Surprising source of indoor air pollution: House plants

(Photo: Potrokhova Kateryna
& Dmitry Lar)

Previous research has demonstrated that common house plants can remove harmful indoor air pollution, classified as volatile organic compounds or VOCs. But new research shows that some house plants can actually produce VOCs, contributing to indoor air pollution.

Scientists at Georgia's Department of Horticulture published a paper on the subject in the journal HortScience. Their experiment: Feed four types of house plant filtered air and measure what gases become present in enclosed glass containers.

The peace lily produced the most VOCs: 23. The areca palm produced 16, the weeping fig 13 and the snake plant 12.

So what gives?

Researchers concluded that some of the VOCs were released by microorganisms in the soil (some of microorganisms in soil are credited with removing VOCs in other experiments). But many of the VOCs came from pesticides applied to the plants at the greenhouses or farms where they were grown, and 11 were produced by the plants' plastic pots. Whatever the source, the plants produced more VOCs in daytime sunlight than at night.

The scientists noted that they did not determine whether the levels of VOCs produced might be harmful to human health. A cursory glance at the results suggests that, to reduce indoor air pollution, one should choose organic house plants grown without pesticides and pot them in ceramic or other non-plastic pots.

More from The Daily Green

• The Dirty Dozen: 12 Foods to Eat Organic
• The Clean 15: Foods With Low Pesticide Residue
• Organic Foods and Beyond: 18 Ways to Green Your Diet
• How to Purify Your Indoor Air: 25 Tips
• How to Start Your Own Organic Garden

Reprinted with permission of Hearst Communications, Inc