Contact

Trees as filters to combat air pollution in cities

Research has found the effectiveness of plants to combat levels of air pollution in cities. The real question is: how effective are they?

This used to be a greener world

Scientists and environmentalists do not exaggerate when they say that plants are the Earth’s lungs. Without them, life on this planet would never have come to be. Photosynthesis is vital for its continuation, as it is the process by which the oxygen we breathe is created. Rapid deforestation in the name of industry will result in catastrophic consequences if we do not stop our blind economic growth. Of course, there are other sources that produce oxygen, such as algae, which are estimated to yield 30 to 50% of the world’s net oxygen, but the shrinkage of our forests and jungles will eventually result in a biological catastrophe.

This is one of the many reasons behind the protection of forested areas, as well as reforestation campaigns. A gradual change of mind that is also starting to consider the growth of greener areas in our towns and cities. This is, of course, good news. For the last fifteen or so years, architects and urban planners have started to think about green solutions for their proposals. Everything between the beauty of vertical gardens to the ambition of self-sustaining blocks that produce their own food, to more modest proposals such as Tredges, that is, trees that are used as hedges. Green spaces are here to stay.

Trees and plants serve functions other than being producers of oxygen. They can also work as filters to help combat the high levels of air pollution in our cities. This is something that has been found by Dr. Barbara Maher, who works at the University of Lancaster, in the UK, as an environmental researcher. Together with her team, she has designed a program to find which plant species of tredges could best be employed as a natural filter to mitigate the health impact of traffic-produced air pollution in primary schools.

Conducting an experiment

We have already talked about the effects of air pollution in the psychological development of both children and adolescents, and Dr. Maher’s research touches upon similar grounds. Since young people’s brains are still in development, she has stated, air pollution can be linked to delinquency and stunted brain development. Tredges, her research has found, work as effective, if somewhat limited, barriers against the dangerous concentrations of chemicals spewed by motor vehicles, such as PM 2,5 particulate matter.

The study was carried out in four primary schools in Manchester, one of them located right next to Princess Parkway, one of Europe’s busiest roads. Only mesh fencing or metal railing protect the schoolgrounds from the air polluted roads, and it was through the length of these lofty barriers where various types of trees were planted. To measure improvement in air quality, monitoring equipment was installed for the entirety of the test run. The results were mostly positive.

But not all plants are equal, which means that not all tredges will be as functional. Like all natural filters, they trap pollutants within their fibers, but the effectiveness of this depends on the peculiarities of each species, such as leaf density, porosity, shape, and area. Potted Western red cedar, for example, was part of the experiment, and the playgrounds of St. Ambrose Primary, one of the schools included in the program, saw a reduction of 30% in air contamination. On the other hand, Dr. Maher and her team placed silver birch trees at the border line between their campus in Lancaster and a busy road. They saw a reduction of more than 50% of fine particulate air pollution in the outside areas just behind the trees.

air pollution

A reason to be optimistic, but not very much

The numbers may look good, and they are, but we should not be carried away by them. Green solutions to clean up our polluted city air are always a welcome addition to the toolkit, but they can only take us so far. There is no softer way to say this: our air pollution problem is directly linked to economic and industrial activities, which are so massive they have defined an entire new unit of geologic time: the Anthropocene. Fine particulate matter in the PM 1, 2,5 and 10 ranges are produced by both motor vehicles and industrial processes, and no matter how thick tredges could ever be, these toxic particles will always find cracks within the green filter. These are nasty pollutants. They embed themselves in human tissue and cause all kinds of health problems. They may even result in premature death.

Dr. Maher is positive her research will improve the scientific literature on the importance of trees as urban air filters. However, the reality is that it really doesn’t matter how effective these may be, air pollution will still be a problem to deal with. Of course, if tredges become part of the architectural lingo, schoolgrounds, city squares, and other public spaces will see an improvement in their air quality. This will translate as an improvement in everyone’s health.

This is not where it ends, however. We still must deal with indoors air pollution. Both, the one that comes from the outside and stays with us whenever we open a window to ventilate the livingroom, and the one that is produced indoors by broken appliances, radon filtrations, dirty carpets and so much more.

 

air pollution

AIR8 Air Purifiers

Proposals like Dr. Maher’s can help us ward off dangerous pollutants in our outside spaces, but they do little about indoors air pollution. That is why we at AIR8 have developed a range of products that can take on the task. Our technology uses medical-grade High Efficiency Particle Air filters that eliminates 99,97% of all dangerous particles, such as residues of Nitrogen Dioxide (NO2) and PM 2,5 matter, aerosols, pollen, and all sorts of bacteria. They eliminate any traces of tobacco smoke and traffic pollution that may have sneaked into your home, while pathogens and viruses like Covid-19 are easily filtered and done away with.

By applying the best technology in the medical sector, we ensure that our products keep clients safe and healthy. Low noise and low energy costs are part of our brand, together with the various stages of pre-filtration and HEPA filtration that we use: Activated Carbon and Cold Catalyst, UV-GI light and Ioniser.

AIR8 produces the best protection for any indoors environment, keeping it clean and sanitary. We are backed up by the CE marking in all our products, which have been extensively TÜV tested. We support green proposals like Dr. Maher’s, but we also understand that the problem with air pollution is not limited to the outside world. Whenever an indoor environment needs to be cleaned and protected, an AIR8 HEPA filter will be there for the job.

 

Contact Us

air pollution
Join our weekly newsletter
Contact us
Leave a message, or just your phone no. and we will call you back.
Close button
Close button