Want to improve the indoor air quality in your home or office? Get a houseplant.
Plants can absorb air pollutants and can alleviate some "sick building syndrome" symptoms such as headaches and eye, nose or throat irritation which may be caused by inadequate ventilation, chemical contaminants (ie. VOCs, carbon monoxide) or biological contaminants (ie. mold, pollen).
You don't have to overdo it. One plant for every 10 sq yards of floor space should be plenty.