What would you do if you found out that the roads you drive on could cause cancer?

This is the reality that residents face in Dunn County, North Dakota. For roughly 30 years, gravel containing the potentially carcinogenic mineral erionite was spread on nearly 500 kilometers of roads, playgrounds, parking lots, and even flower beds throughout Dunn County.

Concerns about erionite were first unveiled in Central Anatolia, Turkey, where an epidemic of mesothelioma - a normally rare cancer of the smooth lining of the chest, lungs, heart and abdomen - was responsible for up to 50 percent of the deaths in some villages. Although it is found in 12 states, erionite remains an unregulated mineral in the U.S. because it has not been used commercially and was previously thought that, unlike asbestos, human exposure was extremely limited. However, new evidence of its prevalence and dangers is coming to light, and scientists are beginning to wonder whether we should be worried.