Sheet Metal Workers Face Higher Risk of Asbestos-Related Disease, Study Says
Tuesday, August 18th, 2009By Wade Rawlins
Sheet metal workers are at higher risk of asbestos-related diseases, according to a new study by researchers at Duke University and the Center for Construction Research and Training in Silver, Spring Maryland.
The study, published in the August issue of the American Journal of Industrial Medicine, found “a statistically significant excess mortality” for mesothelioma, asbestosis and cancers of the pleura or lining of the chest and abdomen. Mesothelioma is a rare cancer nearly always related to asbestos exposure.
Researchers, led by John Dement of Duke’s Division of Occupational and Environmental Medicine, analyzed the overall mortality patterns of 17,345 workers with 20 years or more in the sheet metal trade who had taken part in a long-running asbestos disease-screening program. That provided the researchers chest x-rays and health records of the workers. The researchers also looked at effects of asbestos exposure, smoking and asbestosis on the risk of lung cancer.
Sheet metal workers fabricate and install heating and air conditioning ductwork, produce appliances such as refrigerators and air conditioners and work in shipyards and the railroad industry.
For many years, they were sporadically exposed to asbestos that was being sprayed on surfaces for fire-proofing until that method of application was banned in 1973. Today, use of asbestos is strictly regulated and workers’ greatest potential for exposure is during renovation of older asbestos-insulated ventilation systems.
The workers in the study had been involved in the sheet metal trade on average about 32 years, and nearly all were white men. Their average age was about 57 years old.
The group’s overall mortality was lower than the U.S. population’s standardized death rate, the researchers said, suggesting the workers were a hardy lot.
Still, the researchers found significantly higher risk of certain asbestos-related diseases including mesothelioma, lung cancer and asbestosis. The analysis also found a significantly higher risk of lung cancer and cardio obstructive pulmonary disease among those workers in whom tests had detected changes to functional in their lungs.
The researchers said the study offered additional evidence that workers who experienced periodic exposure to asbestos are at increased risk of asbestos-related diseases. Even workers whose x-rays had not revealed asbestosis or abnormalities in the lining of the lungs had significantly increased risk of mesothelioma and cancers of the pleura, the study found.
The Sheet Metal Workers International Association and the Sheet Metal and Air Conditioning National Association established the screening program in 1985 to examine the health hazards in the sheet metal industry in the United States and Canada. More than 18,000 workers took part in the screening program from 1986 to 2004.
###
