Assessment of worst-case potential airborne asbestos exposure associated with the use of cosmetic talc: application of an exponential decay model.

Talc is used in cosmetic products to confer desirable properties, such as moisture absorption and smooth texture, to the finished products. Concerns have been raised about the potential presence of asbestos in products containing cosmetic talc. Reconstruction of potential asbestos exposure from the use of cosmetic talc products (assuming a trace level of asbestos) requires consideration of consumer use patterns. Although application generally only lasts seconds, exposure theoretically may continue if the consumer remains in the immediate vicinity. Most published exposure measurements have not adequately characterized the potential for continued exposure. In this analysis, estimates and measurements of airborne asbestos fiber concentrations associated with cosmetic talc use from 10 published studies were used as inputs to an exponential decay model to estimate "worst-case" exposure during and following application. The resulting geometric mean 30-min time-weighted average (TWA) concentrations were 0.006 f/cc for both puff and shaker application, for diapering, 0.0001 f/cc (adult applying baby powder) and 0.0002 f/cc (infant), and for makeup application, 0.0005 f/cc. Application of an exponential decay model to measured or estimated asbestos concentrations associated with the use of cosmetic talc products yields a conservative means to comprehensively reconstruct such exposures. Moreover, our results support that, if a cosmetic talc powder product contained a trace level of asbestos fibers, the "worst-case" airborne asbestos exposure associated with its application is low.

Cellular immunolocalization of S100 protein within fixed tissue sections by monoclonal antibodies.

Monoclonal antibodies (MoAb) that cross-react with the shared epitopes of S100 protein have been prepared from mouse hybridoma cell lines and partially characterized. Nine of these MoAb were applied to sections of formaldehyde-fixed paraffin-embedded human tissues that were stained by immunohistochemical techniques. Three of these MoAb give uniformly and reproducibly positive staining in appropriate cell types when stained by avidin-biotin methods. Three of the MoAb were judged to be negative, although some MoAb gave inappropriate staining patterns. The three remaining MoAb showed either great heterogeneity in their staining patterns or intensities, or gave a lesser degree of reproducibility in a given tissue or neoplasm. One of the MoAb designated 15E2E2 that belonged to the first group of reproducibly staining antibodies was used to stain a larger number of normal human tissues and neoplasms. The staining that was observed appeared to recapitulate that which was previously described for conventional S100 protein antibodies. Monoclonal antibodies may, therefore, have a role in selected cases where standard microscopy is equivocal for a specific tissue diagnosis, or where independent verification of the diagnosis would be beneficial.

Angioplastic repair of a ruptured pulmonary artery aneurysm.

A 28-year-old woman had a ruptured solitary pulmonary arterial aneurysm which was successfully treated by pericardial patch graft. The etiology of the aneurysm could not be determined although the patient had had several episodes of blunt chest trauma in the past. Unusual aspects of this case include: location of the aneurysm in the intermediate portion of the left pulmonary artery within the major intralobar fissure, intrapleural rupture, preoperative diagnosis by pulmonary angiography, and an incidentally discovered histopathological abnormality of the aneurysm itself for which no satisfactory explanation has been found.