Asbestos Linked to Throat Cancer
Panel's Conclusion Could Affect Congressional Debate Over Compensation Fund
WebMD News Archive
June 6, 2006 -- A government expert panel on Tuesday added cancercancer of the larynx to the list of ailments directly linked to asbestos exposure but said there was less evidence tying the mineral to a variety of other cancers.
The conclusion means that thousands more workers exposed to asbestos could qualify for compensation from a fund under debate in Congress. But lawmakers are still far from agreement on the proposed $140 billion fund, and it looks increasingly unlikely that Congress will finalize it this year.
An Institute of Medicine (IOM) panel concluded Tuesday that large-scale studies show a “causal relationship” between asbestos exposure and cancer of the larynx, a part of the throat containing the vocal cords.
Results from 34 studies show that people exposed to asbestos have an average 40% greater chance of laryngeal cancer than those with no exposure, the committee concluded. People with high exposure -- including miners and some construction and textile workers -- had up to double to triple the risk.
The panel also found evidence linking asbestos to cancer of the stomach, upper throat, colon, and rectum. But it said that studies were not strong enough to conclusively point to asbestos as a cause.
“There’s some evidence showing greater risk in those who are exposed, but there’s still substantial uncertainty,” Jonathan Samet, MD, chair of the IOM panel, tells WebMD.
Asbestos was used for decades in a variety of industrial products, including insulation, construction materials, fire retardants, and tiling. Exposure to asbestos was conclusively linked more than 40 years ago to common lung cancerlung cancer and a rarer form of lung cancer known as mesothelioma.
Asbestos consists of microscopic fibers that lodge in airway cells causing chronic inflammation, which in some cases leads to malignancy.
Asbestos fibers also enter the gastrointestinal tract, though it is unclear how they may “target” cells in the stomach or colon, Samet says.
“We don’t have a clear picture of how or if the asbestos actually enters cells,” says Samet, who is chief of epidemiology at the Bloomberg School of Public Health at Johns Hopkins University.