Employees, their families and people living close to 28 exfoliation sites may have been exposed to amphibole asbestos from vermiculite mined in Libby, Montana between the 1920s and the early 1990s, a new report has concluded.

In addition to the 28 exfoliation sites, the report identifies 78 additional sites in 36 states that may have been contaminated by vermiculite mined at Libby.

Vermiculite is a group of minerals with a flaky, mica–like structure, used in insulation and gardening. No research has linked serious health effects with exposure to this mineral.

However, the specific vermiculite mined in Libby and distributed across the United States was contaminated with amphibole asbestos, which has been linked to pulmonary diseases including asbestosis, lung cancer, and mesothelioma.  As many as 15 to 30 years can pass between a person’s exposure to asbestos and the time disease develops.

Workers were exposed to asbestos through a process called exfoliation, in which vermiculite is heated until it expands. Since the Libby vermiculite contained asbestos, heating released asbestos fibers into the air where they could be inhaled.

The people most at-risk for asbestos exposure include those who worked  in exfoliation facilities at some time from the 1920s to the early 1990s, people who lived in the same households with these workers and were exposed through asbestos–laden dust carried home on workers’ clothing and members of the community – particularly children – who had frequent, direct contact with vermiculite and waste rock (a by–product of exfoliation) from these facilities.

While not everyone exposed to asbestos fibers gets sick, those who do often contract asbestosis which can lead to mesothelioma, a fatal form of cancer.

Mesothelioma is one of the hardest cancers to treat—and one of the most challenging for researchers to investigate. Now a virtual bank is providing researchers with an invaluable tool for studying this disease, according to a report published in the August 13 issue of BMC Cancer.

Researchers are constantly searching for new ways to diagnose mesothelioma earlier, and to find better therapies than the limited options that currently exist. However, because malignant mesothelioma is relatively rare (2,000 to 3,000 cases are diagnosed in the United States each year), it’s often difficult for investigators who are at facilities scattered throughout the country to get the resources they need for their research.

To help, the Centers for Disease Control and Prevention (CDC), in collaboration with the National Institutes of Occupational Health and Safety (NIOSH), created the National Mesothelioma Virtual Bank (NMVB).

This bank collects, stores, and distributes mesothelioma tissue samples from various research facilities, along with blood and DNA samples and data on demographics, cancer incidence, symptoms, treatment, and recurrence. It then makes all of this information available via a web-based interface that researchers can access from wherever they are located.

Currently, the database holds more than 650 mesothelioma cases, 775 specimens, and numerous blood and DNA samples. The samples come from patients who underwent surgery, and who were recruited to participate at hospitals and physician offices around the country. Any patient who sees one of the doctors collaborating in the database is eligible to take part, provided they are 18 years old and can give informed consent. In order to protect the patients’ privacy, numbers, rather than names, have been assigned to the tissue samples and data.

The database is open to the public; however, patients and their families can only access a brief overview of each case due to HIPAA privacy regulations. NMVB’s real value is to mesothelioma researchers.

To learn more about the NMVB, visit: http://mesotissue.org

Residents living around a factory in Japan that produced asbestos products for decades have a death rate from lung cancer that is about three times higher than the national average, a new survey reveals.

The survey was the first full-scale Japanese epidemiological investigation conducted on residents living around an asbestos factory. The results indicate that lung cancer may be increasing due to pollution from asbestos particulates, and the finding is likely to bear an influence on assistance and compensation for lung cancer patients, whose relief measures in the past have been viewed as insufficient.

The survey was conducted with the cooperation of a local residents association. It analyzed responses from 1,907 people from 502 families about their health between 1992 and June 2007, while estimating the concentration of asbestos in the air by applying wind and sunlight data to air pollution dispersion models.

An elliptical area southeast of the factory was found to have the highest level of concentration. There were 234 men living in the area. The national average of deaths from lung cancer in a group this size stands at 2.72, but in actual fact 8 people — excluding those who could have inhaled asbestos at work — died, making the death rate 2.9 times higher than the national average.

The Hashima factory produced asbestos products between 1943 and 2003. Up until 1991 it had handled highly toxic amosite. In health tests, about 50 residents had a condition indicating they had inhaled asbestos. Furthermore, at least four people in the area died from mesothelioma, a type of cancer caused by asbestos exposure.