Researchers from Syracuse University, USA (2011), developed a dynamic botanical air filtration system (DBAF). This consisted of a hydroculture based potted plant unit, with fan-assisted airflow through a growth media mixture of activated carbon and porous shale pebbles. The plants used were Golden Pothos (Epipremnum aureum).

Initial short-term performance testing used a full-scale test chamber.  Longer term testing involved the integration of the DBAF within the HVAC of a new office space (96.8 m^>2) and evaluated the effects of moisture content on removal efficiency.

The researchers found that the (DBAF) botanical filter:

• Performed consistently over the 300 day test period
• Increased winter relative humidity by 20% and summer by 15%
• Gave single pass removal efficiencies of 70% formaldehyde and 40% toluene
• With most effective removal occurring at between 5-35% media bed content

Finally, it was determined that when used in conjunction with a HVAC system, the botanical filter combined with only 5% outdoor air, was the equivalent of using 25% unfiltered outdoor air. Calculations suggest that using the DBAF system could reduce energy cost by between 10-15%