HONOLULU, July 25 (UPI) -- A mineral with similarities to asbestos, found in gravel of roads in some U.S. states, presents a risk for mesothelioma, a type of cancer, researchers say.
Clouds of dust with high levels of the mineral erionite stirred up by passing traffic can cause fibers of the material to lodge in people's lungs, increasing the risk of the cancer that strikes the membranes around the lungs, a release from the University of Hawaii Cancer Center reported Monday.
Dr. Michele Carbone, the center's director, has previously linked erionite exposure in some Turkish villages to unusually high rates of mesothelioma, the release said.
He and his colleagues have now turned their attention to potential erionite exposure in the United States where at least 12 states have known erionite-containing rock deposits.
They focused their efforts on Dunn County, N.D., where rocks containing erionite have been used to produce gravel for the past 30 years.
Airborne levels of erionite in North Dakota were comparable to levels found in Turkish villages with 6-8 percent mortality rates from mesothelioma, they found.
"Based on the similarity between the erionite from the two sources," Carbone said, "there is concern for increased risk of mesothelioma in North Dakota."
Because it can take 30 to 60 years of exposure to cause mesothelioma, and because many erionite deposits have only been mined for the past few decades, there is a possibility the number of cases could soon be increasing, the researchers said.