U of M study confirms mesothelioma, Iron Range taconite industry linkIt long has been suspected, and now it’s confirmed: There’s a link between working in the taconite industry and unusually high rates of a rare lung disease on the Iron Range.
By: John Lundy, Duluth News Tribune
It long has been suspected, and now it’s confirmed: There’s a link between working in the taconite industry and unusually high rates of a rare lung disease on the Iron Range.
But University of Minnesota researchers, who have been on the case since 2008, haven’t found the smoking gun that explains the link.
They’ve also concluded that exposure to dust from today’s taconite operations is “generally within safe exposure limits.”
Researchers from the university’s School of Public Health released the latest results of the Taconite Workers Health Study, which will end later this year.
The $4.9 million study, commissioned by the Minnesota Legislature in 2008, sought to explain the unusual number of cases of mesothelioma among men who worked or had worked in the taconite industry.
Mesothelioma is a rare, fatal form of cancer almost exclusively seen in people who have been exposed to asbestos, according to the Minnesota Department of Health.
At least 82 Iron Range residents have died in recent years from mesothelioma, which often doesn’t appear until 30 to 40 years after initial exposure to asbestos.
Previously, the research team confirmed the rate of mesothelioma on the Iron Range is almost three times higher than that of the general population in Minnesota.
What’s new on Friday is the definite link to the taconite industry. Every year a worker spent in the industry increased the risk of mesothelioma by 3 percent, the researchers reported in a School of Public Health news release.
But the “why” remains a mystery.
Researchers found little trace of traditional asbestos-size mineral fibers in their study. They’ve focused instead on shorter fibers called “elongated mineral particles” or EMPs. On Friday, they said they did find a “potential link” between cumulative exposure to workplace EMPs and mesothelioma in taconite works.
“However, the link is not felt to be certain,” the news release said.
That means they can’t say for sure that the dust from taconite operations causes mesothelioma. Dr. Jeff Mandel, the study’s principal investigator, said researchers also still are looking for other possible sources of asbestos outside of the iron ore industry that may have affected the workers.
Taconite workers also have higher-than-expected risks of all types of cancer and heart disease, the news release said. That leads researchers to believe other factors, including lifestyles, may be at work, it said.
Even with an increased risk, mesothelioma is still a rare disease, and the chances of contracting it are slim, the news release noted.
The researchers also had good news for the Iron Range:
r Air quality in communities surrounding the mines is better than in most parts of Minnesota in terms of particulates in the air.
r Exposure to dust from taconite operations is, in general, within safe limits.
r Spouses of taconite industry workers are at no greater risk of contracting dust-related lung diseases than the general public in Minnesota.
“We’re hopeful that the results to date will allay fears that taconite dust has generated broad harm to the general public,” Mandel said in the news release.
The University of Minnesota Medical School and the Natural Resources Research Institute at the University of Minnesota Duluth also participated in the study.