Document 0K50qm69oeXGGJ5kOw2Or9J

November 30,2000 Via Federal Express U li PLAINTIFFS EXHIBIT CAM-269 Dr. Mary S. Wolfe NTP Board of Scientific Counselors, RoC Subcommittee BLDG 101, Room A322 111 T.W. Alexander Dr. Research Triangle Park, NC 27709 (919) 541-3971 Re: Talc Nominations -1 0 * R eport on Carcinogens Dear BSC Subcommittee Members: Luzenac America is a leading producer o f high quality talc products for both the consumer and industrial markets. As such, the National Toxicology Program's (NTP) review o f "talc not containing asbestiform fibers" is o f great consequence to Luzenac, as well as the talc industry worldwide. In conducting a thorough evaluation o f the NTP Talc Draft Background Document and the conclusions o fNTP Review Groups 1 & 2, Luzenac respectfully files the following objections with the NTP Board o f Scientific Counselors Subcommittee: 1. A critical error in the fundamental logic o f the NTP's own line o f argument categorically invalidates the NTP conclusion. 2. The NTP disregarded the unanimous finding of a comprehensive 1994 FDA workshop that there is no public health hazard associated with cosmetic talc. The FDA experts also concluded that an animal study, relied upon heavily by the NTP, was seriously flawed and not relevant to any expected human exposure. 3. The Draft Background Document makes no reference to one o f the most recent and relevant authoritative articles on this subject which supports the view that cosmetic talc is safe. 4. The Draft Background Document makes no reference to the most comprehensive study of prolonged worker exposure to talc in the workplace. Luzenac America, Inc. 9000 E. Nichols Ave. Englewood, CO 80112 USA (800) 525-TALC (8252) (303) 643-0400 Fax: (303) 643-0444 Protected Document - Subject to Protective Order CONFIDENTIAL PCPC0069933 PCPC000185967 November 30,2000 Page 2 of 6 5. The issue of talc pleurodesis was completely ignored by the NTP. 6. The Draft Background Document is confused and conflicted on the critical issue of asbestos contamination in talc products. Objection 1 A critical error in logic exists in the Draft Background Document for Talc Asbestiform and Non-Asbestiform. The error unequivocally invalidates the conclusion proposed by RG1 and RG2 that `T alc not containing asbestiform fibers is reasonably anticipated to be a human carcinogen." The error is as follows: NTP finds "the w idespread contam ination o f talc and commercial talc products with asbestiform minerals." NTP finds talc associated with epidemiological studies "m ust be assum ed...(to) contain asbestos fibers." Based on the above, NTP concludes On die carcinogenicity o f "talc not containing asbestiform fibers." (emphasis added) hi other words, the NTP reaches a conclusion on talc not containing asbestiform fibers based on its interpretation o f evidence o f the use o f talc, which talc, the NTP itself asserts, must be considered to be widely contam inated w ith asbestiform fibers. In attempting the task o f summarizing a review o f "talc containing asbestiform fibers" along with "talc not containing asbestiform fibers ", the NTP reviewers were faced with assessing the carcinogenicity o f talc in studies in which the mineral content was inadequately characterized. The reviewers responded in Section 3.3 as follows: 3.3 Talc containing asbestiform fibers and talc not containing asbestiform fibers "The lim ited inform ation in the literature on talc mineralogy and asbestos content poses a key challenge in assessing carcinogenicity." "N either occupational studies... nor the extensive literature concerning cancer and perineally applied talcum powder provide any characterization of talc mineralogy or morphology that could be used to determ ine the effects of different kinds of talc. However, because of the widespread contam ination of talc and commercial talc products with asbestiform m inerals, it must be Protected Document - Subject to Protective Order CONFIDENTIAL PCPC0069934 PCPC000185968 November 30,2000 Page 3 o f 6 assumed that "talc" Without further specification of mineralogy or morphology may contain asbestos fibers. The weight of the evidence thus indicates th at it would be prudent to regard such undifferentiated talc m aterials as carcinogenic." Section 3.3 goes on to conclude: "the evidence from studies o f ovarian cancer suggests that talcum powder is a carcinogen." By the NTP reviewers' own assertion, "talcum powder", i.e. "undifferentiated talc", "must be assumed..(to) contain asbestos fibers." Therefore, based upon the reviewers' own arguments, the NTP's conclusion cannot be valid for "talc not containing asbestos fibers." Section 3.3 also concludes: "the evidence from studies o f occupational exposure to non-asbestoscontaining talc is not sufficient to support a conclusion that this form o f talc is carcinogenic."(emphasis added) Luzenac America certainly agrees that the studies in which the talc was clearly identified For the record, Luzenac does not believe the evidence, when viewed in total, suggests that talc in any form is associated with causal factors o f ovarian cancer. It is recommended that the Board o f Scientific Counselors Subcommittee vote against the nomination o f "talc not containing asbestos fibers" as a ``reasonably anticipated human carcinogen". It is also recommended that the Board o f Scientific Counselors Subcommittee notify Review Groups 1 & 2 that their conclusion relative to talc not containing asbestos fibers is not supported by the data. The arguments and assumptions made by the reviewers in the text of the Draft Background Document unquestionably contradict their own conclusion about "talc not containing asbestos fibers." It is clear that the premise on which NTP has assessed the literature and safety issues relating to all forms o f talc is seriously faulted and cannot be used as a reasonable basis for nomination as an anticipated human carcinogen. Objection 2 The 1994 FDA/ISRTP workshop examined the NTP Lovelace study