A “naturally occurring mineral” that you might not even know exists could be a potential hazard, especially if you live in the West.
NIOSH recently released a post on their science blog entitled “Erionite: An Emerging North American Hazard” comparing Erionite to asbestos with regards to the nature of the mineral and the similar health hazards that it poses. A natural fiber that is the result of volcanic ash that has been broken down over time by ground water and the weather, the mineral can become airborne and be inhaled. The body reacts to it in much the same way as it does asbestos.
First diagnosed in 1981 in a road worker who worked outdoors in an area rich in Erionite, the mineral has slowly grown in awareness.
You can read the complete blog post on the CDC/NIOSH blog.
Check out the map to find the highest Erionite occurrences.