Asbestos isn't the only material that causes malignant mesothelioma (a kind of lung cancer). A naturally-occurring substance called erionite also is a culprit, and the evidence so far suggests it is much more toxic. The hazard has been recognized by some experts for many years, and has been addressed in a spotty manner. But risky situations have still been created, and concern is rising as development that disturbs erionite deposits occurs in 12 western states.
There are more than 50 known deposits, and most are in NV, CA, OR, AZ, and WY. Other states with deposits include NM, CO, UT, ID, ND, MT, and SD. The sites can be disturbed by construction and operation of roads, pipelines, power lines, wind farms, solar farms, recreation sites, and other land uses.
- "Occurrences of Erionite in Sedimentary Rocks of the Western United States,"  US Geological Survey, 1996, by Richard Sheppard (includes a little detail about each location).
Erionite has also been found in many other countries, including Austria, Canada, the CzechRepublic, the Faroe Islands, France, Germany, Iceland, Italy, Japan, Kenya, Mexico, New Zealand, Russia, Scotland, Tanzania, and Turkey. There also is some evidence of its presence in the state of Washington, according to:
- "Re-evaluation and Re-classification of Erionite Series Minerals,"  Environmental Geochemistry and Health, March 20, 2008, by A. Umran Dogan and Meral Dogan (doi:10.1007/s10653-008-9163-z).
For many other sources of information on erionite, see:
In order to better understand and deal with this threat, which isn't targeted by any US federal regulations, numerous federal agencies held a workshop Oct. 12, 2011. The speakers at the workshop are likely good sources for your coverage.
- "Upcoming NIEHS Workshop on Erionite and Mesothelioma,"  National Institute of Environmental Health Sciences newsletter (The Environmental Factor), October 2011, by Melissa Kerr.
Some of the threatening situations that have occurred with disturbance and use of erionite deposits are discussed in this media article:
- "Peril in the West: After Three Decades, Officials Ponder Action on Cancer-Causing Erionite,"  FairWarning, Oct. 7, 2011, by Myron Levin.