Deposition and clearance of chrysotile asbestos
Churg, A
HERO ID
758903
Reference Type
Journal Article
Year
1994
Language
English
PMID
| HERO ID | 758903 |
|---|---|
| In Press | No |
| Year | 1994 |
| Title | Deposition and clearance of chrysotile asbestos |
| Authors | Churg, A |
| Journal | Annals of Occupational Hygiene |
| Volume | 38 |
| Issue | 4 |
| Page Numbers | 625-633 |
| Abstract | Studies of human lungs indicate that, for virtually all types of exposure, the relative proportion of amphibole asbestos retained in the lung far exceeds the proportion in the original dust and, conversely, the relative proportion of chrysotile is far less than that in the original dust. Although amphiboles appear to accumulate in lung in proportion to exposure and chrysotile does not, failure of chrysotile deposition is probably not the reason for the disproportionate retention of amphibole fibres. The available data suggest that chrysotile is deposited in the parenchyma but is cleared extremely rapidly, with the vast bulk of fibres removed from human lungs within weeks to months after inhalation; by comparison, amphibole clearance half-lives are of the order of years to decades. The mechanisms of preferential chrysotile clearance remain uncertain, but fragmentation of chrysotile into short fibres, possibly accompanied by extremely rapid dissolution of such fibres, appears to be important in this process. Chrysotile fibres do penetrate to the periphery of the lung, so that differences in mesothelial pathogenicity of chrysotile and amphiboles in regard to mesothelioma are not caused by failure of chrysotile to reach the pleura. The theory that the tremolite contaminant rather than the chrysotile itself is the cause of 'chrysotile-induced' disease (especially mesothelioma) is consistent with the available human data, but the contrary ideas that disease is caused either by the total transient burden of inhaled chrysotile fibres or by a small, sequestered, long-retained fraction of chrysotile fibres still need to be excluded. |
| Doi | 10.1093/annhyg/38.4.625 |
| Pmid | 7978985 |
| Wosid | WOS:A1994PE88600029 |
| Url | https://search.proquest.com/scholarly-journals/deposition-clearance-chrysotile-asbestos/docview/16898831/se-2?accountid=171501 |
| Is Certified Translation | No |
| Dupe Override | No |
| Conference Location | Jersey, Channel Islands |
| Conference Name | Workshop on Health Risks Associated with Chrysotile Asbestos |
| Conference Date | November 14-17, 1993 |
| Is Public | Yes |
| Language Text | English |
| Keyword | Asbestos, Amphibole; Asbestos, Serpentine; Asbestos, Crocidolite; 12001-28-4; Asbestos, Amosite; 12172-73-5; tremolite; 14567-73-8; Index Medicus; Asbestos, Amphibole -- metabolism; Guinea Pigs; Occupational Exposure; Pleura -- metabolism; Asbestos, Amosite -- metabolism; Mesothelioma -- metabolism; Animals; Asbestos, Crocidolite -- metabolism; Time Factors; Asbestosis -- metabolism; Pleural Neoplasms -- metabolism; Textile Industry; Lung -- metabolism; Asbestos, Serpentine -- metabolism |
| Is Qa | No |