Bernstein D.M., Rogers R., Sepulveda R., Kunzendorf P., Bellmann B., Ernst H., Phillips J.I.
Evaluation of the deposition, translocation and pathological response of brake dust with and without added chrysotile in comparison to crocidolite asbestos following short-term inhalation: Interim results
Consultant in Toxicology, 1208 Geneva, Switzerland; Rogers Imaging, Needham, MA 02494, United States; GSA Gesellschaft für Schadstoffanalytik mbH, D-40882 Ratingen, Germany; Fraunhofer Institute for Toxicology and Experimental Medicine, D-30625 Hannover, Germany; National Institute for Occupational Health, National Health Laboratory Service, South Africa; Department of Biomedical Technology, Faculty of Health Sciences, University of Johannesburg, South Africa
Bernstein, D.M., Consultant in Toxicology, 1208 Geneva, Switzerland; Rogers, R., Rogers Imaging, Needham, MA 02494, United States; Sepulveda, R., Rogers Imaging, Needham, MA 02494, United States; Kunzendorf, P., GSA Gesellschaft für Schadstoffanalytik mbH, D-40882 Ratingen, Germany; Bellmann, B., Fraunhofer Institute for Toxicology and Experimental Medicine, D-30625 Hannover, Germany; Ernst, H., Fraunhofer Institute for Toxicology and Experimental Medicine, D-30625 Hannover, Germany; Phillips, J.I., National Institute for Occupational Health, National Health Laboratory Service, South Africa, Department of Biomedical Technology, Faculty of Health Sciences, University of Johannesburg, South Africa
Chrysotile has been frequently used in the past in manufacturing brakes and continues to be used in brakes in many countries. This study was designed to provide an understanding of the biokinetics and potential toxicology following inhalation of brake dust following short term exposure in rats. The deposition, translocation and pathological response of brake dust derived from brake pads manufactured with chrysotile were evaluated in comparison to the amphibole, crocidolite asbestos. Rats were exposed by inhalation 6h/day for 5days to either brake dust obtained by sanding of brake-drums manufactured with chrysotile, a mixture of chrysotile and the brake dust or crocidolite asbestos. No significant pathological response was observed at any time point in either the brake dust or chrysotile/brake dust exposure groups. The long chrysotile fibers (>20μm) cleared quickly with T1/2 estimated as 30 and 33days, respectively in the brake dust and the chrysotile/brake dust exposure groups. In contrast, the long crocidolite fibers had a T1/2>1000days and initiated a rapid inflammatory response in the lung following exposure resulting in a 5-fold increase in fibrotic response within 91days. These results provide support that brake dust derived from chrysotile containing brake drums would not initiate a pathological response in the lung following short term inhalation. © 2014 The Authors.
amphibole; chrysotile; crocidolite; air monitoring; air sampling; animal experiment; animal tissue; article; atmospheric deposition; clinical examination; connective tissue; controlled study; diaphragm; dust; dust exposure; ecotoxicology; exhaust gas; histopathology; inhalation; lung parenchyma; nonhuman; rat; tissue preparation; Rattus; Amphibole asbestos; Brake dust; Chrysotile; Inhalation toxicology; Lung/pleura; Pathology; Animals; Asbestos, Crocidolite; Asbestos, Serpentine; Asbestosis; Disease Models, Animal; Dust; Half-Life; Industry; Inhalation Exposure; Lung; Male; Materials Testing; Motor Vehicles; Occupational Diseases; Physicochemical Phenomena; Protective Devices; Rats; Rats, Wistar; Respiratory Mucosa; Tissue Distribution; Toxicity Tests, Acute