The snake plant, known scientifically as Dracaena trifasciata (formerly Sansevieria trifasciata), is a popular houseplant celebrated for its striking, upright foliage and resilience. This plant, often called Mother-in-Law’s Tongue, has gained a widespread reputation for being a powerful, natural air purifier for the home. However, the persistent belief that a single snake plant can significantly filter indoor air quality raises a question: Does scientific evidence truly support this claim in a typical household environment?
The Scientific Basis of Air Filtration
The foundation for the snake plant’s air-cleaning reputation stems primarily from a 1989 investigation known as the NASA Clean Air Study. This research was conducted to explore methods for purifying the air in sealed environments, such as future space stations. Researchers placed plants inside small, airtight chambers and introduced specific toxic chemicals. Under these highly controlled, laboratory conditions, the snake plant demonstrated an ability to absorb various Volatile Organic Compounds (VOCs), including formaldehyde, benzene, and trichloroethylene. The plant absorbs these pollutants not only through the tiny pores on its leaves, called stomata, but also through the action of beneficial microbes living within the potting soil.
Real-World Impact and Limitations
While laboratory tests confirm the plant’s capability, the effect is dramatically different in a real-world setting. A typical home is not an airtight chamber, and modern buildings have a relatively high air exchange rate (ACH), meaning air is constantly swapping with the outside. This constant airflow quickly disperses pollutants, making it challenging for a plant to have a measurable impact. To match the air-cleaning performance of a standard mechanical air filter in a large room, scientific analysis suggests that hundreds or even thousands of potted plants would be necessary. Although the plant is actively absorbing toxins, the rate at which it does so is too slow to compete with the natural ventilation and air movement in a home. Therefore, while the snake plant does possess the mechanism to clean air, its effect on overall indoor air quality is statistically insignificant.
Care and General Household Benefits
Despite the limitations on air purification, the snake plant offers several reliable benefits that make it an excellent houseplant. Its well-earned reputation for being extremely low-maintenance means it tolerates neglect and can thrive in various lighting conditions, from low-light corners to bright, indirect sun. The snake plant utilizes a process called Crassulacean Acid Metabolism (CAM) photosynthesis, which allows it to open its stomata mostly at night to take in carbon dioxide. While the claim that it releases massive amounts of oxygen at night is overstated, this CAM strategy is what makes it a popular choice for bedrooms, as it does not compete for oxygen with a sleeping person. Beyond the physiological effects, the plant’s striking, upright aesthetic improves the visual appeal of a space, and studies show that simply having houseplants present can boost mental well-being, reduce stress, and improve focus.