Asbestos–Contaminated Vermiculite Was Shipped from Libby

Mesothelioma News

Montana Study Shows Mesothelioma Cases Follow Railroad Lines

HELENA, MT — December 16, 2005 — Many Montana residents who developed the cancer mesothelioma lived along railroad routes, according to a study by the Montana Department of Public Health and Human Resources. Mesothelioma is almost always caused by exposure to asbestos. The authors suggest that the railroads may be associated with mesothelioma victims because trains carried asbestos–contaminated vermiculite throughout the state.

Originally mined in the Montana town of Libby, vermiculite is an ore resembling mica that was used in potting soil and insulation. About 80% of the world’s vermiculite was derived from the asbestos–laden Libby mine before it was closed down in 1990.

Some of the vermiculite ore was processed in Great Falls, Montana, which is located in Cascade County, a railroad transportation hub. Cascade, Lincoln, Flathead, and Rosebud Counties had more cases of mesothelioma than would be expected based on population. Flathead and Rosebud Counties had mesothelioma cases clustered near the railroad lines. Lincoln County is the home of the contaminated Libby mine.

Mesothelioma By the Numbers

The researchers combined information from the Montana Central Tumor Registry and the Montana Death Registry. The Montana Central Tumor Registry keeps information on people with diagnosed cancers and records their age, sex, and place of residence. The Montana Death Registry is in the Office of Vital Statistics, and contains death certificates since the 1880s. Recent death certificates list age, sex, place of residence, and type of employment.

There were 200 cases of mesothelioma in Montana between 1979 and 2002, according to the study. The number of mesothelioma patients increased during this time frame, from 15 in the period from 1979 through 1982 to 55 from 1999 through 2000. This change was not fully accounted for by the 14% increase in Montana’s population. It may instead reflect the long latency period for mesothelioma, which usually takes decades to develop after initial exposure to asbestos. In line with this analysis, the average age of Montanans with mesothelioma was 70 years for men and 71 years for women. Young people did not often contract the disease.

Construction workers had high levels of mesothelioma compared to the rate of the disease in teachers or hospital workers. Montanans with mesothelioma tended to work in government, agriculture or with the railroads in larger proportions than mesothelioma sufferers in other states. As expected, Montana mine workers also had high mesothelioma rates.

Limitations of the Mesothelioma Study

The authors pointed out that although the data suggests a link between living near a railroad and developing mesothelioma, the conclusion should not be a definite one. The biggest Montana towns are near railroad lines, and one might expect that people affected with mesothelioma would live here, whether or not the railroad contributed to the spread of the disease.

For more details, see the full text of the Montana Department of Public Health study, entitled Mesothelioma in Montana, on the agency’s web site. The site also includes a report about cancer from the Montana Central Tumor Registry. (Please note that this report is a large file and make take awhile to download.) You will need to obtain a copy of Adobe Acrobat Reader to open these files. If you do not already have this software, you may download a free copy at the Adobe Acrobat web site.

For further information about asbestos exposure, see Asbestos Exposure Can Lead to Mesothelioma. If you or a loved one has been diagnosed with mesothelioma, please feel free to contact us at Brayton Purcell to learn about your legal choices. We have been handling cases involving mesothelioma and asbestos exposure for over 20 years and can provide support, information, and excellent advocacy.