No one plant can reduce all contaminants, however, so a variety of plants is required to remove a range of chemicals. It is suggested that one or two plants per 10 square metres is usually sufficient to reduce indoor pollution.
Formaldehyde
Sources: foam insulation, plywood, clothes, carpeting, furniture, paper goods, household cleaners.
Suitable plants:
philodendron
spider plant
golden pothos
chrysanthemum
Sansvieria (snake plant).
Benzene
Sources: tobacco smoke, petrol, synthetic fibres, plastics, inks, oils, detergents, rubber.
Suitable plants:
Hedera helix (English ivy) (How to propagate ivy)
Dracaena marginata
chrysanthemum
gerbera (How to grow gerberas indoors)
Spathyphyllum (peace lily).
Trichloroethylene
Sources: dry cleaning, inks, paints, varnishes, lacquers, adhesives.
Suitable plants: gerbera, chrysanthemum, Spathyphyllum (peace lily), Dracaena marginata.
http://home.vicnet.net.au/~mecfs/general/plants.html
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