International Joint Commission. Great Lakes Regional Office

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University of WindsorScholarship at UWindsorInternational Joint Commission (IJC) Digital Archive1975-03-03Asbestos in the Great Lakes Basin with Emphasison Lake Superior: A Briefing DocumentInternational Joint Commission. Great Lakes Regional OfficeFollow this and additional works at: http://scholar.uwindsor.ca/ijcarchiveThis Publication is brought to you for free and open access by Scholarship at UWindsor. It has been accepted for inclusion in International JointCommission (IJC) Digital Archive by an authorized administrator of Scholarship at UWindsor. For more information, please contactscholarship@uwindsor.ca.Recommended CitationInternational Joint Commission. Great Lakes Regional Office (1975). Asbestos in the Great Lakes Basin with Emphasis on LakeSuperior: A Briefing Document. International Joint Commission (IJC) Digital Archive. http://scholar.uwindsor.ca/ijcarchive/91  ASBESTOS IN THE GREAT LAKES BASINwith Emphasis on Lake SuperiorA BRIEFING DOCUMENTprepared forTHE INTERNATIONAL JOINT COMMISSIONMARCH 3, 1975    ASBESTOS IN THE GREAT LAKES BASININTRODUCTIONInMarch1974,theGreatLakesResearchAdvisoryBoarddirectedRegionalOffice staffto prepare astate—of—the-artreport on the statusof researchinvestigations on asbestos in the GreatLakes Basin.A pre-liminaryreview draftof the report was presentedto the ResearchAdvisoryandWater Quality boardsin June.A revised draftwaspresented tothetwoboards in Septemberandat the Commission'sOctobermeetingitwasdecided to delay submissionofthereporttotheCommission untiltheU.S. EnvironmentalProtection Agencyhadconsolidateditscommentsintoonereview.TheFebruary1975documentincorporatespertinentcomments from the various reviews.Thereportpresentschaptersontheproperties of asbestos;analyticalmethods;healtheffects;treatmentandremoval;distributionthroughout theGreatLakesBasin,particularlyintheLake Superior;researchneedsandconclusions.Appendices concernthecurrent investigations andmaterialsrelating to the Reserve Mining Case.This document summarizestheinformationintheResearchAdvisoryBoard'sreportandgivestheCommission theobjectiveviewsoftheRegionalOfficestaff inlight ofthemostrecent researchprogressandprograms.PROPERTIES OF ASBESTOS Thegeneric termasbestosdescribesvarious fibrousmineral silicateswhich are hydrated and contain 40 to60%silica combinedwithoxides of metalssuch as ironandmagnesium.Asbestosmineralspresent awide range of fibrediameter(fibre:bydefinition,a mineralform three times as longaswide),tensile strength,flexibility,andsurface properties.Thetwomajorvarietiesofasbestosformsarethesheetsilicates(chrysotile)andthefibrous orblock—like amphiboles(anthophyllite,cummingtonite,grunerite, crocidolite,tremolite, eckermanite).Thesmalldifferencesintheirbasiccrystal unitcell physical dimensionsmake it difficulttodifferentiate among theseminerals.Moreover,inmany instances,chemicalcompositionsmayoverlap.   Ninety per cent of the commercially-valuable form of asbestos isChrysotile, which occurs in curved, open fibre bundles. These easilyfragment into tubular fibrils. By comparison, the amphiboles havestraight fibres which do not readily fracture or change shape.Asbestos fibres vary in their porosity and permeability. The changingelectrical surface charge of asbestos fibres resulting from variationsin pH (a measure of acidity or alkalinity) determines the conditionsfor their dispersion, flocculation, and precipitation. Chrysotileflocculates at a pH of 11.8 (alkaline); cummingtonite requires slightlyacidic conditions at a pH of 5.2 to 6.0.DISTRIBUTIONAsbestos fibres are found throughout the Great Lakes System in theair and water, but only Chrysotile is found in most localities. The fibresresult from natural processes as well as from mining, milling andbeneficiation processes and their wastes; manufacturing operations; andthrough use of commercial products (over 3000) containing asbestos.Fibres which reach the atmosphere are transported by air currentsfrom the point sources. Dust prevention measures and stack filtersreduce but do not eliminate release of the fibres to the air. Theasbestos fibres input to the Great Lakes from dry fallout and dust washedout of the air by precipitation is presently not