Document v1aOE5y1QRGnb509YavZwqEBm

> s*<* w. *u> fK'sng i. .r mw'-t 01 me elements <n Me centei ic periodic i*bie such as the transi advantageous to the rapid development of life, is not justified. tion elements. Finally, when the ionic potential is high (> 10) the positive ion ap propriates one or more oxygen ion, freeing Amos Basis Jerzy Navrot Department ofSoil and Water Sciences, the hydrogen and forming an oxyaniem, which is generally soluble: this is charac Hebrew University ofJerusalem. Rehovot. Israel teristic of the ncnmetali in the upper right corner of the periodic table. If life began in the primitive terrestrial oceans, element* whose abundance* in the aqueous phase are high should have a high tifttnmul Htu t. S. Artttcaittt. Worlds In ihe Makiat (Htrrxr A Row. New York. 1901). ^ a. F. H. C Crick tad L. Or**t Icarus 19, HI x 5a" * representation in living material. In Fig. I, the enrichment factor for a number of de ment*--that is. the ratio of the concentra tion of the element in an organism to its concentration in the earth's crust (7)--is plotted against ionic potential. A similar curve is seen for alt major groups of orga nisms. tt we proceed up the evolutionary scale from bacteria to fungi to plants to land animals, and for the ocean (Fig. 2). A genera! pattern is observed for all living organisms: (i) For elements of low ionic potential values (IP < 3) the log of the enrichment factor (EF) is in the range of-I to +1 indicating small enrichment or small depletion relative to the crust, (it) For intermediate IP values (3 < IP < 10) fog EF is ~3 to -4 indicating large de piction in living organisms, (tit) For large IP values (IP > 10) log EF increases as the ionic potential increases and varies from -4 to +4. It should be noted that the ele ments mentioned by Crick and Orgel as showing anomalous distribution patterns-- toe IONIC POTENTIAL Fig. 2. Elements! enrichment factor* in scxwi- ter, related to the ionic potential ofthe elements. may be taken a* a elite to a more exact lo cation for the origin oflifo. It can be specu lated that life began at the interface of the primitive atmosphere and the ocean, in the thin irvicrolayers at the surface of the ocean where large enrichment* of the atmo spheric constituent* (mainly nitrogen and carbon at that stage) may occur. Various other elements may also be concentrated in these microfayet* because of the effects of surface-active material*, surface tension, and the transfer processes between the liq uid and the gaseous phase. In any event, it is evident that a chemical environment similar to the earth's ocean is sufficient to explain the elemental abundance relation ships in living materials. A nonterrestrial 4. T.H.Jvkt*,<bie.. p.514. >, L E. Otfd,ibiti,a.511. tut Knuritopf, lait&lutuon n Otocktmisrry (MeOixw.HilL New Yorit. 19651. 7. D*u m eoectatnuitm ntigtt *m! me*t> **!(** of ctesnenut atnuKUftces wete ccmskd from *< fet. fo*i* loureo: (Fifth's emu) S. R. Taylor. GeocMim. Cotmoekim. A era 22, 12*0(1964). (Sow*, ter) I, f. ftiley end C. Skirrew, 4*. Ckemiest Octanatmpkr {AesUemie Press. New York, 196SX vet. t, (tp. 164-165. ttfacren* n4 fn|i)}, R. Power. Bacterial Chemistry and Phytiotoey <Wifcy. New York. tmi. p. WS: W. $, Speeior, EA. fiondbook of BMofictt Dart {Sweden, Wiildeln*ii*, 1954). pp. M-19: C. Lent Ed, Siocktmisu Handbook. (Sport. London. 1941X no. M50-1052L. twau) H. D. Chspnw*. &L, Diatitostk Criteriafor Ptams andSalts (Unfa. qfCilj. fontia Press. Berkley. J966), p. 793. <Uod *nimlt) M. a. M. Bowen. Tract Elements tn Biotkemlftrf (Aeedemie Press. London. 1946), pp. 174-210. A. Bunin sat i. Nsvrt*. Common. Soil Set. Ptams Ana/. X 177 {1972k Where avsilubie, Bat* foe a mate of conoentiation* were used to ctfcufate s rente ofenrichment factors for a troop of orjanamiL When only the mean concentration wu arraitable, only ooe enrichrt*m factor vahw was fivaL The ionic potential war cakuiated mini crystal radlua valuer shea by t. H. Ahrens (Geockim. Cosmockm. Aero 2. 155 {I9SI)J. For ele ment* appeariof in various oxidation states the mow abundant form war chosen, *. A- L Oparin, in Exobiology, C. Fomtamperunta, Ed. (Nonh-Hoiland, Amnerdam. 1972i p.) 1. 