Potted plants do not improve indoor air quality: a review and analysis of reported VOC removal efficiencies

Posted by Siru Heiskanen on Dec 4, 2019

Authors: Bryan E. Cummings & Michael S. Waring

Year of publication: 2019

Publication: Journal of Exposure Science & Environmental Epidemiology (2019) doi:10.1038/s41370-019-0175-9

Keywords: VOCs, plants, indoor air, biofiltrering,

Link to publication

Indoor air pollution largely consists of VOCs from the indoor environment itself, such as building materials, paints, adhesives, consumer products, air fresheners among others. VOCs are known to have many negative and even serious effects on the health and well-being of people, and though mechanical air ventilation is commonly used in buildings to reduce the chemical load, it has many drawbacks, such as increase in outdoor sourced pollutants (ozone, PM) and high energy consumption. For this reason, alternative and supportive methods to reduce VOC loads from indoor air are being researched.

Experiments have shown that plants reduce VOC concentrations in air, and therefore improve indoor air quality. However, the results are often reported in ways that are not applicable to real indoor environments. In this article, 196 experimental results were standardized and analyzed to assess the the effectiveness of potted plants to remove VOCs.

The study found, that:

  • It would take up to a 1000 potted plants/m2 for combined VOC-removing ability to achieve the same removal rate as ventilation systems already do
The study concludes, that future efforts should be shifted from potted plants' (in)abilities to passively clean indoor air to active biofiltration technologies, such as biowalls which mechanically pull air through the substrate the plants live in.