In a health study of Taconite Workers in Iron Range, Minnesota, the number of citizens who died of mesothelioma is higher than they reported a year ago up from 63 to 82. Researchers found the additional nine cases by checking death records of former residents who moved out of state.
The University of Minnesota is responsible for the study, which started in 2008 and will wrap up as early as mid-2012. So far, results indicate that the rate at which residents have contracted mesothelioma is much higher than it should be.
Mesothelioma is a rare and fatal cancer, caused primarily by exposure to asbestos fibers, which often takes 30 years or more after exposure to show up.
Exactly how Iron Range residents have been exposed to asbestos is a mystery. Speculation includes one theory that workers handled asbestos in certain products then carried it home. Another theory is that processing taconite rock (a low-concentrate iron ore that has been mined and processed in Minnesota since the 1950s) releases asbestos fibers from within the rock into the air. The mystery is what provoked the $4.9 million health study, which was approved by state lawmakers in 2008.
Researchers have collected data on people who worked in mining as far back as the 1920s. So far, the study shows that out of about 46,000 taconite workers who ever worked in the industry, 1,681 developed some sort of lung cancer.
Currently, the results from more than 2,000 air samples taken over the last two years at Minnesotas six operating taconite plants show safe dust levels. Asbestos levels are extremely low, according to the study. Silica concentration was found to be higher than acceptable in some cases.