Diagnosis, Risks, Asbestos Hazards

A proper diagnosis is essential to a treatment plan.

In Sweden, doctors followed the course of 85 patients with pleural mesothelioma. They concluded that the survival of mesothelioma patients was more dependent on pre-treatment factors, such as the quality of the diagnosis, than on the effect of remedial interventions. It is critical to determine the cell type of the mesothelioma. There are three classes of mesothelioma tumors. Research indicates that patients with "epithelial" mesothelioma tend to survive much longer than those with sarcomatoid mesothelioma. The study points up the importance of making sure that biopsies be performed correctly, that sufficient tumor and tissue are available, and that the specimens are evaluated by trained pathologists. Chest 1996; 109(1): 109-14.

To ensure a quality diagnosis (either ruling out or confirming tumor), doctors recommend the use of a thora scope with a video camera. This is especially important where the cytology (or study of the fluid for cancer) is negative. Bronchoscopy and needle biopsy do not always obtain sufficient tissue upon which a reliable diagnosis can be made. In Italy, chest doctors concluded that diagnostic thoracoscopy under local anesthesia in pleural effusions is a safe procedure with a very high degree of diagnostic accuracy. Casalini et al., Eur Respir J 1994;7 (suppl 18):443s.

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Asbestos Death Count Will Peak in 2020

The number of mesothelioma deaths in the United Kingdom is predicted to peak in the year 2020 at between 2700 and 3300 deaths. The largest high risk group for mesothelioma in England are construction workers, especially plumbers, pipefitters, carpenters and electricians. Mesothelioma deaths will continue to increase for at least 15 and more likely 25 years. For asbestos-exposed workers born in the 1940's, mesothelioma may account for 1% of all deaths. Peto, et al., Lancet (Mar. 1995).

Note: England began regulating the use of asbestos fibers in the workplace in the 1930's, whereas the US did not begin seriously regulating asbestos until 1973.

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Shipyard Workers Pay Attention!

Workers who were exposed to asbestos at the Pearl Harbor Naval Shipyard (PHNS) have a ten-fold greater chance of developing mesothelioma than non-PHNS workers. Sinks, Epidemiology (Jul. 1994).

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Fire Burns, Ice is Cold, and Asbestos Causes Mesothelioma

Asbestos companies frequently argue that mesotheliomas can be caused by factors other than asbestos. They argue that only 80% of mesotheliomas are definitely caused by asbestos. The others, they contend, are due to genetics, other chemicals or radiation.

However, several leading experts, such as Dr. Samuel Hammar, author of a textbook called Pulmonary Pathology that weighs about 30 pounds, believe that the number of mesotheliomas attributed to asbestos are under reported because the doctors generally do not have the time or expertise to take a thorough occupational exposure history. Additionally, many patients are simply unaware of the levels of asbestos fibers in their home and work environments. A recent study in Sweden confirmed that doctors were lax in attributing mesotheliomas to occupational asbestos exposures. The article concludes: "physicians must give more priority to exposure histories in patients with pleural mesotheliomas." Andersson, Am. J. Ind. Med. (Apr. 1995).

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How Toxic is Asbestos?

According to the Occupational Safety and Health Administration, as reported in the Federal Register in 1986:

"OSHA is aware of no instance in which exposure to a toxic substance has more clearly demonstrated detrimental health effects on humans than has asbestos exposure. The diseases caused by asbestos exposure are life-threatening or disabling. Among these diseases are lung cancer, cancer of the mesothelial lining of the pleura and peritoneum, asbestosis, and gastrointestinal cancer. Of all of the diseases caused by asbestos, lung cancer constitutes the greatest health risk for American asbestos workers. Lung cancer has been responsible for more than half of the excess mortality from asbestos exposure in some occupational cohorts."

DEPARTMENT OF LABOR, Occupational Safety & Health Administration, Federal Register, Vol. 51, No. 119, Friday, June 20, 1986, Rules and Regulations, pg. 22615

Owens Corning Fiberglas Corp acknowledged in 1966 that Dr. Irving Selikoff reported that as little as one asbestos fiber in the body can cause cancer. Memo dated 8/8/1966.

Dr. Selikoff studied the mortality of 17,800 asbestos insulation workers from 1967 to 1986. He found an alarming increase in the number of asbestos-related deaths because of cancer not only in the lungs and linings, but also in other organs, such as the gastrointestinal tract, larynx, pharynx, kidney, pancreas, gallbladder and bile ducts.

Selikoff, "Asbestos-Associated Deaths among Insulation Workers in the United States and Canada, 1967-1987", reprinted in The Third Wave of Asbestos Disease: Exposure to Asbestos in Place , Annals of the New York Academy of Sciences, vol. 643 (1991).

All asbestos fiber types cause mesothelioma, including chrysotile asbestos, which is the most prevalent form of asbestos used in North America. According to Dr. William Nicholson, there is no difference in the potency of chrysotile and amosite for producing mesothelioma. Crocidolite asbestos, which was seldom used in the U.S., may carry the greatest potency for causing mesothelioma.