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Mesothelioma is a rare cancer that occurs in the lining of the lungs. A history of asbestos exposure at work is reported in about 70-80% of mesothelioma cases. Because higher than expected rates of mesothelioma have been reported among men in northeastern Minnesota since the late 1980s, questions have been raised about the relationship of mining to mesothelioma occurrence. The relationship of mining to other respiratory disease has also been questioned.


Initial investigation by the Minnesota Department of Health found that 58 of the mesothelioma cases are part of a cohort of 70,000 mining workers. The number of cases that occurred within this cohort of mining workers has raised concerns for taconite workers, their families and the Iron Range Community.

Factors related to mesothelioma on the Iron Range:


  • 63 cases of mesothelioma have been identified in a cohort of mining workers
  • These workers were employed in the iron mining industry at some time prior to 1982 in jobs across the Iron Range, but length of time employed has not yet been determined so risk by job and location is not known.
  • No women have been identified with mesothelioma within the taconite worker cohort
  • Mesothelioma rates in women in northeastern Minnesota appear to be less than expected.
  • Exposures in relation to the existing cases have not been investigated.


Possible factors related to mesothelioma:

Without the exposure information, we can only speculate as to the origin of the cases which could include:


  • Exposures to dust from taconite operations
  • Taconite workplace exposures from commercial asbestos use
  • Workplace asbestos exposures outside of the taconite industry
  • Non-workplace asbestos exposures
  • Other non-dust related factors