9. For constructive cmicism of this resnurcript e extend one thanks to J. Kronfekf and 1. Cohen. Mo, Ni, and Cr--also follow this general explanation, especially one that has in- tl March 1975 pattern. Specifically, Mo does not show any significant enrichment in living organ isms as" compared to the earth's crust Obviously, taking each element and each group of organisms separately, we may ex Exposure to Asbestos in the Use of Consumer Spackiirtg, pect many exceptions to the rules; still Patching, and Taping Compounds the general pattern is strikingly similar for all the groups of organisms investigated Abstract. Analysis ofrepresentative samples ofspackling, patching. andjointing com- According to Oparin ($), some com pounds, purchased at retail stores in the New York City area, has shown that some con binations of biochemical reactions are tain asbestos minerals as well as other biologically active substances. Measurements sug characteristic of all contemporary orga gest that home repair work involving the use ofsuch materials may result in exposure to nisms. These are combinations of patterns dust at concentrations sufficient to produce disease. acquired by the emerging living matter in its very early stages of development, before Spackling and drywall taping com Fifteen samples of consumer spackling further specialization and differentiation took place. Thus the basic similarity ofthe elemental composition pattern of all pounds consist of extremely fine-grained while powders or premixed pastes. Plaster of Paris is supposedly the major constitu and patching compounds were purchased at hardware stores in the New York City area, four in 1972 or earlier and the re groups of living organisms (Fig. 1) in ent, but other light-colored materials in mainder in January 1974, We analyzed the dicates that the pattern was determined cluding clays, micas, quartz.- talc, and samples for mineral phases by polarized at the initial steps of the development of ground limestone, supplement or replace light microscopy, x-ray powder diffraction, life. the plaster in many formulations. Chryso- and transmission electron microscopy, It should be noted that in the range of tonic potentials higher than 10. where the major biochemical elements sulfur, car bon. and nitrogen are found, organisms haxj a very significant enrichment of 10 to tile is added to some products, apparently because these minute fibers act as rein forcing agents. The presence of amphibole asbestos in some products results from its natural occurrence in talc, carbonates, and with particular attention to quantitative determination of asbestos minerals. The spackling and taping compounds consist mainly of particles smaller than 3 pm in average diameter or length (Fig. 1). Par 'nosi 10.000 relative to the ocean. This other rocks used as raw materials(/). ticles of this size are generally too small to <5 AUGUST 1975 PLAINTIFF'S EXHIBIT Table i. Mineral content of consumer speckling and patching compounds and industrial drywall taping compounds. Frequency of occurrence of mineral phases weight basis. Diagnostic reflections for each of the asbestos mineral* were select ed. These reflections were step-scanned by x-ray diffraction at increments of 0.02* 2 #, where # is the dispersion angle, over a Mineral phue Chrysotile Tremolite Anthophyllite Tile Quartz Feldspar Pyrophyllite Mica Kaolinite Cakhe Dolomite Plaster of Paris Is 15 consumer la 10 spackling and patching industrial drywali taping compound* compounds 3 (5-10*) 1 (4- 6%) 1 (10-12%) 2 9 (5-70%) 1 2 8 5 11 3 7 9(5-12%) 1 (5- 7%) 2 6(10-30%) 9 7 4 4 6 goniometric interval sufficient to define a peak-to-background ratio for tbe diagnos tic reflections. A digital printout of elapsed time in a fixed-count determination was used to prepare precise positions snd pro files of the diagnostic reflections. The area above background, determined with a compensating polar planimetcr, was taken to be proportional to the concentration. Details of the method have been presented elsewhere (2). Samples of spackling and taping compounds were prepared, ana lyzed, and measured under the same condi tions as (he dilution standards. Com parison of the results of known dilution Fig. I Electron photomicrograph of * cons- n spackling product Large numbers of chryrou fibers and fiber bundles are present Granul. particulates are clay, mica, and carbonate mi ens!*. standards with the samples permitted the amounts of asbestos to be estimated with Stituent in two samples and pyrophyflite i be individually studied by polarized light approximately 20 percent reproducibility. two. The crystal structure and physic, microscopy, and identification is further The presence ofcertain minerals may in properties of pryrophyllitc are almot confounded because these compounds terfere with the detection or quantitation identical to those of talc; pyrophyllite ma commonly are mixtures of four or more of chrysotile in spackling and taping com be considered the aluminum analog of tat dilferem materials. The analytical use of pounds. For example, chrysotile and Its biological activity is presently ur the optical microscope with its iimited res kaolinite have similar crystal structures