The Pothos plant (Epipremnum aureum), also commonly called Devil’s Ivy, is a popular houseplant cherished for its heart-shaped leaves and trailing vines. This resilient plant has long been associated with the ability to cleanse indoor air by removing harmful chemical pollutants. This reputation stems from early scientific investigations exploring the potential for common greenery to improve air quality within enclosed spaces.
The Science Behind the Air Purification Claim
The scientific foundation for Pothos’ air-purifying capabilities comes from the 1989 NASA Clean Air Study. This research investigated methods for cleaning the air within sealed environments, such as space stations, not typical homes. Researchers placed houseplants into small, sealed chambers with high concentrations of specific chemical pollutants. The study successfully demonstrated that plants, including Pothos, possess the potential to remove Volatile Organic Compounds (VOCs) from the atmosphere. However, these findings highlighted a biological mechanism that does not reflect the reality of air cleaning in a typical ventilated building.
How Pothos Removes Specific Indoor Pollutants
Pothos is recognized for its ability to absorb several common Volatile Organic Compounds (VOCs), which are airborne chemicals released from everyday household items. Major VOCs targeted include formaldehyde, which off-gasses from furniture, and benzene and xylene, often found in paints and cleaning products. The mechanism of purification involves a two-part biological process.
The plant’s leaves and stems absorb some pollutants directly through their surfaces and stomata. However, the most significant portion of air cleaning is performed by the root-soil environment. Microbes living in the soil, known as the rhizosphere, metabolize the airborne chemicals, breaking down the hazardous compounds into less harmful substances.
Practical Efficacy in a Home Environment
While the scientific mechanism is valid, the practical efficacy of a few Pothos plants in a typical home is significantly limited. Modern homes and offices feature high air exchange rates (AER), meaning air is constantly exchanged with the outdoors through ventilation and structural leaks. This natural air movement dilutes and removes pollutants far more quickly than a single potted plant can.
To make a measurable impact on air quality in an average-sized room, expert calculations suggest requiring between 10 to 1,000 plants per square meter of floor space. A few plants provide only a supplementary or negligible effect compared to standard ventilation or dedicated air filtration systems. The primary benefit of keeping Pothos is the psychological and aesthetic advantages of having greenery indoors, and should not replace proper ventilation or certified air purifiers.
Toxicity and Safe Placement
A crucial consideration for Pothos owners is the plant’s inherent toxicity to both humans and pets if ingested. The leaves and stems of Epipremnum aureum contain microscopic, needle-shaped structures called insoluble calcium oxalate crystals. When chewed or swallowed, these sharp crystals immediately penetrate the soft tissues of the mouth, throat, and digestive tract.
Symptoms of ingestion include intense burning and irritation of the lips and mouth, excessive drooling, vomiting, and potential swelling. While rarely fatal, the reaction is painful and requires immediate attention, especially in children and animals. To ensure a safe home environment, Pothos plants should be placed in areas completely inaccessible to pets and young children, utilizing elevated locations such as high shelves or hanging baskets.