The final report on a School of Public Health study investigating the health of Minnesota’s taconite industry workers shows an association between mining dust exposure and cases of a rare cancer, and in response, urges increased body monitoring and disease prevention initiatives for employees.
“Mining is of great importance to the people of Minnesota and to our State’s economy,” said Finnegan. “The State invested significant funds and time into the Taconite Workers Health Study and we felt it was important to indicate follow-up activities in order to continue to improve the health and safety of all miners moving forward.”
The study was launched in 2008 at the request of the State Legislature after the Department of Health detected an unusually high number of cases of mesothelioma, a rare cancer of the lung lining, in Minnesota taconite workers.
To address the concern, the study examined three questions to assess the occupational health risks to taconite workers and search for a link to the mesothelioma cases:
Is working in the taconite industry associated with mesothelioma and/or with other respiratory or non-respiratory diseases?
The study found taconite workers had higher than expected death rates from three diseases when compared to the general Minnesota population: mesothelioma, lung cancer and heart disease. In instances of lung cancer and heart disease, working in the mining industry was not believed to be the prominent cause of the illnesses.
What factors, particularly dust from taconite operations, are associated with mesothelioma and other respiratory diseases?
Researchers found that the length of time people worked in the industry was specifically linked to higher levels of mesothelioma. Pinpointing it more, exposure to a fiber-like mineral–referred to as elongate mineral particle (EMP)–was linked to mesothelioma.
The investigators determined EMP exposure could be from either dust generated in mining and processing, or from its most widely known source, commercial asbestos exposure.
As a result, workers with above-average exposure to dust containing EMPs were twice as likely to develop mesothelioma as workers with below-average exposures.
Are workers at risk for common dust-related lung diseases and are their spouses at risk for the same diseases due to their partners working in the industry?
A health screening–including x-rays–of current and former taconite workers and their spouses was conducted in 2010-11.
The results revealed x-ray evidence of dust-related scarring of the lung and lung lining (pleura) in workers. Once again, there was evidence of a link between EMP exposure in workers and their observed scarring of the lung pleura.
Spouses of taconite workers, however, showed lower instances of lung scarring comparable to what’s been reported for the broader general public.