Asbestos is the name given to a group of fibrous minerals that occur naturally in the environment.
Because of its fiber strength and heat resistance asbestos has been used in a variety of building construction materials for insulation and as a fire retardant. Asbestos has also been used in a wide range of manufactured goods, mostly in building materials (roofing shingles, ceiling and floor tiles, paper products, and asbestos cement products), friction products (automobile clutch, brake, and transmission parts), heat-resistant fabrics, packaging, gaskets, and coatings.
Naturally occurring asbestos refers to those fibrous minerals that are found in the rocks or asbestos in soil, which is released into the air by routine human activities or weathering processes.
If a building is constructed prior to 1990 there is a possibility that asbestos containing materials are found within the soil, produced as a result of bad construction , demolition or landscaping practices.
Human Health Risk from Asbestos in Soil
Asbestos in soil only poses a risk to human health when elevated levels of asbestos fibres are breathed in. The risk of asbestos in soil is dependent on the use, quantity and nature of the asbestos material which has contaminated the soil. Bonded asbestos forms the lowest risk as the asbestos fibers are bonded requiring much force to liberate the fibers in the air. Friable asbestos poses a greater risk because they are easily disturbed or broken.
When breathed in, asbestos may cause lung cancer, mesothelioma, which is a rare form of cancer that is found in the thin lining of the lung, chest and abdomen, and heart, and asbestosis, which is a serious progressive, long-term, non-cancerous disease of the lungs.
Who is at risk for asbestos exposure?
Almost everyone has been exposed to asbestos at some time in their life. Higher levels of asbestos are more common near:
- An asbestos mine or factory
- A building being torn down or renovated that contains asbestos products.
- A waste site where asbestos is not properly covered up or stored to protect it from wind erosion. An area containing naturally occurring asbestos that has been disturbed through activities that crush asbestos containing rock or stir up dust in soils that contain asbestos fibers.
The Environmental Protection Agency (EPA) has several approaches in mitigating exposures to asbestos in soil or other forms naturally occurring asbestos. Some of those approaches are as follows:
- Leave NOA material in place and undisturbed
- Cover or cap NOA material
- Limit dust generating activities
- Accessibility of NOA (ground surface vs. below ground surface)
- Types of activities that disturb NOA (construction project vs. gardening)
Read more about these ways to minimize exposure, as well as examples of engineering and work practice to reduce exposure when working with asbestos in soil on the EPA website.
Managing Asbestos in Soil
Identifying the type and nature of asbestos in the soil is critical to assessing the risk and forming appropriate control measurements and management plans. Asbestos soil testing can confirm the presence of asbestos, however, the sampling technique is critical as asbestos in soil is not homogenous.
According to the Toxic Substances and Disease Registry, asbestos air monitoring is generally recommended to quantify any perceived risk when moving asbestos in soil, particularly during construction and earth moving work.