Document NEbG3ebbaa6M0eRv71zegQDrR

WORLD HEALTH ORGANIZATION INTERNATIONAL AGENCY FOR RESEARCH ON CANCER IARC Monographs on the Evaluation of Carcinogenic Risks to Humans VOLUME 93 Carbon Black, Titanium Dioxide, and Talc LYON, FRANCE 2010 PLAINTIFF'S EXHIBIT CAM-33 CPC-BCALTRSCPT00001176 CPC-BCALTRSCPT00001177 TALC 303 Kauppinen et al. (2002) described the prevalence o f exposure to tale among workers in the on-machine coating of paper. In total, 25 departments were assessed: in 60% o f the departments, more than 5% of the workers were exposed to talc, with a median prevalence of exposure of 51-90%. 'The median level o f exposure was assessed as medium (0,6-2 mg/m3) by a team of occupational hygienists, Pooley and Rowlands (1975) examined talc imported into the United Kingdom. These talcs were used in a variety of industries, including cosmetics. Only one of the samples examined contained tremolite (>30%). [The number of samples examined and their use were not given. The electron micrograph of the sample identified as tremolite and the concentration of tremolite are consistent with the Gouvemeur District New York State talc, which is unlikely to have been used in cosmetics,] All other elongated particles detected in the samples were identified as laths or rolled sheets of talc, chlorite or sepiolite (several samples). 1.3.3 Consumer exposure (a) Mineralagical characterization Two studies that were conducted between 1968 and 1977 examined the mineralogy of consumer talc in the USA. Cralley et al. (1.968) examined 22 cosmetic talc products that were purchased off the shelf for particles >5 pm with a 3:1 or greater aspect ratio (diametenlength) and found that on average 19% of the particles met these dimensional criteria. [No additional information was provided on the source of the talc products, but the Working Group noted that the authors were located in Cincinnati, OH, USA.] The authors concluded that these `fibres3 were predominantly talc, but suggested that some may have been anthophyllite, tremolite, pyrophyllite or chrysotile, [The Working Group noted that no data were provided to support this statement. The statement was based only on the fact that these minerals have been reported to occur in some talc deposits.] Using X-ray diffraction, quartz was found at a level of 0.2- 53.4% in these samples. No limit of detection was given, but the lowest concentration reported was 0.2 wt%. Analysis for other minerals was not carried out. Rohl et al (1976) examined 20 body powders, baby powders and facial talcums and one pharmaceutical talc, all o f which were purchased at retail stores in New York City between 1971 and 1975. Based on X-ray diffraction, optical microscopy and transmission electron microscopy, the concentration of tremolite, anthophyllite and quartz was estimated and the presence of several other minerals was established (see Tables 1.14 and 1.15). One of the 21 samples was composed entirely of cornstarch and one contained primarily pyrophyllite and only a small amount of talc. Quartz was present in nine of the 21 samples, tremolite was reported in nine, anthophyllite in seven and serpentine in two samples. Chrysotile was confirmed by transmission electron microscopy in these samples, but no estimates of the concentrations were provided. Krause (1977), in a review o f this study, pointed out that the overlap of the X-ray diffraction patterns of tremolite and CPC-BCALTRSCPT00001178 304 IARC MONOGRAPHS VOLUME 93 anthophyllite makes accurate estimation of their concentration by this method impossible. A similar problem was pointed out for estimates of the concentration of quartz because of overlap with several talc peaks. [The Working Group believed that these criticisms were reasonable and that little reliance can be placed on the reported concentration of tremolite or anthophyllite. The Working Group also noted that Rohl et al (1976) stated that their methodology did not distinguish between asbestos and non-asbestifomr mineral fragments. In addition, the representativeness of these samples for other countries or for other areas of the USA is unclear.] Table 1.14. Concentrations of minerals in 20 samples of body powders, baby powders and facial talcums and one sample of pharmaceutical talc Mineral No. of samples Concentration range (wt%) Quartz Tremolite" Anthophyllite" Chrysotile 9 9 7 2 1.6-35.1 0.1-10.3 2.1-11.4 <0.5b From Rohl et al. (1976) " Six samples contained both minerals, which resulted in uncertainty about the absolute concentrations given for each mineral. bVisual estimates by transmission electron microscopy were given as 0.250.5%, but no methodology was provided. Table 1.15. Qualitative measurements of minerals other than anthophyllite, chrysotile, quartz or tremolite in 20 samples of body powders, baby powders and facial talcums and one sample of pharmaceutical talc Mineral No. of samples in which the mineral was present Talc Chlorite Calcite Phlogopite Pyrophillite Dolomite Kaolin 20' 16' 8' 3*1 21 1' 1' From Rohl et al. (1976) 1 Talc was the major mineral in 19 of the 20 samples. bPresent in quantities above trace amounts CPC-BCALTRSCPT00001179