Most of us know that air pollution caused by traffic is bad for our health. But the reality is that indoor air pollution can be just as bad – both at work and in our own homes. It’s been linked to a range of health problems, like asthma, wheezing, conjunctivitis and eczema.
Studies show that plants really can improve our wellbeing, leading to a boost in mood, memory and productivity.
The most concerning air pollutants that researchers have looked at are volatile organic compounds, or VOCs, which can be found in fire retardants, aerosol sprays and cleaning products. One such compound is limonene, which we might know by its delicious citrus scent. Unfortunately, it reacts with the ozone in the air to form the potentially dangerous chemical formaldehyde!
Another chemical where high levels can cause problems is carbon dioxide, resulting in poor concentration and decision making. Ventilating areas well can help with both these things, but where that’s not possible, houseplants are a surprisingly good and natural way to purify the air.
A green solution?
The suggestion that house plants could help with air quality came from an unlikely source. In 1989, the space agency NASA showed that houseplants could significantly lower levels of VOCs and CO2 in the air in a sealed chamber. What was lacking, was the proof they could work in our own homes or offices. It did encourage a wave of research into plants’ potential to absorb chemicals, and since then, research has taken off looking at their impact in different – more realistic – living environments. One study, for example, suggested that introducing potted plants to 60 offices with high levels of volatile organic compounds reduced levels of these compounds by between 50 and 75%.
One study in Norway assessed the impact of introducing plants to an office or school and the radiology department of a hospital and found that filling the office with houseplants led to fewer coughs, headaches and fatigue.
Less stress and better productivity
In addition to making you feel physically better, there have been claims that having indoor plants can be good for your mind too. If you’re already a plant lover, you may notice yourself feeling more comfortable, breathing in more deeply and feeling the benefits of the calming effect of nature - and there has been research which s this. Studies show that plants really can improve our wellbeing, leading to a boost in mood, memory and productivity. One even found that when employees were able to view plants from their desk, they performed better in a specific test of concentration by 19%.
How do they help?
Dr Tijana Blanusa from the Royal Horticultural Society has been studying the ways plants improve air quality. She explains that there are several ways plants can work to remove compounds from the air. On the underside of the leaf, there are pores called stomata that let the air in, and water vapour out. A lot of gaseous compounds are removed though this pathway, while at the same time, water vapour causes our air to become more humid. Another way is through the soil, where microorganisms break down the compounds.
