Update and comparison of cumulative fiber exposure estimates for workers in a facility expanding Libby vermiculite

<p>Introduction: Low cumulative fiber exposure (CFE) is associated with health effects in a Libby vermiculite exposed cohort. This study refines the original 1980 exposure estimates and compares the CFE results. </p><p>Methods: CFE estimates were developed using three times more industrial hygiene measurements and long-term worker’s input. New adjustments included vermiculite ore source, seasonal overtime hours, time spent in various tasks and recollection of historical dustiness.</p><p>Results: The overall mean CFE and 95% confidence interval (n=513) in 1980 (0.80 [0.7,0.9]) fiber-yr/cc was statistically similar to the CFE results in 2010 (0.74 [0.6,0.9]). The mean CFE in the lowest exposure category (> 0 - 2 fiber-yr/cc) decreased from 0.36 in 1980 to 0.22 fiber-yr/cc in 2010 (p < 0.05). Revised CFEs extended the upper bound of the range of the 1980 estimate from 28.10 to 106.31 fiber-yr/cc.</p><p>Conclusions: The range of CFE values was expanded. These estimates may be useful in understanding health outcomes of workers and residents exposed to Libby vermiculite.</p>

Name thesis:degree_name

MS

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Medicine: Epidemiology (Environmental Health)

Grantor dc:publisher

University of Cincinnati

Year dc:date

2012

Author dc:creator

• Borton, Eric K.

Contributors dc:contributor

• Lemasters, Grace

• Epidemiology
• Vermiculite
• Asbestos
• Mineral Fibers
• Cumulative Fiber Exposure
• Fiber Estimates
• Libby

Statement dc:rights

• unrestricted
• This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.

Language dc:language

English

Repository record dc:identifier

http://rave.ohiolink.edu/etdc/view?acc_num=ucin1335461760

OAI identifier oai:identifier

oai:etd.ohiolink.edu:ucin1335461760