Back in late 1989, US National Aeronautics and Space Administration (NASA) released a report on "Interior Landscape Plants for Indoor Air Pollution Abatement" with the Associated Landscape Contractors of America (ALCA) to address the "Sick Building Syndrome". Volatile organic compounds (VOC) like benzene, formaldehyde, and trichloroethylene, xylene, toluene and ammonia present in adhesives, upholstery, carpeting, copy machines, manufactured wood products, pesticides, cleaning agents, synthetic fragrances etc build up in stagnant indoor environment. As a result negative health effects like headaches, dizziness and eye irritation increases sickness absenteeism and decreases productivity of the workers.
In the study led by Dr. B. C. Wolverton, it was found that some plants were effective at helping to neutralise and filter the effects of sick building syndrome by filtering out the chemicals. It is most effective if we have at least one plant per 100 square feet (10 square metre) of enclosed environment. Here is the list of plants identified from the study: