List of air-filtering plantsThe first list of air-filtering plants was compiled by NASA as part of the NASA Clean Air Study, which researched ways to clean air in space stations. As well as absorbing carbon dioxide and releasing oxygen, as all plants do, these plants also eliminate significant amounts of benzene, formaldehyde and/or trichloroethylene. The second and third list are from Dr. B.C. Wolverton's book and paperand focus on removal of specific chemicals....
http://en.wikipedia.org/wiki/List_of_air-filtering_plants