The average adult breathes over 3,000 gallons of air daily, underscoring the importance of maintaining excellent indoor air quality. Among the many methods available to improve the air we breathe, harnessing the power of houseplants is an increasingly popular, natural-based approach. The science behind plants improving indoor air quality primarily revolves around their photosynthesis process and the fact that they absorb various harmful toxins found in the air, an aspect first explored by NASA researcher, Dr. B. C. Wolverton, in the 1980s.
The Role of Photosynthesis
Photosynthesis, the process by which plants convert light energy into chemical energy, is key to understanding how they enhance air quality. During photosynthesis, plants absorb carbon dioxide (CO2) – a gas humans and pets inhale and exhale – and convert it into oxygen. This oxygen release replenishes and improves the indoor air quality, effectively air-filtering the CO2 prevalent in our homes and workplaces.
Beyond their carbon dioxide-lowering capabilities, plants also increase humidity levels through a process known as transpiration. In transpiration, water is drawn up from a plant’s roots to its leaves, where it evaporates into the surrounding environment as water vapor. This increased moisture contributes to a more comfortable indoor climate, particularly in drier areas or months, thus enhancing overall indoor air quality.
Absorption of Indoor Air Pollutants
Plants not only excel in generating oxygen and boosting humidity but also in ridding the air of pollutants. A groundbreaking study by NASA titled “Interior Landscape Plants for Indoor Air Pollution Abatement” identified close to 50 indoor houseplants capable of filtering out common volatile organic compounds (VOCs).
VOCs are harmful pollutants often found in household items like air fresheners, printed materials, paint, varnish, and cleaning products. Some common VOCs include benzene, formaldehyde, trichloroethylene, xylene, and ammonia. Prolonged exposure to these pollutants can lead to health issues such as irritation of the eyes, nose, and throat, headaches, allergies, and more serious conditions involving the kidney, liver, and central nervous system.
Plant-based VOC absorption primarily occurs through tiny openings on plant leaves known as stomata. Present in the leaf’s epidermis, stomata facilitate gaseous exchange in plants. Alongside absorbing carbon dioxide, they also ingest various atmospheric particles, including indoor pollutants.
Once inside the plant, the pollutants undergo ‘phytoremediation,’ where they’re broken down and stored as energy or expelled as harmless byproducts. This robust filtration system, coupled with the fact that plants continually grow and regenerate, enhances their ability to improve indoor air quality consistently.
Microbial Action in Soil
Significantly, it’s not just the green parts of plants that refresh and condition our air. The soil plant roots grow in contributes to air quality too. Root microbiomes – the bacteria and fungi living symbiotically in and around plant roots – further optimize indoor air by degrading and neutralizing pollutants.
As pollutants are absorbed into the plant through the stomata, some make their way down to the roots where root-associated microbes work efficiently to break them down. This microbial detoxification can target even more complex compounds like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs). Through these symbiotic and synergistic processes, plants and their root microbiomes function as air-purifying powerhouses.
Best Plants for Improving Indoor Air Quality
While many plants can improve indoor air quality, some stand out due to their exemplary air-purifying abilities. According to NASA’s Clean Air Study, houseplants such as Spider Plant (Chlorophytum comosum), Snake Plant (Sansevieria trifasciata), Bamboo Palm (Chamaedorea seifrizii), and English Ivy (Hedera helix) are proficient at filtering out formaldehyde.
The Peace Lily (Spathiphyllum wallisii), Pot Mum (Chrysanthemum morifolium), and Gerbera Daisy (Gerbera jamesonii) have shown a particular ability to remove trichloroethylene, benzene, and formaldehyde. The highly adaptable Boston Fern (Nephrolepis exaltata ‘Bostoniensis’) is renowned for its ability to amplify humidity levels and remove xylene and formaldehyde.
Optimal Utilization of Plants for Indoor Quality Improvement
Merely having plants indoors may not be sufficient in improving your indoor air quality. For more effective air filtration, consider having at least one plant per 100 square feet of indoor space. Additionally, placing plants strategically in areas where VOCs are highest – such as the bathroom, kitchen, or newly painted or carpeted spaces – can further enhance their air quality impact.
Proper maintenance of these green air filters is also essential. Regular watering, pruning, and providing adequate sunlight will keep your plants healthy and their phytoremediation capabilities robust.
In conclusion, the role of plants in improving indoor air quality is a science-backed reality that helps create healthier living and working spaces. Their natural air-purification capabilities, especially in an era where indoor pollutants are a growing concern, make them an essential element in environmental management and personal wellness. By understanding the science behind how these green allies improve air quality, we can make more informed choices and contribute towards making our homes and offices cleaner, more breathable sanctuaries.
