Absence of radiographic asbestosis and the risk of lung cancer among asbestos-cement workers: Extended follow-up of a cohort

Authors

  • Murray M. Finkelstein PhD, MD

    Corresponding author
    1. Department of Family and Community Medicine, University of Toronto, Toronto, Ontario, Canada
    • Granovsky-Gluskin Family Medicine Centre, Mt Sinai Hospital, 60 Murray Street, 4th Floor, Toronto, ON, Canada M5T 3L9.
    Search for more papers by this author

  • Competing interests: Dr. Finkelstein has on occasion, since 2004, served as an expert witness in asbestos litigation.

Abstract

Background

It has been a matter of controversy whether there is an increased risk of lung cancer among asbestos-exposed workers without radiographic asbestosis. A previous study of lung cancer risk among asbestos-cement workers has been updated with an additional 12 years of follow-up.

Methods

Subjects had received radiographic examination at 20 and 25 years from first exposure to asbestos. Radiographs were interpreted by a single National Institute of Safety and Health (NIOSH)-certified B-reader using the 1971 International Labor Office (ILO) Classification of the pneumoconioses as reference standard. Asbestosis was defined as an ILO coding of 1/0 or higher. Standardized Mortality Ratios (SMRs) were calculated using the general population of Ontario as reference.

Results

Among asbestos-cement workers without radiographic asbestosis at 20 years latency the lung cancer SMR was 3.84 (2.24–6.14). Among workers without asbestosis when examined at 25 years latency the SMR was 3.69 (1.59–7.26).

Conclusions

Workers from an Ontario asbestos-cement factory who did not have radiographic asbestosis at 20 or 25 years from first exposure to asbestos continued to have an increased risk of death from lung cancer during an additional 12 years of follow-up. Am. J. Ind. Med. 53:1065–1069, 2010. © 2010 Wiley-Liss, Inc.

Ancillary