Biopersistence of refractory ceramic fiber in human lung tissue and a 20-year follow-up of radiographic pleural changes in workers.
OBJECTIVE
The biopersistence of refractory ceramic fiber (RCF) in human lung tissue is unknown and may contribute to an association between cumulative fiber exposure and radiographic changes.


METHODS
Lung tissue fiber was analyzed for a case series of 10 RCF workers and a 20-year longitudinal chest radiograph study of 1323 workers was conducted.


RESULTS
Within lung tissue, RCF comprised 14% to 100% of fibers 5 μm or more in length and was identified up to 20 years after RCF employment. Among workers with no reported asbestos exposure, cumulative exposure of more than 63 to 110 and more than 110 fiber-months/cm was associated with radiographic pleural changes of 8.5% (odds ratio, 7.2; 95% confidence interval, 1.4 to 36.8) and 11.6% (odds ratio, 10.3; 95% confidence interval, 2.1 to 49.9), respectively.


CONCLUSIONS
Refractory ceramic fiber can persist in human lung tissue for up to 20 years and may contribute to the significant association between cumulative fiber exposure and radiographic pleural changes.
Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH, USA. james.lockey@uc.edu
James E
JE
Lockey
Victor L
VL
Roggli
Timothy J
TJ
Hilbert
Carol H
CH
Rice
Linda S
LS
Levin
Eric K
EK
Borton
Paul W
PW
Biddinger
Grace K
GK
Lemasters
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002516:Ceramics; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D019016:Mineral Fibers; D016273:Occupational Exposure; D010994:Pleura / Q000000981:diagnostic imaging*; D011859:Radiography
D019016:Mineral Fibers