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FILE NAME: RT Vanderbilt (RTV) DATE: 2004 Oct 29 DOC#: RTV230 DOCUMENT DESCRIPTION: Langerletter Letter RE Studies of Vanderbilt Asbestosis Mines Stating No Asbestos Minerals Found October 29,2004 M s. Nora Grimbergen, Esquire Hoagland, Longo, Moran, Dunst & Doukas, L L P . 40 Paterson Street New Brunswick, New Je rse y 08903 . D ear Ms. Grimbergen: J have studied the occurrence, properties, and human health effects of minerals and mineral com m odities for almost the entire time period for the past 40-years. Among foe mineral commodities that I studied were foe asbestos m inerals, industrial grade talc, consum er talcum products, silica and titania polymorphs, vermiculite, am phibole cleavage fragments, palygorskite, attapulgite, sepiolte, and woliastonite. I have studied talc sam ples obtained from the R .T , Vanderbilt mine in New York State over this time period a s w ell. My recent studies have focused on recognition (communication) o f chem ical functionalities on foe surfaces o f minerals with receptors on mammalian ceils. My studies o f the Vanderbilt talc deposit in New York State have included many techniques employed in the study of mineral deposits, including light optica! (polarized light microscopy) and electron optical (transmission and scanning microscopy) techniques, crystal spectrometry (electron microprobe) and energy dispersive spectrometry chemistry techniques, electron diffraction studies, and both continuous-scan and step-scan x*ray diffraction techniques. I know much about the m ineralogy o f this deposit and foe nature o f the m inerals that made up its NYTAL products that entered commerce in the United States over foe past several d ecad es. Based on my studies over fo e many years I failed to find asb e sto s m inerals, of any form, in that talc. Both tremoiite and anthophyliite occur as prismatic cleavage fragmente o f crushed m assive mineral, anthophyliite occasionally occurs as intergrowths with talc, talc forms both plate and fiber (either ribbons or structural intergrowths with one of foe am phibole forms present) in the deposit Even the talc from that deposit exists in foe tridinic crystallographic form rather than the monodinic form usually described for that mineral. This last comment is induded to underscore that what h a s been stated repeatedly in the literature might b e incorrect. Tremoiite and anthophyliite exist not a s asbestiform minerals but rather a s elongate fragments produced by the milling process. They are deav& ge fragments. 1 It is important to note that a s techniques evolved over the past 20-years or so, and research into the nature o f asbestos fibers progressed, many o f the statements regarding the occurrence o f asbestiform minerals in RTV talc had to be modified, i speak for m yself now. W hat was considered to be asbestos a generation ago is rightly considered standard non-asbestos mineral today. O SH A's most recent asbestos standard correctly reflects this position. Experimental data, and epidemiological data obtained on workers from the RTV deposit have failed to show that a problem exists concerning exposure to dust generated from this talc and risk o f excess cancers (especially m esotheliom a). , Based on this constellation o f factors, including those mineratogical, experimental, and epidem iological, I would conclude that the probability that talc products from this deposit are capable o f producing mesothelioma in humans roughly approximates zero. ( cannot state never as this implies existence o f proof of a negative. If you have any question concerning any of the above statem ents please do not hesitate to contact m e. S in c e r e ly , Arthur M . Langer Ph.D . 2