metals. 189 t\r* ij i 251130^4 it