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FILE NAME Brakes BRK DATE 1978 DOC BRK069 DOCUMENT DESCRIPTION Journal Article - Airborne Asbestos in the Vicinity of a Freeway : PPT TN ka A a AUER MS EP PE get TONTS famSe ad TE Me SARTO oa <a TERRES Lae SON PSP gia SaTEEL tabet ae ATEN. cAet Discussions range 0.5 to 2.0 depending upon atmospheric Schwartz and Newman 1978 For =1 the pressions become respectively stability rate ex- and df OCI dr df Coci Coci dt Adherence to the suggested mechanisms would therefore be indicated by linearity in graphs of , f vs. 2 zero order f2 vs. tminus order * Inspection of Fig 2 shows that these mechanisms may readily be excluded . In conclusion we continue to feel that the use of the graphical method of analysis that we have developed presents a highly valuable tool for elucidating the order of reactions in stack plumes However we recognize that obtaining averages from a set of data a procedure to be employed with caution and we thank Dr. Overton for calling attention to this point Brookhaven National Laboratory Upton New York 11973 U.S.A. J. FORREST L. NEWMAN S. E. SCHWARTZ . REFERENCES Newman L. Forrest J. and Manowitz B. 1975 The application of an isotopic ratio technique to a study of the atmospheric oxidation of sulfur dioxide in the plume from an fired power plant Atmospheric Environment 9 959-968 Schwartz S. E. and Newman L. 1978 Processes limiting the oxidation of sulfur dioxide in stack plumes Environ Sci Technol 12 67 73 Lusis M. and Wiebe H. A. 1976 The rate of oxidation of sulfur dioxide in the plume of a nickel smelter stack Atmospheric Environment 10 793-798 oN NINE Rimes: AIRBORNE ASBESTOS IN THE VICINITY OF A drum debris However in New York City brake repair and brake maintenance facilities practices are such that both FREEWAY fibrous and fibrous particulates are made airbome where they have been shown to persist in local work environments Rohl et al 1975 It is important to note ^fin these occupational circumstances that the levels of asbestos 18/1/1 The 18/1/1 paper by Alste et al which has recently appeared in this detected were considered conservative in that binder journal raises an important question concerning the contri- culates were not included in the air parti- analysis bution disintegrated brake lining dust might make to ambient 3 Limited studies of automotive maintenance asbestos fiber levels These authors have made several have demonstrated workers important observations : chrysotile asbestos fiber survives the and measurable radiographically discernible asbestosis and braking process is present in brake drum debris ; asbestos pulmonary function loss in some 25 of those studied Lorimer et al 1975 More important recent fiber in such debris appears to be reduced in length only with reports have noted that mesothelioma occurs in minimum alteration in crystallinity measurable concen- workers in Canada and Great Britain garage trations of asbestos fibers have been found in areas in which braking operations are common these concentrations Newhouse and Thomson 1965 McDonald et al 1970 Greenberg and ex- Davies 1974 ceed those measured in areas where there is comparatively little braking action 4 Recently a study in the United States demonstrated These findings are so significant that wish that asbestos fiber present in brake lining dust appears to we to amplify and to extend them with some recent observations made in range in crystallinity from unaltered to completely recrystallized fiber Seshan 1977 The relative proportions of our Laboratory and in others 1 Identifiable chrysotile asbestos fiber does indeed survive each of these phases is currently under study Alste et al have demonstrated that braking operations The content of chrysotile in brake drum asbestos fiber is liberated during braking operations In occupational circum- dust in samples examined from New York City has been observed to stances where high concentrations of brake drum dust are range from 2 to 15 as determined by ray diffractometry Rohl et al 1976 Confirmation of the encountered asbestos disease may occur Several years ago in presence of free fiber was obtained by transmission electron an unpublished report we found that higher than ambient concentrations of asbestos fiber were measured at a