In the 1980s NASA joined forces with the Associated Contractors of America (ALCA), to determine the most effective indoor plants for removing toxic agents from the air.
The study, led by Dr. B. C. Wolverton, found that some plants were effective at filtering out the likes of benzene, ammonia and formaldehyde from the air, helping to neutralise the effects of sick building syndrome.
The Chrysanthemum morifolium or Florist’s Chrysanthemum:
alongside Spathiphyllum or Peace Lily:
proved most effective, both shown to filter out amounts of benzene, formaldehyde, trichloroethylene, xylene, toluene and ammonia.
(This Wikipedia page lists which are toxic to cats and dogs)
Source: NASA Guide to Air-Filtering Houseplants | LoveTheGarden.com By Connor Macdonald