known; however, currentinvestigations may provide some data.Basin potable water supplies havebeen sampled by various U.S. andCanadian agencies. Chrysotile is found in most locales tested; amphibolefibres of the cummingtonite-grunerite type are found exclusively in thewestern end of Lake Superior and can be traced to the Reserve MiningCompany's taconitetailings discharge at Silver Bay, Minnesota. Typicalconcentrations of Chrysotile asbestiform fibres in distribution systemsaverage 1.6 x 106 fibres per litre with 90 per cent of the areas measuredtesting under 3 x 106 fibres per litre. Duluth, however, averaged 44 x 106fibres of amphibole per litre from March 1973 through January 1974.Filtration systems now in use remove up to 90 per cent of the fibres.Research is continuing in improving the efficiency of filtration systems.  Sediment sampling programs have been conducted at the western endof Lake Superior. Asbestiform amphibole fibres have been found inassociation with taconite tailings to a depth of 7 cms in an area 6 milesinto the lake from Silver Bay.The nature of water movement in the western end of Lake Superior isgenerally counterclockwise and slow. However, amphibole fibres havebeen found in the water supply of Thunder Bay. These may be caused byan annual short—term change in the current patterns.ENUMERATION AND IDENTIFICATION Sophisticated equipment has been utilized for several years to studya wide range of materials and their characteristics in the micrometreand submicrometre range. The transmission electron microscope, and thetechniques of selected area electron diffraction_and electron microprobeanalysis were utilized to detect and identify asbestos and asbestiformfibres in atmospheric samples prior to their application to aqueous samples.Considerable skill, training, and care are required to ensure proper operationof the equipment and proper interpretation of its input.The presence of asbestos and asbestiform fibres in public water suppliesrequires not only detection and identification but also quantificationof these materials. The methodology for sample collection, handling, andpreparation for analysis consists of several sequential steps, each ofwhich may introduce a bias or a loss of precision into the final result.In addition, for each step variations exist which have emerged based.upon analyst and equipment requirements and constraints; comparabilityof these alternatives has not necessarily been demonstrated. A quantitative,bias-free procedure has not been required until recently. The developmentof a standard method has not been intensively pursued since more time andmoney are required than most jurisdictions have available. Possibly onecould not be developed until now since the methodology required rathercomplete characterization.The present instrumentation available appears more than adequate todetect, identify, and quantify asbestos and asbestiform fibres. Presentanalytical methodology for preparing samples for analysis can provideadequate precision. The thrust of present work should be directed towardthe development of a standard procedure to ensure that the sampleanalyzed is accurately representative of the body of water from whichthe sample was withdrawn; i.e. that the number and the nature of thefibres remain unaltered. Concurrently, a viable quality control schemeneeds to be developed and implemented to ensure the validity of analyticalresults.HEALTH ASPECTSFrom industrial experience inhaled asbestos fibres are known to becarcinogenic. The threshold value beneath which carcinogenic effectsdo not occur is unknown nor has a dose response curve been established.The relative carcinogenicity of different forms of asbestos has notbeen determined, nor is it known if the length of fibres inhaled is‘pertinent.The question of whether or not ingested asbestos fibres arecarcinogenic - and if so, at what dosage - is not only unanswered, it isjust now beginning to be intensively addressed. If animal feeding studiesresult in asbestos associated cancers, it is a virtual certainty thatingested asbestos will be adjudged a human carcinogen, despite thepossibility of interspecies incomparability. 