[Mortality analyses for tungsten miners].

OBJECTIVE

To investigate the mortality from main causes of death in 6 tungsten miners and explore the effects of cumulative dust exposure on standardized mortality ratios (SMRs) from main causes.

METHODS

A cohort of 18027 workers registered in the employment record from 6 tungsten mines located in Hunan and Jiangxi province and working for at least 1 year was identified for this study. SMRs were calculated based on Chinese national mortality. Trend analysis was used to analyze the effect of cumulative dust exposure on SMRs of main causes of death.

RESULTS

The cohort was followed up from 1972 to 2003 with an accumulative of 470 722.21 person-years. A total of 6135 workers died, and the mortality was 13.03 per thousand. Cardiovascular disease, respiratory disease, malignant neoplasm and pulmonary tuberculosis accounted for 79.32% of all death. The mortalities of all-causes, pneumoconiosis, pulmonary tuberculosis, nasopharyngeal carcinoma, infectious disease, respiratory disease, cardiovascular disease and liver cancer were found to be significantly higher than the national average level. Positive dose-response relationship between SMRs and cumulative dust exposure was observed in all-causes, pneumoconiosis, pulmonary tuberculosis, respiratory disease, cardiovascular disease (P < 0.01).

CONCLUSION

The mortality from main causes of death for the dust-exposed workers are higher than that for non dust-exposed workers. Positive dose-response relationships are observed between cumulative dust exposure and SMRs from all-causes, respiratory disease (including silicosis), pulmonary tuberculosis and cardiovascular disease.