The report doesn't identify what caused mesothelioma in the 58 miners. But it does gives health officials a bit more information about the possible source of exposure.
There were seven mining operations on the Iron Range that were active during the years when the miners were employed, according to Dr. Alan Bender, who helped compile the report. The department's new analysis shows that the sick workers had ties to six of the mines. "From a disease perspective if these diseases are conferred by mining experiences, there's nothing to indicate that there is a predilection of one area over another."
In other words the source of the cancer exposure in the workers seems to be present across the Iron Range.
There are two leading theories on what's causing higher mesothelioma rates in miners. Previous Health Department studies have suggested that commercial asbestos, found in some mining operations, could be to blame. Other researchers have speculated that fibers in taconite dust might cause the disease.
Bender says more studies are needed to pinpoint the source of exposure. In particular he says researchers hope to learn more about the specific jobs the miners held. That information is vital to understanding what has happened on the Range, Commissioner of Health Sanne Magnan says.
"What's the work experience that they have in comparison say to a group of miners that does not have mesothelioma? What would that tell us? What would that show us?"
The Health Department has partnered with the University of Minnesota to launch future studies of the miners. The arrangement was established earlier this year shortly after news reports revealed that the previous Commissioner of Health, Dianne Mandernach, had delayed the release of information about the mesothelioma cases in miners for a year.
The new information about the miners doesn't answer many of the public's questions. But Dean John Finnegan Jr.,of the U of M School of Public Health, commends the department for sharing it anyway.
"Once in a while you want to err on the side of openness. Given the very delicate politics surrounding this, you want to be able to provide people with as much information as we can."
University and Health Department researchers have put together proposals for three different studies that will look at work experiences in the mining industry, along with respiratory health among the workers and their overall causes of death compared to the rest of the population, Finnegan says. He estimates researchers will ask for $5.5 to $6 million in funding from the Legislature to be spent over five years.