(转载时请注明出处：中草药文献检索与特性查询 http://www.natureleads.com)
家庭和办公室等室内空气污染在某些地区比室外空气污染严重得多。这些污染可来自油漆等五花八门的污染源，是影响人们健康的大问题。许多室内可挥发有机物已被显示与哮喘，癌症等多种急慢性疾病有关。据一份世界卫生组织2002年的报告，有害室内污染每年可能导致160万人死亡。
美国乔治亚大学园艺系Stanley J. Kays等人对观赏植物对室内可挥发有机物的清处作用做了研究。他认为，某些室内植物可以有效地清除有害的可挥发有机物，这不仅对身体健康有好处，也可使人精神健全。
Kays领导的研究小组研究了28种室内观赏植物清除有害可挥发有机物的作用。发现玉龙草（Hemigraphis alternata），常春藤（Hedera helix），球兰（Hoya carnosa）和武竹（Asparagus densiflorus）对所有被研究的可挥发有机物都有很强的清除作用。而紫万年青（Tradescantia pallida）对清除可挥发有机物中的四种有害化合物很好。
Plants Can Remove Harmful Indoor Airborne Contaminants, Study Says
Dec. 4, 2009 -- Certain plants can remove dangerous airborne contaminants commonly found in homes, new research suggests.
The contaminants plants can remove from the air include harmful volatile organic compounds such as benzene, toluene, octane, alpha-pinene, and trichloroethylene (TCE), the researchers say in a study published in the August issue of HortScience.
Of 28 indoor plants tested, Stanley Kays, PhD, of the University of Georgia and his horticultural team identified five “super ornamentals” that had the highest rates of contaminant removal, a process called phytoremediation.
These are the red ivy (Hemigraphis alternata), English ivy (Hedera helix), variegated wax plant (Hoya cornosa), asparagus fern (Asparagus densiflorus), and the purple heart (Tradescantia pallida), the study says.
The scientists placed the plants in glass, gas-tight containers, exposing them to common volatile organic compounds found indoors. And the plants did a good job of removing the airborne contaminants.
Researchers say there may be thousands of plants capable of removing airborne contaminants.
Volatile organic compounds are likely wafting about in every house, Kays tells WebMD. They’re given off by home furnishings, carpets, plastics, cleaning products, building materials such as drywall, paint, solvents, adhesives, and even 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 a year, he says, attributing that number to the World Health Organization.
Air inside homes and offices is often a concentrated source of such pollutants, in some cases up to 100 times more polluted than outdoor air, Kays tells WebMD.
No one yet knows why some plants are effective at remediation, but he and other scientists are digging for answers.
“We also want to determine the species and number of plants needed in a house 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 as the poor air quality we measured inside some of the homes we tested.”
There is no affordable way for average consumers to determine the air quality of their homes, Kays says.
He tells WebMD that not all volatile organic compounds are toxic, and that some plants emit toxins, too. But placing some common ornamentals indoors has the potential to improve air quality, he says.
“In reality, you are much more in danger from these compounds inside than outside,” he tells WebMD. “All houses have these compounds. Even computers give them 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 with formaldehyde, which comes from upholstery, carpet, a lot of sources,” he tells WebMD.
Hopefully, he says, in a few years there will be an affordable test that can alert people to the contaminants in their homes, and a list of the best plants to help clean the air.
“Ideally, we’d have an extension service that would send out a packet that would do the test for you to send back and get recommendations,” he tells WebMD.
He says scientists in Korea are “substantially ahead of us in phytoremediation research,” and one with whom he is collaborating, Kwang Jin Kim, PhD, of the National Horticultural Institute in Seoul, has evaluated the ability of 86 species to remove indoor formaldehyde.
