Asbestos Exposure, Part 2

by National Cancer Institute

(Page 2 of 2)

5. How great is the risk?

Not all workers exposed to asbestos will develop diseases related to their exposure. The risk of developing asbestos-related diseases varies with the type of industry in which the exposure occurred and with the extent of the exposure. Asbestos that is bonded into finished products such as walls and tiles poses no risk to health as long as it is not damaged or disturbed (for example, by sawing or drilling) in such a way as to release fibers into the air. When asbestos fibers are set free and inhaled, however, exposed individuals are at risk of developing an asbestos-related disease.

In addition, different types of asbestos fibers may be associated with different health risks. For example, results of several studies suggest that amphibole forms of asbestos may be more harmful than chrysotile, particularly for mesothelioma. Even so, no fiber type can be considered harmless, and people working with asbestos should always take proper safety precautions to limit exposure.

6. How does smoking affect risk?

Many studies have shown that the combination of smoking and asbestos exposure is particularly hazardous. Smokers who are also exposed to asbestos have a greatly increased risk of lung cancer. However, smoking combined with asbestos exposure does not appear to increase the risk of mesothelioma.

There is evidence that quitting smoking will reduce the risk of lung cancer among asbestos-exposed workers. People who were exposed to asbestos on the job at any time during their life or who suspect they may have been exposed should not smoke. If they smoke, they should stop.

7. Who needs to be examined?

Individuals who have been exposed (or suspect they have been exposed) to asbestos fibers on the job or at home via a family contact should inform their physician of their exposure history and any symptoms. Asbestos fibers can be measured in urine, feces, mucus, or material rinsed out of the lungs. A thorough physical examination, including a chest x-ray and lung function tests, may be recommended. It is important to note that chest x-rays cannot detect asbestos fibers in the lungs, but they can help identify any lung changes resulting from asbestos exposure. Interpretation of the chest x-ray may require the help of a specialist who is experienced in reading x-rays for asbestos-related diseases. Other tests also may be necessary.

As noted earlier, the symptoms of asbestos-related diseases may not become apparent for many decades after exposure. If any of the following symptoms develop, a physical examination should be scheduled without delay:

• Shortness of breath;
• A cough or a change in cough pattern;
• Blood in the sputum (fluid) coughed up from the lungs;
• Pain in the chest or abdomen;
• Difficulty in swallowing or prolonged hoarseness; and/or
• Significant weight loss.

8. How can workers protect themselves?

Employers are required to follow regulations dealing with asbestos exposure on the job that have been issued by the Occupational Safety and Health Administration (OSHA), the Federal agency responsible for health and safety regulations in maritime, construction, manufacturing, and service workplaces. The Mine Safety and Health Administration (MSHA) enforces regulations related to mine safety. Workers should use all protective equipment provided by their employers and follow recommended work practices and safety procedures. For example, National Institute of Occupational Safety and Health (NIOSH)-approved respirators that fit properly should be worn by workers when required.

Workers who are concerned about asbestos exposure in the workplace should discuss the situation with other employees, their employee health and safety representative, and their employers. If necessary, OSHA can provide more information or make an inspection.

9. Is there a danger of nonoccupational exposure from the environment and products contaminated with asbestos fibers?

Asbestos is so widely used that the entire population has been exposed to some degree. Air, drinking water, and a variety of consumer products all may contain small amounts of asbestos. In addition, asbestos fibers are released into the environment from natural deposits in the earth and as a result of wear and deterioration of asbestos products. Disease is unlikely to result from a single, high-level exposure, or from a short period of exposure to lower levels of asbestos.

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