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Analysis of Vermiculite & Vermiculite Containing Products

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Analysis of Vermiculite & Vermiculite Containing Products The Official Newsletter of the Environmental Information Association EIA Board of Directors Inside EIA PRESIDENT Mike Schrum VOLUME 14, ISSUE 3 M A R C H 2 0 1 5 PRESIDENT-ELECT Kevin Cannan VICE PRESIDENT Chris Gates Analysis of Vermiculite & Vermiculite Containing Products TREASURER Steve Fulford By Ed Cahill, Vice President - Asbestos Division of EMSL Analytical, Inc. SECRETARY There is currently a lot of alone contain VAI. W.R. Grace vermiculite itself but rather the Joy Finch asbestos that may be present attention being paid to purchased the Libby mine in PAST PRESIDENT analysis of Vermiculite and 1963 and greatly increased its as an accessory mineral or Dana Nicodemus products containing Vermicu- production until 1990, when it contaminant. The EPA along DIRECTORS Kyle Burroughs lite. Vermiculite is a naturally was closed. Prior to its closing with the Agency for Toxic Sub- Robert DeMalo occurring mineral composed much of the world’s supply of stances and Disease Registry Jeffrey Feeley Caroline Fungaroli of shiny flakes that resemble vermiculite came from this (ATSDR) initiated a national Dave Hogue mica. Vermiculite when mine. It was the source of over consumer awareness program Chris Walker heated expands into wormlike 70% of all vermiculite sold in in 2003 to educate the public NATIONAL OFFICE STAFF accordion shaped pieces up the U.S. from 1919 to 1990. on the topic of asbestos in J. Brent Kynoch to 30 times Because of its Vermiculite Attic Insulation Managing Director Kim Goodman their origi- properties as an (VAI). Asbestos contamination Membership & Marketing nal size. insulator and can be found in vermiculite Manager Nehmesah Israel Because of because it is ex- from other mines however Administrative Assistant all the air tremely lightweight, Libby was unique in the Kelly Rutt Development & Commun. pockets chemically resistant amount of asbestos Manager created and also fireproof, present. Vermiculite is cur- when this Vermiculite ended rently mined at three other expansion occurs the material up as a constituent in many US locations and abroad I N S I D E is a great thermal insulator. different building materials. It and has relatively low levels THIS ISSUE: One of the most productive also worked very well as a of asbestos contamination. Vermiculite mines was locat- carrier for chemicals in fertiliz- The primary concern with ed in Libby Montana. Gold ers. Vermiculite was used in asbestos is inhalation which Analysis of Vermiculite 1 miners discovered vermiculite its pure form as packing can lead to lung diseases such at the mine in 1881. In the material, attic insulation, as asbestosis, lung cancer and Purple Book Preview 4 1920s the Zonolite Company block fill insulation in founda- mesothelioma. The asbestos formed and began mining it. tions. It was used as a found in loose vermiculite argu- The vermiculite at the mine constituent in insulating and ably poses a greater risk since Editor: was ground down to a specific fireproof boards and molded it is not bound in the matrix as with other building materials. Chris Gates, size (beneficiation) depending shapes for furnaces and fire- ANALYTICAL APPROACHES Dunn Environmental on its final intended use, and places, sprayed on fireproof- then puffed up or expanded ing, acoustic panels, brake As stated earlier, the vermic- in a furnace (exfoliation). The linings, various cement and ulite itself is typically not the final product was packaged concrete mixtures, plasters, target analyte but rather the and sold as Zonolite insula- soil conditioners, seed germi- asbestos that may be present Mission Statement as a contaminant. The vermicu- of the Environmental tion. This product was nation, chemical spill kits, etc. Information Association distributed mostly by rail, all Unfortunately the Libby lite actually obstructs that The Association’s multi disciplinary membership across North America and mine had a natural deposit of analysis. For various reasons will collect, generate and ended up in the attics of asbestos running through it Vermiculite represents a prob- disseminate information concerning environmental millions of homes as Vermicu- which contaminated the lem matrix for asbestos health hazards to vermiculite product. The analysis by microscopy. One occupants of buildings, lite Attic Insulation (VAI). No industrial sites & one knows exactly, but it is current concern over vermicu- reason is that since the size of other facility operations. estimated that up to 35 lite and vermiculite containing the vermiculite plates can be million homes in the U.S. materials (VCMs) is not the orders of magnitude larger P A G E 2 Analysis of Vermiculite—continued than the asbestos we are looking for, it gives smaller This type of matrix modification is described in the EPA asbestos fibers and bundles plenty of places to hide. In some 600/R-93/116 PLM method. Though many think of the samples, larger rice grain sized bundles of asbestos