known. Quartz was a major constituent i olution allows large numbers of fibers to and consequently similar x-ray diffraction seven of the samples, and it was present < go undetected. The asbestos minerals, in patterns (3). However,' electron micros two others in lesser concentrations. On t> particular, are usually too fine-grained to copy can be used to corroborate the re basis of the x-ray intensities of several m; identify. In such circumstances, x-ray pow sults of x-ray diffraction and to directly jor quartz reflections, including those . . .der diffraction may be used to identify and estimate the asbestos contest of materials, 4.26, 3 34 and 1.S17 A, the amount < quantify the individual crystalline phases since each mineral type has a characteristic quartz present is estimated to be great< present in the mixtures. morphology and electron diffraction pat than 10 percent in the seven samples. Opi In this investigation the amounts of as tern. cal and transmission electron rrticrosco- bestos present in spackling compounds was The results of the analyses of 15 con have shown essentially all the quartz to 1 determined by comparison with dilution sumer spackling and patching compounds of respirable size (< 5 am). Both qua- standards (2). Binary systems of chrysotile, are given in Table I. Three of the samples and talc can produce pulmonary fibres iremolitc, and anthophyllite asbestos in were found to contain chrysotile asbestos, (silicosis, talcosis) (4). One sample cor plaster of Paris {CaSO '/>H,0) were pre and two others contained trcmolhe and an- sisted largely of quartz with lesser amoun pared at varying dilutions on a wdght-to- thophyilite asbestos. Talc was a major con- of feldspar and anthophyllite. This may ii dicate that the source material for ih product was art anthophyllite schist T1 Table 2. Asbestos fiber concentrations during use of Uping compounds containing asbestos miner als. Multiplication of the number of fibers per milliliter by 10* gives the number of 6bers per cubic meter of air, an amount which may be inhaled during 1 hour. An unstudied proportion of these fibers is retained and others are exhaled. Current (interim) regulations of the OSHA prohibit concentra tions of 5 fibers per milliliter or more, longer than 5 tun, as a time-weighted average for workers. Concentrations above 2 fiber* per milliliter will be ifiegal-aftcr 1976. Current regulations set a ceil ing concentration of 10 fibers, longer than 5 jun, per milliliter of air. ______________ ________ combination of talc with some tremoli and quartz in another sample represents common mineral association typical commercial talc ore bodies. Both optical and electron microscoanalyses showed that the asbestos fibc Operations Number ofsamples Peak fiber concentration (fiber* per milliliter) Mean Range present in the samples ranged in lent from 0.25 to 8.0 pm. Most were shor than 5 pm in length, which is respirat size, yet they were not generally detect Pole-sanding (1 to 1.5 m) Background (2J m). same room Backgtound (7.5 m), adjacent room Hand-sanding (1 to 1.5 m) Background (25 m), same room Background (4.5 m), adjacent room Dry mixing (1 to 1.5 m) Background (3 to 6 m), same room Background (5 to 10 m), adjacent room 10 10.0 3 8.6 2 4.8 11 5.3 2 23 2 4.3 2 47.2 3 5.8 2 26 1.2 to 19.3 3.5 to 19.8 0.7 to 8.8 1.3 to 16.9 21 to 25 1.5 to 7.1 35.4 to 59.0 0.5 to 13.1 21 to 3.1 by optical microscopy. The possibility of asbestos exposure d ing home construction and repair is dicatcd by the fact that drywali constr tioa workers are exposed to significconcentrations of asbestos air c lamination. Mineralogical analyses of industrial drywali taping compounds s: Sweeping floor (3 to 15 m) 15 Minutes after sweeping 35 Minutes after sweeping 1 41.4 l 26.4 that nine contain chrysotile, in concen tions ranging from 5 to 12 percent weight) (Table I). SCIENCE. VOL. 1 2p Medical Research Society The chemistry and physical characteristics of these ing fibre glass, produce these cancers when the fibres minerals vary appreciably and it is with a knowledge are as fine as those of asbestos. of such physical and chemical characteristics that single particles of the minerals can be identified with considerable confidence. D. EXPERIMENTAL AND FUTURE STUDIES The considerable industrial importance of asbestos minerals depends upon the very fine fibrous nature J. C. Wagner of the materials and their chemical inertness. Fibres formed from the varying minerals which are released and inhaled are mainly submicroscopic in size so that it is only with sophisticated equipment such as the transmission electron microscope that they can be seen. With modern developments in electron optical and