A study by researchers at UNLV found asbestos in the air in Boulder City and southern Clark County, Nevada. Professor Brenda Buck, a geologist with the University of Nevada at Las Vegas, was in the middle of a different study when she found naturally occurring asbestos outside Boulder City.

The asbestos found is the same as that previously mined in Libby, Montana. It is the most lethal form of asbestos known.

Other universities are now joined in to find out how dangerous it is and to study possible cancers associated with it.

"What we have identified is a hazard and people should have the opportunity to know about it so they can make choices, said Buck.