are pre- California Air Resource Board (CARB) Method 435 when sent and can even be seen to the naked (trained) eye upon milling is mentioned, there is nothing truly unique about this method. It is a PLM 400 point count with milling prior to further prep and analysis. The EPA PLM analysis method is much more comprehensive than that of CARB 435 and outside of California the end user may want to stand behind results derived from an EPA method. The downside of the milling approach is that all of the non-asbestos material is now present in the slide prep along with any asbestos that may be there as well. The upside is that this can actually careful examination. aid the analyst in the determination of the true percentage of asbestos in the sample. Another issue with asbestos analysis of loose fill vermiculite is New York State Method 198.8 that the asbestos is generally not distributed uniformly New York State has made Vermiculite and Vermiculite throughout which makes the task of obtaining an accurate Containing Materials (VCMs) a main issue since 2012. New percentage difficult, if not impossible. York State currently mandates that any and all loose fill Cincinnati Method (EPA/600/R-04/004) vermiculite be considered Asbestos Containing Material Early on the EPA suggested this method for determining (ACM). No analysis necessary, no analysis allowed, and no the asbestos content of Vermiculite. It took advantage of the analysis results will be entertained, to consider this material fact that the larger bundles of asbestos would rapidly settle anything other than ACM. A few other states and Canadian out in water (aka “sinks”) leaving the Vermiculite floating on provinces presume loose fill vermiculite to be ACM but do the surface. In a sense, this approach was an elegant way to not disallow analysis to prove otherwise. Beyond loose fill separate the wheat from the chaff. After settling the vermicu- vermiculite, NY also now has special analysis rules for lite is skimmed off the top and discarded. The suspension is building materials (other than sprayed-on fireproofing) aspirated off and saved for optional subsequent TEM analysis containing greater than 10% vermiculite (think textures and leaving the “sinks” to be dried and analyzed by Polarized Light popcorn ceiling). These materials must undergo gravimetric Microscopy (PLM). It starts with a rather large sample (a kilo- reduction prior to PLM analysis via the NYS ELAP 198.6 gram is collected and sent to the lab) and if the large bundles Method. As per the latest NYS ELAP guidance, the following were present, the technique provided a good means of disclaimer must accompany these results; “This method concentrating any asbestos present for detection by light does not remove vermiculite and may underestimate the microscopy. If only fine fibers are present they may go level of asbestos present in a sample containing greater undetected with this method unless the optional TEM analysis than 10% vermiculite.” is performed on the water wash. The TEM analysis provides And finally, for spray on fireproofing containing any results expressed as fibers per gram and this can be of amount of vermiculite (SOF-V), New York has created a new limited value to the end user trying to apply an action level method designed specifically for this material type, New expressed as a percentage. This method is rather time York ELAP method 198.8. This method, even more labor consuming and laborious (and therefore relatively expensive) intensive than the Cincinnati method, is a two stage analy- for routine analysis and so was under-utilized. sis. The first stage involves gravimetric reduction by ashing EPA 600/R-93/116 in a muffle furnace, acid treatment and then painstaking As an alternative to the Cincinnati method many are simply removal of any floating vermiculite prior to a PLM analysis leaning back on the standard EPA 600 PLM analysis. Howev- for Chrysotile Asbestos. If >1% asbestos is detected analy- er the presence of large vermiculite books can hinder a sis is terminated, otherwise a second phase of prep and proper monolayer slide prep for analysis (necessary for proper analysis is initiated. This second phase involves gravimetric quantitation) as well as obscure asbestos fibers. reduction again but this time by heavy liquid separation. EPA 600/R-93/116 with milling (aka CARB 435) The ashed and acid treated residue is dispersed in Lithium As a means to address the large particle size and inherent Meta-Tungstate, a liquid that is mixed with fiber free water heterogeneity of the vermiculite, the sample can be lightly to obtain a liquid with a density between vermiculite and milled to reduce the particle size prior to prep and analysis. amphibole asbestos. When the sample is centrifuged at EIA 2015 Exhibit & Sponsorship Opportunities Available—You DO NOT Want to Miss! Call 888-343-4342 for more info! Sponsorships start at just $150! VOLUME 14, ISSUE 3 P A G E 3 Analysis of Vermiculite—continued approximately 3600 rpm, the vermiculite rises to the top and Financial Relief the amphibole settles to the bottom of the centrifuge tube.
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