A report on specific details involving the 58 Minnesota Iron Range miners who have died from mesothelioma has raised more questions than answers. The preliminary data shows a large variation in how long the miners were employed and their possible sources of exposure.
The report was prepared by the Minnesota Department of Health in order to begin more detailed studies as to what is responsible for the exorbitant number of mesothelioma cases. Further studies will be in conjunction with the University of Minnesota School of Public Health.
Here are some of the preliminary results:
- Almost 25% of the men were employed for less than one year with one employed for just over a month. More than half of the men worked for less than five years and just over one fourth of the miners worked for 30 years or more.
- In 57 of the 58 cases, mesothelioma was diagnosed more than 30 years after they had been employed at the mine. In five of the cases the interval between employment and diagnosis was 60 years.
- The 58 miners are among a pool of up to 72,000 people who worked in the iron range between the 1930s and 1982.
One miner believes the reason that so many of the cases worked in the mines for less than a year is because of the probationary period for new employees. He said that new employees were responsible for jobs that would have included a much greater exposure to dust than employees who had been there longer.
The issue of mesothelioma and mining emerged just over a year ago when it was revealed that cases of mesothelioma occurred at twice the national average for that part of the state. There has been some concern over taconite ore because it is shaped similar to asbestos fibers.
Three studies are planed to better understand the relationship between mining and mesothelioma. The first will look at each of the 58 cases in more detail to try and find a specific cause while the second will look at whether mining has any affect on the respiratory function of current and former miners. The third will compare other dust exposure cases to those in the iron range to try and find any similarities. The studies are waiting legislative funding which is expected to be approved soon.