Taconite not source of asbestos exposure

Iron Range asbestos-related health problems were probably from commercial asbestos and not from taconite, the Health Department says

By John Myers, Duluth News-Tribune

Steelworkers on Minnesota's Iron Range who developed lung disease from exposure to asbestos likely got that exposure from boilers, furnaces and pipes - commercial asbestos - and not from fibers in taconite.

That's the finding of a draft report released Wednesday by the Minnesota Department of Health after four years of studying Iron Range taconite plant and mine workers.

The draft report's executive summary was released after the Duluth News Tribune and Minneapolis Star Tribune recently filed state Data Practices Act requests for the information. The full report will be available next month.

The source of the exposure is of little consolation to workers who are suffering from diseases such as mesothelioma and asbestosis or families of workers who already have died.

But the distinction of where the asbestos exposure came from is important because it sheds more light on whether some taconite itself carries cancer-causing fibers.

History
Asbestos-like fibers in taconite from eastern Mesabi Iron Range mines were the basis of the state's most infamous environmental battle. In 1974, a federal judge ordered Reserve Mining Co. to stop dumping taconite tailings into Lake Superior because of the asbestos-like iron silicate fibers it contained.

As early as 1985, a panel of international experts determined that some Iron Range men had been exposed to asbestos and urged the state to pinpoint the source.

The issue gained attention again in 1997 when state health statisticians reported that the mesothelioma rate in men in Northeastern Minnesota was 70 percent higher than the state average. In the 1990s, 40 cases of the disease were detected in Northeastern Minnesota, 16 more than researchers would have expected. That number has since increased to 100 percent above the state average, state health officials say.

Because the mesothelioma rate wasn't higher in women, it was believed that on-the-job exposure was causing the lung ailment, which is generally rare and which is caused only by exposure to asbestos.

Conwed not the Culprit
The disease usually shows itself in men older than 50 who had asbestos exposure 30 years or more before diagnosis. Part of Northeastern Minnesota's high rate was attributed to the Conwed plant in Cloquet, which processed asbestos tiles and which employed 5,000 people from the 1958 to 1974. Hundreds of those workers were later diagnosed with mesothelioma, especially those who smoked when they worked there, and many have since died.

Still, the Conwed asbestos exposure alone didn't fully explain the region's high mesothelioma rate. Health experts immediately looked at the mining industry as a likely exposure source.

According to the study, of 17 Iron Range miners studied who developed mesothelioma between 1988 and 1996, 11 had probable exposure to commercial asbestos on the job and another four had possible exposure. Some men had the exposure while working in mine-related jobs; others had exposure while working other jobs years ago.

"...Commercial asbestos exposure, rather than taconite dust, is the most likely explanation for the occurrence of mesothelioma in men employed in the mining industry," the draft report concludes.

But because of the likelihood that so many men did come in contact with commercial asbestos in the processing plants or mines, the report notes that "Iron miners as a group are at risk of developing mesothelioma and possibly other asbestos-related diseases. Because of the long latency of asbestos-related diseases, these risks will continue into the future even in the absence of ongoing exposure."

Miners Disagree
Joe Scholar, a retired supervisor from LTV Steel Mining Co. in Hoyt Lakes, said the Department of Health study is flat wrong. He and others insist taconite is the asbestos source. Scholar, 79, suffers from asbestos plural lung disease.

"Their report is a lie. My records show completely different, that the asbestos is in the taconite dust," Scholar said. "We've known since 1957 that there was asbestos in the taconite concentrate."

Scholar was instrumental in convincing Iron Range lawmakers to fund the health study. But he said the Department of Health never looked closely at taconite as the culprit and never did an analysis of the ore.

Moreover, Scholar said, because it takes 40 years or more for some asbestos-related disease to surface, many miners just now may be showing signs of ill health. The eastern Range taconite plants were built in the 1950s.

Buddy Ferguson, a Minnesota Department of Health spokesman, said the agency wouldn't comment on the draft report at this time. "We had promised the members of the (community) advisory committee that we'd make a presentation of the findings to them before it was released to the public," Ferguson said. That could be in early March.

Critics Pan State
Some critics have said the state hasn't acted fast enough or with enough money to fully study the issue, including Twin Cities attorney Grant Merritt called for a full-fledged health study of all current and former miners, whether they show signs of disease or not.

The report itself concedes that the study "does not answer many of the questions about the health and safety of iron miners." The executive summary promises the full report will describe "several options for future efforts, addressing different questions about mesothelioma in Northeastern Minnesota and across the state, occupational respiratory disease in general, and the health of iron miners."

The report will be a major component next month at a Twin Cities symposium of mining, health and geology experts. They're meeting to revisit the scientific data on eastern Mesabi Range taconite and asbestos-related health issues.

The report issued Wednesday, and any conclusions from the symposium, might help supporters of efforts to deregulate taconite tailings from eastern Range mines. There's growing support to use the tailings in road construction and other projects in place of aggregate. Tailings from western Range mines, not suspected of holding asbestos-like fibers, already are being used in construction.

Larry Sundberg, St. Louis County epidemiologist, wasn't part of the state study, but said the report makes sense. If taconite was the source of exposure that caused the disease, considering the amount of taconite dust spread across the region, there would have been many more people affected, Sundberg said. In fact, the report notes, studies of death certificates show no widespread problem.

"They're not finding evidence of environmental (health) hazards in ore dust," Sundberg said. "You can't scientifically prove a negative. You can never say never. But it appears the exposure to taconite isn't the cause" of lung problems on the Iron Range.

Frank Ongaro Jr., president of the Iron Mining Association of Minnesota and a member of the study's citizen's advisory panel, declined to comment on report specifics until the panel can see it first. Panel members included community members, public health officials, state agencies, congressional representatives, steelworkers, retirees and the taconite industry.

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