0n the other hand, if cancersdo not ensue from the feeding of asbestos, it is a virtual certainty thatthe question of the carcinogenicity of ingested asbestos to man will bedeemed unanswered due to the possibility of interspecies incomparability.This possibility is enhanced by the extended latent period observed in thedevelopment of cancers associated with inhaled asbestos.Given the uncertainty as to the health effects, if any, of ingestedasbestos, the U.S. Federal judiciary has wrestled with the problem ofbalancing equities in a case where one possible equity, human life, hasno corre3ponding right, claim or interest which can be balanced against it.The Federal Court of the District of Minnesota has estimated the unknownprobabilities as requiring the cessation of Reserve Mining's operations.This estimation has not won the assent of the Appellate Courts. At the      present time there is essentially no evidence to either support or refutethe District Court's estimation.RESEARCH STATUSIn its report the Board pointed to eleven specific research needs.These can be divided into areas of health, analytical methods, distributionand material balance.Health research needs listed are currently under investigation bythe U.S. EPA, Duluth, CCIW and MOE. EPA's asbestos feeding studiesmay provide the answers to questions about the short-term effects of asbestos.Their experiments relating to fibres in drinking water should also provideuseful results. CCIW and Ontario Ministry of the Environment arecooperating in efforts to greatly improve removal of asbestiform fibresfrom drinking water. EPA also has a major program to improve and,if possible, standardize sampling and analytical procedures for identificationand counting asbestos fibres.CCIW and EPA are examining aspects of distribution, including speciesconcentration and fibre length in water and sediments. Their researchis concentrated, but not limited to the upper lakes, particularly LakeSuperior. Sources and magnitudes of atmospheric contributions ofasbestos to the waters of the upper lakes are being investigatedcooperatively by the International Reference Group on Upper Lakes Pollution.This group is also examining the likelihood of transboundary pollution.Listed research needs which presently are not being addressed includeinvestigation of the manner in which asbestiform minerals weather and gointo solution; determination of the significance of resuspension ofasbestos from lake-bottom and from land; compilation of an inventory ofproduction, use, disposal and ultimate fate of asbestos products; andevaluation of the potentiating effects of asbestos fibres and metalsassociated with them by pathogens including viruses. These areas ofresearch appear less important than those already being addressed.   They are, however, areas to be examined in the future.Themost pressing needistoimprove thesamplecollection andpreparationprocedures preliminary to identifying andenumeratingasbestosfibres.Without propersamplingandsamplepreparationallthefollowinganalyticalstepsareopen to question.Researchresults tooarethereforealsosubject to question.RegionalOfficestaffbelieve theCommission shouldurge continuedemphasisonanalytical sampling,quality control, andstandardproceduresbyparticipating agencies.Determininganddefiningpotentialhumanhealthhazards,preciselydetailingdistribution(thetwoothermajor research needs),andthevalidityof all ongoing and futureresearcharedependentupon advancingthestateoftheartofsampling,samplepreparationandanalytical proceduresquality control.   DRAFTPat Bonner963—9041 (Detroit)256-7821 (Windsor)IJC RELEASES ASBESTOS REPORTThe International Joint Commission today forwarded to Governmentsits Research Advisory Board's report,"Asbestos in the Great Lakeswith Emphasis on Lake Superior."U.S. Chairman,Christian A. Herter, explained that the Boardbeganpreparation ofthereportin March1974in responsetoitsmembers'and the Commission's expressed interest in gaining an objectiveperspective on the issues relating to the asbestos question,particularlythe transboundary pollution and public health aspectsAfter intensive review by the Research Advisory Board, the Water QualityBoard and their member agencies,the report was submitted to theCommission this week.Professor Maxwell Cohen, Canadian Chairman,said that he believedthe Board did provide an objective state-of—the—art report by bringingtogether published literature and stating the progress of ongoing programs.Four conclusions are