07 MAR 2022

Do houseplants absorb car fumes?

Boffins at the University of Birmingham have made the welcome discovery that common houseplants suck up nitrogen dioxide (NO2) produced by traffic outside, thereby reducing air pollution in homes and offices. According to the Daily Telegraph, the researchers set up a test chamber containing levels of nitrogen dioxide equivalent to those in a building next to a busy road and placed either a peace lily, corn plant or fern arum inside. In a one-hour test, the team established that the plants could remove about 50% of the pollutant in the chamber. From this they extrapolated that five plants could reduce the pollutant in a poorly ventilated office by 20%.

Nitrogen dioxide is produced when fuel is burned and is found in emissions from vehicles and power plants. It can damage our respiratory systems making people more susceptible to lung and heart disease, asthma and infections. Lead researcher, Dr Christian Pfrang said, “The plants we chose were all very different from each other, yet they all showed strikingly similar abilities to remove NO2 from the atmosphere. The more plants, the more removal. This is very different from the way indoor plants take up CO2 in our earlier work, which is strongly dependent on environmental factors such as night-time or daytime or soil water content.”

The researchers are still in the dark, however, about how exactly the plants process the NO2. They found no trace of the plants releasing the NO2 back into the atmosphere, suspecting instead that a biological process is taking place involving the soil that the plant grows in. The research, which was carried out in partnership with the Royal Horticultural Society (RHS), was published in Air Quality, Atmosphere and Health.

Regular readers of this blog will know that we at For Peat’s Sake are big believers in the power of houseplants. Discovering that they remove noxious NO2 from homes and offices is yet more confirmation of the benefits they bring to those who invest in them. And if you want to treat your hard-working houseplants to the best growing medium, plant them in our professional-grade coir. Not only is it light and clean, it helps protect the planet by providing an alternative to peat compost which releases CO2 into the atmosphere when it is dug out of bogs. Here’s to cleaner air both in our homes and outside!