Occupational Exposure

Exposure to asbestos fibers has been recognized as an occupational health hazard since the early 20th century. Numerous epidemiological studies have associated occupational exposure to asbestos with the development of pleural plaques, diffuse pleural thickening, asbestosis, carcinoma of the lung and larynx, gastrointestinal tumors, and diffuse malignant mesothelioma of the pleura and peritoneum. Asbestos has been widely used in many industrial products, including cement, brake linings, gaskets, roof shingles, flooring products, textiles, and insulation.

Commercial asbestos mining at Wittenoom, Western Australia, occurred between 1937 and 1966. The first case of mesothelioma in the town occurred in 1960. The second case was in 1969, and new cases began to occure more frequently after that. The lag time between initial exposure to asbestos and the development of mesothelioma varied from 12 years 9 months up to 58 years. A cohort study of miners employed at the mine reported that 85 deaths attributable to mesothelioma had occurred by 1985. By 1994, 539 reported deaths due to mesothelioma had been reported in Western Australia.

Occupational exposure to asbestos in the United States mainly occurs when people are maintaining buildings that already have asbestos. Approximately 1.3 million US workers are exposed to asbestos annually; in 2002, an estimated 44,000 miners were potentially exposed to asbestos.

Past Direct Occupational Exposures to Asbestos (Occupations):

• Auto mechanics
• Boilermakers
• Bricklayers
• Building inspectors
• Carpenters
• Demolition workers
• Drywallers
• Electricians
• Floor covering workers
• Furnace workers
• Glaziers
• Grinders
• Hod carriers
• Insulators
• Ironworkers
• Laborers
• Libby vermiculite exfoliation plant workers
• Longshoremen
• Maintenance workers
• Merchant marines
• Millwrights
• Operating engineers
• Painters
• Pipefitters
• Plasterers
• Plumbers
• Roofers
• Refinery workers
• Sheet metal workers
• Shipyard workers
• Steamfitters
• Tile setters
• U.S. Navy personnel
• Welders

Past Direct Occupational Exposures to Asbestos (Businesses):

• Asbestos product manufacturing (insulation, roofing, building materials)
• Automotive repair shops (especially those that involve repair of brakes, clutches)
• Construction companies
• Maritime companies
• Mining companies
• Offshore rust removal businesses
• Oil refineries
• Power plants
• Railroads
• Manufacturers of sand or abrasives
• Shipbuilders, ship lines, and shipyards
• Steel manufacturers
• Tile installation

Today in the United States, most occupational exposures occur during repair, renovation, removal, or maintenance of asbestos-containing products installed years ago. The Occupational Safety and Health Administration (OSHA) has estimated that 1.3 million employees in construction and general industry are exposed to asbestos on the job during these above-mentioned activities.

Currently, the people most heavily exposed to asbestos in the United States are those in construction trades. This population includes an estimated 1.3 million construction workers as well as workers in building and equipment maintenance [American Thoracic Society 2004]. Because most asbestos was used in construction, and most asbestos produced is still used in this industry, risk to these workers can be considerable if the hazard is not recognized and Occupational Safety and Health Administration (OSHA) standards are not enforced.

* Source: NIOSH 2003; 2008