Occupational silica exposure and risk of various diseases: an analysis using death certificates from 27 states of the United States
- 1Division of Surveillance, Hazard Evaluations and Field Studies, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Cincinnati, Ohio, USA
- 2Education and Information Division, National Institute for Occupational Safety and Health
- 3Division of Applied Research and Technology, National Institute for Occupational Safety and Health
- Correspondence to: Dr G M Calvert, National Institute for Occupational Safety & Health, 4676 Columbia Parkway, R-21, Cincinnati, OH 45226, USA;
- Accepted 20 June 2002
Background: Although crystalline silica exposure is associated with silicosis, lung cancer, pulmonary tuberculosis, and chronic obstructive pulmonary disease (COPD), there is less support for an association with autoimmune disease, and renal disease.
Methods: Using data from the US National Occupational Mortality Surveillance (NOMS) system, a matched case-control design was employed to examine each of several diseases (including silicosis, lung cancer, stomach cancer, oesophageal cancer, COPD, pulmonary tuberculosis, sarcoidosis, systemic lupus erythematosus, systemic sclerosis, rheumatoid arthritis, and various types of renal disease). Cases were subjects whose death certificate mentioned the disease of interest. A separate control group for each of the diseases of interest was selected from among subjects whose death certificate did not mention the disease of interest or any of several diseases reported to be associated with crystalline silica exposure. Subjects were assigned into a qualitative crystalline silica exposure category based on the industry/occupation pairing found on their death certificate. We also investigated whether silicotics had a higher risk of disease compared to those without silicosis.
Results: Those postulated to have had detectable crystalline silica exposure had a significantly increased risk for silicosis, COPD, pulmonary tuberculosis, and rheumatoid arthritis. In addition, a significant trend of increasing risk with increasing silica exposure was observed for these same conditions and for lung cancer. Those postulated to have had the greatest crystalline silica exposure had a significantly increased risk for silicosis, lung cancer, COPD, and pulmonary tuberculosis only. Finally, those with silicosis had a significantly increased risk for COPD, pulmonary tuberculosis, and rheumatoid arthritis.
Conclusions: This study corroborates the association between crystalline silica exposure and silicosis, lung cancer, COPD, and pulmonary tuberculosis. In addition, support is provided for an association between crystalline silica exposure and rheumatoid arthritis.
- ANCA, antineutrophil cytoplasmic antibody
- COPD, chronic obstructive pulmonary disease
- ESRD, end stage renal disease
- IARC, International Agency for Research on Cancer
- ICD, International Classification of Diseases
- MOR, mortality odds ratio
- NIOSH, National Institute for Occupational Safety and Health
- NOMS, National Occupational Mortality Surveillance
- PEL, permissible exposure limit
- SLE, systemic lupus erythematosus