Perlite As a Contaminant


Perlite is a growing medium that is well known for its ability to retain both water and nutrients. It is a form of natural glass that comes from the high temperatures and pressure of volcanic magma. It is mined all over the world and is most commonly used in construction or industrial projects rather than horticulture.


Perlite is a volcanic rock that has been heated and formed into glass. Perlite is then crushed to be used in construction, industry or horticulture as a growing medium. Crushed pieces, before being sold to the consumer market, are typically heated to temperatures of 2000 degrees, evaporating moisture within the rock and causing expansion. Perlite is very popular for its ability to retain water and can be used in hydroponics.


Perlite can be used either on its own in hydroponics or mixed into the soil to improve water and nutrient retention for the plant. This ability allows for a reduction in fertilization and watering for the plant and allows air to move freely around the roots. Gardeners should look into the risks of using perlite before switching from traditional soils to reduce the chance of contamination.

Contamination in the Soil

Perlite retains large quantities of nutrients and minerals that can build up and cause runoff into nearby landscapes. This will contaminate such habitats over long periods of time if the local landscape is unable to use these minerals. Measures must be taken to prevent and remove the risk of continued leached. These include minimizing the number of feedings and waterings of plants until absolutely necessary and keeping an eye on landscapes of close proximity to the perlite environment.

Perlite Contamination

Sterile perlite rocks that are sold to consumers have been treated to prevent decomposition of the rock over time. Rocks that are not treated are not meant for reuse and can potentially endanger the environment with hazardous bacteria and pathogens. These contaminations are typically the result of natural growing processes of nearby plants. The solution to this is having perlite retreated between plants to prevent buildup within the pores of the rock.

Health Risks

Perlite can cause damage to gardeners' lungs when excess dust from the treatment process is inhaled by the consumer. It is important to wear a mask when working with perlite and to wait for its dust to settle before each use. This will help prevent any health risks associated with perlite use in gardens.

Keywords: perlite growing medium, alternative gardening techniques, perlite contamination troubleshoot

About this Author

Jonathan Budzinski started his writing career in 2007. His work appears on websites such as eHow and WordGigs. Budzinski specializes in nonprofit topics, as he spent two years with Basic Rights Oregon and WomanSpace. He has received recognition as a Shining Star Talent Scholar in English while studying English at the University of Oregon.