1. Bamboo Palm or Reed Palm (Chamaedorea sefritzii) - Bamboo Palm acts as a natural humidifier and removes the harmful chemicals formaldehyde, xylene and toluene from air.
2. Snake Plant or Mother-in-law's Tongue (Sansevieria trifasciata 'Laurentii') - A study conducted by NASA found that Snake Plant is one of the best plants for improving indoor air quality, as it passively absorbs toxins like nitrogen oxides and formaldehyde. Because of this quality, it is also known as 'The Bedroom Plant'. Note that it is known to be toxic to cats and dogs.
3. Areca Palm (Chrysalidocarpus lutescens) - Areca Palm filters indoor air of xylene and toluene chemicals. Wolverton also specified that this plant is an effective humidifier, and is also known as 'The Living Room Plant'.
4. Spider Plant (Chlorophytum comosum) - Spider Plants also reduce indoor air pollution in the form of formaldehyde, xylene and toluene.
5. Peace Lily (Spathiphyllum 'Mauna Loa') - Peace Lily is a clean-all house plant, purifying air from benzene, formaldehyde, trichloroethylene, xylene , toluene and also ammonia. Note that Peace Lily is also known to be toxic to cats and dogs.
6. Gerbera Daisy or Barberton Daisy (Gerbera jamesonii) - The respiratory cycles of most plants decrease in the evening hours and they start absorbing oxygen, releasing carbon dioxide. But Gerbera Daisies continue releasing oxygen throughout the night, which helps you breath and sleep better. These colorful plants also remove benzene, formaldehyde and trichloroethylene from air.