microscopy selected area electron diffraction and electron the entrance of large crossing tunnel in New York microprobe analysis Similar findings were made on 20 European and Australian brake dust City These concentrations were recorded at low nanogram samples Rohl et al 1977 Therefore what has been found in levels In a recent paper by Bruckman et al 1977 mes- Australia appears to be the case in other areas of the world Observations othelioma was reported in a Connecticut toll booth collector and these investigators found higher concentrations of demonstrating chrysotile present in disintegrated brake lin- bestos in the as- ings have also been made in Great Britain F. Pooley vicinity of highway toll booths than in the ambient air of Connecticut cities personal communication France P. Sebastien personal cornmunication and South Africa Asbestos exposure in brake lining maintenance and repair M. Skikine personal communication We include the workmen may be a significant problem In addition to caveat that clumps of chrysotile fiber exist in the binder particulates and are not degraded brake drum materials they also install new linings and recondition old linings These processes invariably led considered free fiber per se These binder particulates hold most of the under conditions which have existed to asbestos chrysotile liberated from the disintegrated brak~ well exposure | shoe 2 Free asbestos fibers as distinguished from binder particulates constitute a small proportion of the total brake Alste J. Watson D. and Bagg J. 1976 Atmospheric Environment 10 593-589 : Recent reports thus indicate that fiber is liberated during braking operations These reports differ primarily in the relative magnitude of fiber release The importance of the study fibers their concentrations and sizes is now open for We believe this a fruitful area of exploration by air pollution scientists in our country and among other motorized societies DoE ieremesaree:. ee The Moun 10 East 10 New York Bruckman and mese Control | Greenberg register McDonald C. 1970 tumors i Newhouse AI MICF IN The autho explain th east of Bc literature tation gen fall in and tance in th tropical m on convec latitu Howeve interpretat findings re clouds whi producing results mu because of cloud phe to exhibit ; size of the means anc authors s probability chance Ift does sugge microphys tially act t urban are the METE Illinois St. Atmospher Box 232 [ The au _ Changnon The ext research I delineatet changes ( Selvar and Mu 1097-110 _ * Ee Discussions 2031 The Mount Sinai Medical CenterCenter EO 10 East 102 Street E New York NY 10029 U.S.A. ARTHUR N. ROHL ARTHUR M. LANGER IRVING J. SELIKOFF pleura and peritoneum following exposure to asbestos in the London area Br J. ind Med 22 261 269 Lorimer W. V. Rohl A. N. Miller A. Nicholson W. J. and Selikoff L J. 1976 Asbestos exposure of brake repair a workers in the United States Mount Sinai J. Med 43 ee . 207-218 REFERENCES Rohl A. N. Langer A. M. Wolff M. S. and Weisman I. 1976 oe Asbestos exposure during lining maintenance and Bruckman L Rubine R. A. and Christine B. 1977 Asbestos Envir Res 12 110-128 and mesothelioma incidence in Connecticut J. Air Pollut repair Rohl A. N. Langer A. M. Klimentidis R. Wolff M. and e Control Ass 27 121 126 Selikoff I. J. 1977 Asbestos content of dust encountered in Greenberg M. and Davies T. A. 1974 Mesothelioma brake maintenance and repair Proc R. Soc Med 70 register 1967-68 Br med J. 31 91 104 McDonald A. D. Harper A. El Attar O. A. and McDonald J. mesothelial 33-37 Seshan K. 1978 On the utility of dark field electron of defor- C. 1970 Epidemiology of primary malignant in Canada Cancer 26 914-919 microscopy in the determination of the degree tumors Newhouse M. and Thompson M. 1965 Mesothelioma the mation in chrysotile asbestos Envir Res 16 NO" ST 6 nell AIRBORNE ELECTRICAL AND effects of the St. Louis studies Changnon 1977 are the increased cloudiness up 10 the increased summer rainfall MICROPHYSICAL MEASUREMENTS up % and increased severe storm activity up 10 to 100 IN CLOUDS AND MARITIME AND These increases were noticed east of St. Louis over a 4000 km Oe area The results also suggested that urban generated large URBAN ENVIRONMENTS condensation nuclei help initiate coalescence process and The authors are to