Mesothelioma

The House of Representatives has decided to call a joint committee together to try to determine more accurately understand what causes mesothelioma. They decided to call the meeting after 35 new cases occured on the Range. Testimony on Tuesday morning outlined a 25-year history of attempts to address questions about mining occupations and respiratory diseases, questions that still remain today.

In addition, the Minnesota Department of Health presented its proposals for two new studies to better answer questions of whether mineral fragments and asbestos-like fibers in taconite dust are to blame for the otherwise rare fatal cancer, or if occupational asbestos exposure is strictly to blame. The first proposed study would evaluate exposure to taconite dust and asbestos in the 52 cases.

The study would also use a control, comparing mine workers with the disease to mine workers without the disease. The study requires $750,000 or more per year, according to Mary Manning from the Department of Health, who said the department is applying for federal funding, and feels they have a “compelling” case. The second study would use existing information provided by the Minnesota Pollution Control Agency to assess risks from taconite dust.

The study would consider data on the effect of different minerals on lab animals and then tailor this information to estimate the risk to humans at each mining site given its unique taconite dust composition. This research would take about one year after receipt of information from the MPCA, according to Bob Stein of the Department of Health, and could be paid for out of existing state sources.

Cleveland Cliffs is executing its own private health study of its Babbitt and Silver Bay operations to examine health risks of mining. Committee testimony and a 2003 Department of Health report outline a legacy of failed funding initiatives in the study of mining and mortality on the Range.

In the mid 1980s, a radiologist from Virginia showed an abnormally high number of thickenings on the lungs of his patients, which were further analyzed and not determined to be a community-wide health problem. However, in 1989, Range Studies Advisory Committee presented recommendations for a statewide cancer surveillance program and planning for a study of fibrous properties of minerals on the Iron Range. The department of health could not obtain funding for the Range study.

The 2003 study of 17 mesothelioma cases was part of the Occupational Respiratory Disease Information System. ORDIS used information from another research study funded by the Iron Range Resources Board, which collected the mortality information of 72,000 mining industry workers from 1930-1982. The planned mortality follow-up study could not be conducted when available resources were exhausted, according to the department.

What was to be an initial study establishing whether commercial asbestos exposure could explain the 17 reported cases of mesothelioma in the mortality data was barely finished in 2003 after $250,000 funding a year for ORDIS was cut in 2002. The study concluded that asbestos exposure could explain the 17 cases, but was only meant to be one in a sequence of steps that ultimately never developed to further target the source, according to Alan Bender of the Department of Health.

That conclusion was questioned in March, when the department re-evaluated the group of workers in the mortality study and found an additional 35 cases may not be fully explained by asbestos exposure, leading some to renew a call to further investigate taconite dust and what occupations may be most at risk. Bender claimed the department had gathered detailed occupational history for those next steps in 2003. “If we had had the continued funding I think it’s fair to say we would have the answer to the question now.”

Committee members questioned why the relatively small funding request could not be found, and did not receive a conclusive answer. Rukavina did criticize early mining companies from out east for not contributing to health studies. “‘Robber Barons, we used to call them early on’ don’t give anything back to the community. So if you think they are going to give money for a study that is unbiased I think you are sadly mistaken.”

Bob Bratulich who represents United Steel District 11, said the union was aware of the study’s shortcomings from the beginning, and was disappointed that taconite dust was not effectively addressed. Bratulich also said a lack of occupational history included in the study limited its usefulness. A question of why there has been no reported rise in asbestosis or asbestos-related lung cancers was raised by Dr. Vincent Garry, professor emeritus of the University of Minnesota medical school in the department of lab medicine pathology.

“Why is that absent, or is there information that needs to be developed?” asked Gary, “If not, we have a relatively unique situation where we have an asbestos form fiber which is capable of producing, we think, mesothelioma. To find out more about that is the question we have.” Chair Clark suggested that the joint committee visit the Range over the interim to further familiarize themselves with the stakeholders and the mines. While there is discussion in committee to include occupational information in the state’s cancer registry, no legislation currently addresses the issue.