Photosynthesis – what exactly is that again?
A perfect cycle
We release carbon dioxide and take in oxygen. CO2 against O2 – a perfect cycle that constantly provides us with fresh air. Even when it comes to other waste products, flora has the necessary know-how.
Green liver
Plants absorb pollutants through their roots and store them in leaves or stems. In the Philippines, for example, a plant species extracts nickel from the soil. Rinorea niccolifera thrives where the soil is rich in heavy metals; it has genetically adapted over the course of evolution. Plants are also capable of removing chemicals from polluted soils. One example: poplars purify the soil at a US disposal site for chemical weapons and industrial waste.
Green kidney
How plants make polluted water drinkable again is researched, among others, at TU Berlin. Hornwort, water milfoil, and waterweed, for example, filter toxins, heavy metals, and other pollutants from lakes, ponds, rivers, and even rainwater. The plants have learned to convert harmful substances—and use them for growth.
Green lung
Above all, the (daily shrinking!) rainforests of Asia, Africa, and South America, but also other forests, act like huge filters that cleanse the air of dust, dirt, and harmful particles. Without trees, we could hardly breathe due to traffic, heat, and industrial emissions. What parks and street trees manage for an entire city, smaller plants in your home and workplace can achieve.
Space research
This insight is not new. In March 1788, a speech was heard in Munich: "Better the corruption of the air we breathe, its harmfulness to human health, and the way to improve it easily and quickly." – "The purest air flows from plants," noted the author Karl von Eckartshausen. "It is also known that plants purify the air."
This was proven 200 years later: The US space agency NASA had researched for years ways to purify the breathing air in space stations. In the process, it discovered that some plants are particularly talented at this.
Natural healing methods
To explain what a potted plant can achieve on the Space Station or in the living room, let's take a brief world tour: Decay gases form all around the Earth. Their concentration and composition depend on the geographic location and the nature of the soil. These gases are mainly hydrocarbon compounds. To grow healthily in their environment, plants produce enzymes that decompose toxic substances.
What initially served as a protective function transformed over the course of evolution into a useful function. Plants derive products for their own metabolism (i.e., food) from the breakdown of toxins, releasing the rest as oxygen into the environment. Since decay gases vary greatly, originally identical plants have evolved into subspecies that break down toxins with different intensities.
Room service
Pollutants that contaminate or even poison our indoor air very often occur as hydrocarbon compounds – like the decay gases found in nature. Anyone who wants to breathe more freely indoors just needs to bring the right plants into the house. They prove to be astonishing chemists that produce a variety of useful substances from the most harmful ones. Species that have been proven to purify the air mostly come from tropical and subtropical rainforest zones. There, the roots of many plants lie very shallow in the soil or stretch directly into the air to fish for nutrients.
Foliage
The green air purification takes place via two pathways: On the underside of the plant leaves are openings called stomata, which normally allow CO2–O2-Serve for exchange. Pollutants can enter the interior of the plant through these openings. There they are biochemically decomposed by enzymes. Oxygen and also non-toxic metabolic products are produced, which are stored in the cell walls in the form of organic acids, glucose, etc. That means: air-purifying plants do not poison themselves, but feed on the pollutants.
Root treatment
Much more effective is the toxin uptake in the root area of the plant: soil bacteria and enzymes produced by the root hairs break down toxins into nutrients. This plant food is absorbed by the root as a gall-like mass. The NASA study showed that plants also detoxify indoor air even if their leaves are completely removed. However, air must reach the roots – but since this is excluded in conventional plant pots, we invented the AIRY system for this purpose.
Caution plant?!
Wait a minute! Aren't houseplants even unhealthy because mold easily forms on the potting soil and then fungal spores enter the indoor air? That doesn't happen as long as you care for your plants properly: Please use organic instead of chemical fertilizers and don't overwater! By the way, hydroponics do not offer guaranteed protection: mold thrives here in hiding.
Only a healthy plant can optimally purify indoor air! If you have often overwatered and discovered mold traces on the soil, we recommend leaving chemical agents aside and using a tea that was already considered a remedy in the Inca realm: Boil two heaping teaspoons of the inner bark of the Lapacho tree with 500 ml of water, let it steep and cool, spray the affected substrate surface with it – the fungicidal effect appears within 48 hours.
The author: Peer-Arne Böttcher
Peer is the founder of AIRY and passionate about the topic of healthy indoor air. For many years, he has been intensively engaged with the scientific foundations and technical possibilities of how our breathing air can be sustainably improved – completely without chemicals, filters, or electricity.