on talc and concluded that the positive talc bioassay results were likely an experimental artifact and Protected Document - Subject to Protective Order CONFIDENTIAL PCPC0069935 PCPC000185969 November 30,2000 Page 4 o f 6 a nonspecific generic response o f dust overload o f the lungs and hot a reflection of a direct activity of talc, th is was a unanimous assessment o f the workshop. Additionally, the workshop identified several key shortcomings o f the Lovelace study which further discredit its validity; the talc utilized was an ultra-fine, not cosmetic talc; the target aerosol concentrations were not maintained during 19 o f the 113 to 122 weeks o f the study; a seven-week malfunction o f the aerosol generator led to an exposure excursion o f nearly twice die intended target. Clearly, as the FDA/ISRTP experts concluded, die results o f this animal study cannot be utilized for either scientific or regulatory purposes. However, the reviewers for the Draft It is recommended that die Board o f Scientific Counselors Subcommittee reject the conclusion in Section 4.1.1.1 o f the Draft Background Document that the N IP Lovelace study "provides evidence for carcinogencity o f non-asbestiforih talc in male and female rats." Objection 3 The Draft Background Document fails to make any reference to the December 1998, "Journal o f Comments on Toxicology -T a lc -A Special Issue." This comprehensive reference source, submitted during the first public comment period on behalfo f the CTFA, was totally ignored by the reviewers o f the Background Draft Document in the preparation, discussion, and review o f talc not containing asbestiform fibers. Within the special issue, the Guest Editor* Alfred P. Wehner, DJM.D, Sc.D., F.A.T.S., presents relevant, objective reviews o f published talc studies that would have provided the NTP reviewers with invaluable insight and analysis contrary to the ultimate NTP findings. It is recommended that the Board o f Scientific Counselors Subcommittee instruct the revision o f the Draft Background Document to include reference and discussion of the "Journal of Comments on Toxicology - Talc - A Special Issue." Objection 4 The Draft Background Document fails to make any reference to the comprehensive study o f French talc workers entitled "An Epidemiological Mortality Study in the Talc Producing Industry", Wild P., Institut National de Recherche et de Security, June 2000, p i-73 (in French). A copy was submitted to NTP, preceded by an official Executive Summary in English. This study focuses on the largest talc mine and milling plant in Ihe world with mortality in the cohort tracked from January 1945 to December 1996. It is the follow-up o f a survey previously conducted on the same population, the results o f which are published Protected Document - Subject to Protective Order CONFIDENTIAL PCPC0069936 PCPC000185970 November 30,2000 Page 5 of 6 as "Survey of the respiratory health o f the workers of a talc producing factory", Wild P. et al, Occup. Environ. Med., 1995,52, p470-477. The Draft Background Document states "No available study o f workers exposed to talc includes quantitative individual-level data on the level o f exposure...." On the contrary, the data presented in these Wild P. studies do provide this, and significant evidence that talc not containing asbestos is not a human carcinogen. It Is recommended that the Board o f Scientific Counselors Subcommittee instruct the revision o f the Draft Background Document to include reference and discussion o f the evidence provided in these significant and pertinent studies o f European talc workers. PbicsjtfonJS Additional evidence that cosmetic talc is not carcinogenic can also be found in a review o f the literature relating to talc pleurodesis. Pleurodesis is the deliberate therapeutic creation o f a fibrous adhesion between the visceral and parietal layers o f the pleura. It is performed surgically by inserting talc into the pleural canal to treat recurrent spontaneous pneumothorax and other conditions. There is not a single report in die scientific literature suggesting that inhalation of cosmetic talc causes lung cancer or mesothelioma in consumers. Pleurodesis has not caused any such lesions in approximately 200 patients up to 40 years after the procedure (Chappell et al, 1979; Weissberg and Kaufman, 1986). The issue o f talc pleurodesis was completely ignored in the Draft Background Document It is recommended that the Board o f Scientific Counselors Subcommittee instruct the revision o f the Draft Background Document to include a review o f talc pleurodesis and the absence o f any association o f carcinogenicity in humans. Objection 6 The Draft Background Document provides an utterly confusing and conflicting representation o f the purity and composition o f commercial talc products, particularly as related to asbestos contamination in personal care and cosmetic talcs. Luzenac, along with the world talc community, vigorously objects to this broad misrepresentation o f talc, as it might falsely alarm consumers and regulators alike about the safety of talc. As pointed out in the Draft Background Document, it was precisely because o f the uncertainty o f the composition of talc products in the 1960's and 1970's, that the talc industry began working closely with industry trade associations and government agencies to develop talc specifications to ensure the absence o f asbestos and asbestiform fibers. As a result o f these initiatives, talc producers now routinely employ strict quality control procedures to ensure talc products can be certified to be free from asbestos and asbestiform fibers. I t is recommended that the Board o f Scientific Counselors Subcommittee instruct the revision o f the Draft Background Document to include amore definitive declaration of the composition and purity o f talc products from what was suspected prior to 1976, as Protected Document - Subject to Protective Order CONFIDENTIAL ^i PCPC0069937 PCPC000185971