presented in the report.1.There are problemswith identifying and counting asbestos fibres.2.Despite the problems,sampling programs will continue because of potential health hazards.3.Thehazards from inhaled asbestos are proven, but scientists do not agree abouthazards resulting from ingested fibres (swallowed).4.There is possibletransboundary pollution from asbestos in Lake Superior.0f the eleven recommended areas of research which the Board proposed,-more-   theCommissionstressedthreeinitssubmissiontoGovernments:improvementofproceduresofsamplecollectionandpreparation—for—analysis,evaluationofpresentandpredictedfuturelevelsofasbestosspecies,concentrationsandsizedistributioninair,surfacewatersandsedimentsintheGreatLakes;anddeterminationofpublichealtheffectsofasbestosfibresin drinking water.Thereporthaschaptersconcerningthepropertiesofasbestos,itsenumerationandidentification,healtheffects,treatmentandremovalfromwater,distributionintheGreatLakesBasinanditspresenceinLakeSuperior.AppendicesrelatetocurrentinvestigationsandinformationconcerningtheReserve MiningCorporation'staconiteminingoperations.Copiesofthereportarelimited.Thedocumentcanbeobtainedfrom’theCommission'sRegionalOffice,100OuelletteAvenue,Windsor,Ontario N9A6T3.Additional copieswill soonbemade availablethrough theNationalTechnicalInformation Service, Springfield, Virginia._30_    UC NEWSGreat Lakes Regional Gi’i’ice Pat Bonner ' ‘.‘. 963-9041 (Detroit)INTERNATIONAL JOINT COMMISSIONContaCt' 256-7821(Windsor)100 Ouellette Ave.. Windscr, Om. N9A 6T3 Telephone:TECHNECALNQTESASBESTOS IN THE GREAT LAKES BASININTRODUCTION’ In March 1974, the Great Lakes Research Advisory Board directedRegional Office staff to prepare a state-of-the-art report on the statusof research investigations on asbestos in the Great Lakes Basin.TheFebruary 1975 document incorporates pertinent comments from the reviewsconducted by the Research Advisory and Water Quality boards and theirmember agencies.The report presents chapters on the properties of asbestos; analyticalmethods; health effects; treatment and removal; distribution throughout theGreat Lakes Basin, particularly in Lake Superior; research needs andconclusions.Appendices concern the current investigations and materials re—lating to the Resarve Mining Case.This document summarizes the information in the Research Advisory Board'sreport and provides additional comments in light of the most resent researchprogress and programs.PROPERTIES OF ASBESTOSThe generic term asbestos describes various fibrous mineral silicates" which are hydrated and contain 40 to 60% silica combined with oxides of metals'such as iron and magnesium. (Asbestos minerals present a wide range of fibrediameter (fibrez' by definition, a mineral form three times as long as wide),r'r‘ - tensile strength, flexibility, and surface properties. The two majorvarieties of asbestos forms are the sheet silicates (chrysotile) and the fibrousor block—like amphiboles (anthophyllite, cummingtonite, grunerite, corcidolite,tremolite, eckermanite). The small differences in their basic crystal unitcell physical dimensions make it difficult to differentiate among theseminerals. Moreover, in many instances, chemical compositions may overlap.They are, however, areas to be examined in the future.The most pressing need is to improve the sample collection and prepar—ation procedures preliminary to identifying and enumerating asbestos fibres.Without proper sampling and sample preparation all the following analyticalsteps are open to question. Research results too are therefore alsosubject to question.The International Joint Commission has urged continued emphasison analytical sampling, quality control, and standard procedures bypartic-ipating agencies. Determining and defining potential human health hazards,precisely detailing distribution (the two other major research needs), andthe validity of all ongoing and future research are dependent upon advancingthe state of the art of sampling, sample preparation and analytical proceduresquality control.    

Asbestos in the Great Lakes Basin with Emphasis on Lake Superior: A Briefing Document

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Asbestos in the Great Lakes Basin with Emphasis on Lake Superior: A Briefing Document

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