Dr. Brenda Buck examines rocks for naturally occurring asbestos
Image Source: Dr. Buck & colleague examine rocks for NOA

The recent discovery of windblown asbestos dust near Las Vegas, NV has drawn new attention to the phenomenon of naturally occurring asbestos (NOA). Dr. Brenda Buck, a UNLV geologist, was testing for arsenic and other toxic chemicals when she unexpectedly found a different, but equally dangerous, substance: actinolite, one of six minerals categorized as asbestos. She and her colleagues published a paper last year detailing their findings, which focused on the area around Boulder City, a small town 20 miles southeast of Las Vegas.

Asbestos is produced naturally through geological processes and is usually buried harmlessly in the earth. Most human exposure occurs when the carcinogenic fibers are extracted and used for industrial purposes; a great deal of progress has been made in educating people on how to limit their exposure in their homes and workplaces.

However, Dr. Buck’s discovery, along with locations such as the Superfund site of Libby, Montana, casts a harsh light on the ways in which people can unwittingly come into contact with the substance in the natural world. Dr. Buck’s paper concluded that the Boulder City–area asbestos is “highly respirable and possibly carcinogenic,” and suggested that further study is imperative to assess the risk to the public’s health.

Dr. Buck is continuing to study the extent of the NOA in southern Nevada. She considers the work so hazardous that no graduate students are assisting her. In the meantime, the EPA is still evaluating how to manage the substance in areas where it occurs naturally.

Protect Yourself

Naturally occurring asbestos can be frightening, but a little care can go a long way toward minimizing the dangers.

Wherever possible, you should simply avoid areas where NOA is known to be present, but of course that won’t always be an option. If you live in an area where naturally occurring asbestos is unavoidable, you can take steps to minimize your exposure.


  • Stick to paved trails when you hike, run or bike.

  • Avoid going outside on days that are excessively windy or dusty.

  • Travel slow and keep your windows up when driving on unpaved roads.

  • Cover areas of NOA on your property. Suitable coverings can include paving, asbestos-free soil, sod, plants, or simply a tarp.

  • When gardening, first water the area where you intend to dig.

In The Home

  • In the event of wind, nearby construction or something else that might send dust into the air, keep your home’s doors and windows shut.

  • Brush off pets before bringing them into the house in case asbestos dust is present on their fur or feet.

  • Wipe feet on a doormat before going inside, and have people remove their shoes before going in the house.

  • Simply bathing and doing laundry (washing contaminated clothes separately) when you think you may have been exposed can help as well.

The fact that the fibers are invisible to the naked eye, and that health effects often don’t manifest for decades, make asbestos especially frightening. The idea that the substance could occur naturally near your home is an unpleasant thought. But if you live in an area with NOA, you can take comfort in the knowledge that a little care goes a long way toward minimizing the dangers.