X-ray analytical equipment it is now possible to chemically analyse these submicroscopic fibres and identify them positively. This enables assays of diseased tissue to be made for their mineral content down to the single particle level. Particles from very well defined areas of tissue can also be isolated and determined with relative ease. Previous techniques of tissue analysis relied mainly on bulk extraction together with bulk analysis for identification pur poses, with the modern analysis techniques now avail able the various chemical phases are readily separated. M.R.C. Pneumoconiosis Unit, Llandough Hospital, Penarth, Glam. Using experimental methods, we have tried to answer some of the questions posed by the epidemiologists, physicists and chemists. It has been possible to produce asbestosis, mesotheliomas, and carcinomas of the lung by using caesarian derived barrier protected rats. We have also been able to confirm that it is the fineness of the fibres that is important and that this not only applies to asbestos but to other fibrous dusts. By using standard reference samples prepared by the physicists we have been able to study and compare the effects of the different types of asbestos on this model. Our future concern is towards the early diagnosis and treatment of the mesotheliomas which in certain heavily exposed populations have reached epidemic proportions. It is hoped that by developing a system of immunological surveillance we will be able to recog nize those among the populations at high risk who are C. THE PHYSICIST'S APPROACH TO ASBESTOS CANCERS most likely to develop these tumours. It is considered that if effective immunotherapy can be applied at this stage, it may at least be possible to delay the develop V. Timbrell ment of these appalling tumours, for which no known treatment is effective. M. R.C. Pneumoconiosis Unit, Llandough Hospital, Penarth, Glam. For inhaled particles to penetrate deeply into the COMMUNICATIONS lungs, they must be of small aerodynamic size. In the 1. ALLERGIC ASPECTS OF ASTHMA IN THE case of a fibre, this is roughly proportional to the HIGHLANDS OF PAPUA NEW GUINEA diameter and virtually independent of length. The fact that amphibole asbestos from different geo H. R. Anderson graphical areas vary in their diameter distributions indicates that they differ in the extent to which they penetrate to the pulmonary regions associated with asbestosis, lung carcinoma and pleural mesothe M.R.C. Pneumoconiosis Unit, Llandough Hospital, Penarth, Glam. (Introduced by J. E. Cotes) lioma. Substantial fibre length militates against deep Asthma in the highlands of Papua New Guinea has a penetration, as also does the curly shape of chrysotile lower prevalence and later age at onset than in fibres. The fibres most likely to penetrate to the pleura Western countries. Of forty-eight patients, all showed are short, thin, straight fibres. Crocidolite from the cutaneous sensitivity to D. pteronyssinus: multiple N. W. Cape is particularly rich in such fibres and sensitivity to allergens appeared more common with has been the asbestos most associated with the forma increasing age at onset. Among 335 unselected tion of pleural mesotheliomas. controls, 19% were sensitive to allergens, 14% of These aerodynamic considerations do not apply to them to D. pteronyssinus (Anderson, 1974, Clinical intrapleural injection experiments. The mesothe Allergy, in press). liomas produced in these studies appear to be related The levels of IgE antibody have been determined primarily to the fineness of the fibre. Chrysotile in these subjects and although asthmatics have higher asbestos, which produces extremely fine fibrils by levels than controls, there is considerable overlap fragmentation in lung fluids, is particularly carcino and both groups have higher levels than their counter genic in this situation. Chemical composition seems parts in an Australian community. IgE levels in to be of secondary importance in the formation of controls were positively correlated with egg counts of these mesotheliomas, and other types of fibre, includ intestinal parasites particularly hookworm: this t support commit! cutanco' in the a* that astl specific The 1 does no tendcncexclude, mental 2. THI TONE t Malco: Cardan Califon- (Introd- The pato has, motor Airwa-. Studies: implies' reficx reduce lions. '. constr. The hist.ur. by me., dogs it In cacchange rangtn 2 mm perfor meastr elect r:. In se\ way reduc had 1 were prodi. stirm. patre : dose- const vagal reque Th Sif re react bloc, platr uCINE \ugust 1974 S 97-104 I05-II7 119-129 131-141 143-151 153-164 165-172 173-178 179-187 fife TClliinical Science and Molecular Medicine 1S9-I92 Ip Ip-lOp