I just found this thought-provoking article
A lot of people may not know it but our leafy green friends do a lot more work than we think! Trees and plants work hard to clean the air that we breathe.
Clean air is a top priority for many people but we produce more pollution and cut down more trees. How soon will it be before the air we breathe becomes to toxic?
Plants require carbon dioxide to grow which happens to be a by-product oxygen breathing animals produce. Plants clean our air by taking the carbon dioxide and converting it to oxygen. In turn we are helping each other.
Have you even had the chance to breathe fresh mountain air? The air is crisp and fresh. It gives off a sense of being clean.
Plants also help control the humidity and absorb toxins or off-gassed chemicals. Just a few more ways that plants help clean the air!
And here are some plants which purify the air: http://www.sustainablebabysteps.com/types-of-houseplants.html