The dust clouds that emanate from trucks and busses in rural North Dakota may not seem harmful, but a recent study published in the July issue of Proceedings of the National Academy of Sciences (PNAS) suggests that these clouds may have high levels of erionite, a mineral that can cause mesothelioma, a form of lung cancer linked to continued asbestos exposure.
Essentially, researchers had previously linked erionite exposure to Turkish villages where residents had high rates of mesothelioma. They recently studied gravel roads in North Dakota, where rocks containing erionite had been used to pave more than 300 miles of roads over the last 30 years. The researchers compared samples from North Dakota to those from the Turkish villages and found a number of similarities; specifically the chemical concentration that would likely cause mesothelioma.
As such, the scientists expressed a concern for the increased risk of future cases coming from North Dakota. They based their theory on the extended latency period (i.e. 30-60 years of exposure to develop mesothelioma), and the fact that erionite deposits have only been mined within the last 30 years. They also indicated that other western states, including California, Oregon and Arizona have erionite deposits.
The concern is complicated by the fact that no safety benchmarks have been established for erionite exposure in the U.S. Nevertheless, the scientists advocated for future studies to analyze such levels in other areas of the country, as well as materials that may contain erionite, so that prevention and screening mechanisms may be established.
Source: ScienceDaily.com, Cancer-Causing Mineral Found in U.S. Road Gravel: Erionite in Roads May Increase Risk of Mesothelioma, July 11, 2011