be complimented on their attempts to explain the previously noted precipitation anomaly in and east of Bombay Their earlier findings add to a growing literature pointing to industrial effects on precipitation generally resulting in additional cloudiness and rainfall in and beyond large urban areas Of particular impor- tance in their findings is the fact that if true a large city in tropical monsoonal climate exhibits the same degree of effect on convective precipitation as has been noted in studies of latitude cities of North America and Europe However the reader should be cautioned about his interpretation of the findings in this particular paper First findings relate only to sampling of fair weather cumuliform clouds which may or may not reflect conditions found in rain- producing cumulus clouds in the area More importantly the results must be taken with a great deal of caution primarily because of the extremely small sample size particularly for cloud phenomena whose incloud characteristics are known to exhibit great natural variability between clouds The large size of the standard deviations presented relative to the means and averages reflect on this sampling concern The authors should concern themselves with determining the probability that the differences are due to anything but chance If the evidence presented is representative sample it does suggest that all suspect influences including electrical microphysical and dynamic influences are present and potentially act together to enhance clouds and precipitation in an urban area This agrees with the findings being derived from the METROMEX studies of St. Louis a latitude city thus make more clouds produce rain . The authors would like to clarify that the results presented in their paper did not relate to sampling of fair weather cumuliform clouds as mentioned in the comments of Pro- fessor Changnon All measurements were made during the - summer monsoon season September During the period of observations the region was under the influence of active monsoon conditions due to favourable synoptic con- ditions The cloud measurements reported are repre- sentative of the cloud conditions prevailing during the summer monsoon However as pointed out by Professor Changnon the results must be taken with a great deal of caution particularly because of the extremely small sample size In this context it may be of interest to note the results of the two studies which were reported earlier Mary Selvam et al The in . 1976a ; 1976b rainfall recorded the downwind vicinity of a thermal power plant showed increases up 25 after the construction of stacks Mary Selvam et al 1976a Also air- borne electrical microphysical and dynamical observations showed differences in the downwind and upwind regions of thermal power plant Mary Selvam et al 1976b It is gratifying to note that our results have been further corroborated by the METROMEX results which showed that the clouds downwind of fossil power plant are altered by the pollution Changnon 1977 Indian Institute of Tropical Meteorology Poona 411 005 India A. MARY SELVAM A. S. RAMACHANDRA MURTY S. K. PAUL Illinois State Water Survey STANLEY A. CHANGNON R. VIJAYAKUMAR Bh V. RAMANA MURTY Atmospheric Sciences Section Box 232 Urbana IL 61801 U.S.A. REFERENCES AUTHORS REPLY The authors would like to thank Professor Stanley A. Changnon for his valuable comments on their paper The extensive studies undertaken at St. Louis under the research Program METROMEX have greatly helped to delineate the existence and causes of induced climatic changes Semonin and Changnon 1974 The key climatic Selvam A. M. Murty A. R. Paul S. K. Vijayakumar R. and Murty V. R. 1978 Atmospheric Environment 12 1097-1101 Changnon Jr. S. A. 1977 Impacts of modified pre- , cipitation on man's activities J. Weather Modific 8 18 Mary Selvam A. Manohar G. K. and Ramana Murty Bh V. 1976a Rainfall variations around a thermal power sta- tion Atmospheric Environment 10 963-968 Mary Selvam A. Ramachandra Murty A. S. Vijayakumar R. and Ramana Murty Bh V. 19766 Airborne electrical and microphysical observations in the environment of a thermal power station Atmospheric Environment 10 957 961 Semonin R. G. and Changnon S. A. > Jr. 1974 MET- ROMEX Summary of 1971-72 results Bull Am m, et Soc 55 95-100