Dec. 4, 2009 — Certain plants can remove dangerous airborne contaminantscommonly found in homes, new research suggests.
The contaminants plants can remove from the air include harmful volatileorganic compounds such as benzene, toluene, octane, alpha-pinene, andtrichloroethylene (TCE), the researchers say in a study published in the Augustissue of HortScience.
Of 28 indoor plants tested, Stanley Kays, PhD, of the University of Georgiaand his horticultural team identified five “super ornamentals” that had thehighest rates of contaminant removal, a process called phytoremediation.
These are the red ivy (Hemigraphis alternata), English ivy (Hederahelix), variegated wax plant (Hoya cornosa), asparagus fern(Asparagus densiflorus), and the purple heart (Tradescantiapallida), the study says.
The scientists placed the plants in glass, gas-tight containers, exposingthem to common volatile organic compounds found indoors. And the plants did agood job of removing the airborne contaminants.
Researchers say there may be thousands of plants capable of removingairborne contaminants.
Volatile organic compounds are likely wafting about in every house, Kaystells WebMD. They’re given off by home furnishings, carpets, plastics, cleaningproducts, building materials such as drywall, paint, solvents, adhesives, andeven tap water, Kays says.
The pollutants have been linked to many illnesses, including asthma, cancer,and reproductive and neurological disorders, and claim 1.6 million lives ayear, he says, attributing that number to the World Health Organization.
Air inside homes and offices is often a concentrated source of suchpollutants, in some cases up to 100 times more polluted than outdoor air, Kaystells WebMD.
No one yet knows why some plants are effective at remediation, but he andother scientists are digging for answers.
“We also want to determine the species and number of plants needed in ahouse or office to neutralize problem contaminants,” he says in a news release.“The idea that plants take up volatile compounds isn’t as much of a surprise asthe poor air quality we measured inside some of the homes we tested.”
There is no affordable way for average consumers to determine the airquality of their homes, Kays says.
He tells WebMD that not all volatile organic compounds are toxic, and thatsome plants emit toxins, too. But placing some common ornamentals indoors hasthe potential to improve air quality, he says.
“In reality, you are much more in danger from these compounds inside thanoutside,” he tells WebMD. “All houses have these compounds. Even computers givethem off. It would be advantageous then to have a few plants in your house.They also keep humidity at fairly constant levels.”
But there is no magic list on the horizon, he says.
“You might have some plants that are good with benzenes but not withformaldehyde, which comes from upholstery, carpet, a lot of sources,” he tellsWebMD.
Hopefully, he says, in a few years there will be an affordable test that canalert people to the contaminants in their homes, and a list of the best plantsto help clean the air.
“Ideally, we’d have an extension service that would send out a packet thatwould do the test for you to send back and get recommendations,” he tellsWebMD.
He says scientists in Korea are “substantially ahead of us inphytoremediation research,” and one with whom he is collaborating, Kwang JinKim, PhD, of the National Horticultural Institute in Seoul, has evaluated theability of 86 species to remove indoor formaldehyde.