Plants are capable of immediately cheering up any environment, they are a joy for the eyes and a fantastic pastime, but they are also much more. In fact, plants are able to improve the air in closed environments by removing irritants and toxic substances, such as nitrogen dioxide, or NO2, a pollutant released by the exhaust gases of cars, especially if with diesel engines. This is what emerges from a very recent scientific research published in the journal Air Quality, Atmosphere & Health volume by a team from the University of Birmingham (Gubb et al, Air Quality, Atmosphere & Health, 2022).
What is nitrogen dioxide and what damage it causes to health
Nitrogen dioxide is a substance released mainly from the exhaust gases of cars. Exposure to nitrogen dioxide is associated with respiratory diseases, a decrease in lung function and inflammation of the airways. So how to get rid of this substance? Certainly a good air exchange is essential, provided however that this does not occur during the hours with greater traffic. There are also natural remedies that, in addition to making the environment more colorful and cheerful, also help to clean the air from many sources of pollution, the plants. Studies conducted by NASA as early as the 1980s had shown that some plants are able to remove carcinogenic substances such as formaldehyde, benzene and toluene from indoor air. But can plants help with nitrogen dioxide?
Plants that remove nitrogen dioxide from the air
To answer this question, scientists at the University of Birmingham have developed the study we are talking about today. The researchers selected three types of plants that can commonly be found in homes or offices. The plants used in the experiment are, in particular, Peace lily (Spathiphyllum wallisii), Corn plant (Dracaena fragrans) and fern arum (Zamioculcas zamiifolia). Each plant was placed in a test room measuring 0.15 cubic meters in size, with an amount of NO2 similar to that found in an office next to a busy road. After an hour, each plant was able to remove half of the NO2 in the air. The researchers also estimated that this result obtained in the small test room corresponds to the ability of 5 plants to remove about 20% of NO2 from an office of about 15 cubic meters, with poor ventilation and with high NO2 values. Also noteworthy is the fact that the ability of plants to remove NO2 from the atmosphere does not depend, as is the case with carbon dioxide, on the light conditions of the environment or soil. The plants have proved equally capable of absorbing NO2 both in conditions of high brightness and in darkness, both with wet and dry soil. Not only that, NO2 absorbed by the plant is then not released into the atmosphere at a later time. The processes that lead to the absorption of NO2 by the plant are not yet known, but it is believed that the soil where the plant grows is also involved.
Here is further proof that nature can help to cope with the most disparate problems. Today we know that plants not only make environments more hospitable but also healthier, helping to remove nitrogen dioxide from the air, at least in part and depending on the number of plants used, thus also protecting the health of our airways.