Cancer mortality update with an exposure response analysis among styrene-exposed workers in the reinforced plastics boatbuilding industry

Am J Ind Med. 2018 Jul;61(7):566-571. doi: 10.1002/ajim.22853. Epub 2018 Apr 11.

Abstract

Background: There is sparse and inconsistent evidence of an association between styrene exposure and cancer.

Methods: This study examines mortality patterns in a previously studied cohort of 5201 workers employed in two Washington boat-building facilities, extending follow-up 5 years. Standardized mortality ratios (SMR) were calculated using state rates as referent. Cox regression calculated rate ratios (RR) per year employed in styrene-exposed exposed jobs.

Results: No excess deaths from lymphohematopoietic cancers (LHCs) were observed (SMR: 0.99, 95%CI: 0.74-1.30) when compared to the referent population; however, the relative risk increased with duration of employment in internal analyses. Conversely, lung cancer mortality was significantly elevated (SMR: 1.24, 95%CI: 1.08-1.41), but there was no evidence of a dose-response relationship.

Conclusion: We found evidence that occupational exposure to styrene was associated with increased LHC risk, while no such association was observed for lung cancer.

Keywords: Cox regression; exposure response; leukemia; reinforced plastics; styrene.

MeSH terms

  • Aged
  • Cohort Studies
  • Employment
  • Female
  • Hematologic Neoplasms / mortality
  • Humans
  • Leukemia / mortality
  • Lung Neoplasms / mortality
  • Lymphoma, Non-Hodgkin / mortality
  • Male
  • Manufacturing Industry*
  • Middle Aged
  • Multiple Myeloma / mortality
  • Neoplasms / mortality*
  • Occupational Exposure / statistics & numerical data*
  • Plastics
  • Proportional Hazards Models
  • Ships*
  • Styrene*
  • Time Factors
  • Washington / epidemiology

Substances

  • Plastics
  • Styrene