fullscreen

eFinder

eFinder

Home › Article

Can houseplants really purify the air in your home? What the science actually says

Daily Maverick · 🇿🇦 public South Africa · · 919 words · By Pedram Vousoughi
headphones Listen to the eFinder podcast briefing
Generate a natural audio summary of this story
Daily briefing

What to know about Can houseplants really purify the air in your home? What the science actually says

The answer, once you examine the actual measurement science behind it, is more interesting than either “yes” or “no”.

Claims checked 11
Techniques found 0
Topics 0

Coverage spectrum

Coverage gap: Low Left coverage
Left0%
Center80%
Right20%

5 sources compared across this story cluster. This is an eFinder estimate from indexed source coverage, not an editorial rating.

What happened

The answer, once you examine the actual measurement science behind it, is more interesting than either “yes” or “no”.

Why it matters

The houseplant-as-air-purifier idea can be traced to a 1989 US study, conducted for Nasa as part of research into closed-loop life support systems for space stations.

Common ground

In sealed, controlled chambers, certain plant species reduced concentrations of volatile organic compounds (VOCs).

Perspective signals

No major persuasion pattern has been attached yet, so the source, headline, and evidence should carry most of the weight for readers.

open_in_new Read the original article: https://www.dailymaverick.co.za/article/2026-05-25-can-houseplants-really-purify…

fact_checkClaims Checked

eFinder analyzed this article and checked 11 claims against available evidence, cross-references, web search, and Wikipedia. Here is what the fact-checking layer found.

check_circle Corroborated 3
verified Verified By Reference 2
info Single Source 2
verified Verified 2
help Insufficient Evidence 1
schedule Pending 1
check_circle
Claim 1: “Portable air cleaners with high-efficiency particulate air (Hepa) filtration can help reduce airborne particles”
CORROBORATED
Confirmed by the US EPA and other technical sources that HEPA filters in portable cleaners reduce airborne particles.
travel_explore
web search NEUTRAL — Jan 13, 2026 ... This type of air filter can theoretically remove at least 99.97% of dust, pollen, mold, bacteria, and other airborne particles with a size of ...
https://www.epa.gov/indoor-air-quality-iaq/what-hepa-filter
travel_explore
web search NEUTRAL — Theoretically, a portable HEPA filter is an ideal and effective method to reduce the indoor PM2.5 level and improve air quality. However, previous studies have ...
https://pmc.ncbi.nlm.nih.gov/articles/PMC9516965/
travel_explore
web search NEUTRAL — Jan 29, 2026 ... HEPA stands for High Efficiency. Particulate Air—a performance definition for filters designed to remove very small airborne particles at a very ...
https://atmotube.com/blog/what-is-a-hepa-filter
+ 1 more evidence source
verified
Claim 2: “The houseplant-as-air-purifier idea can be traced to a 1989 US study, conducted for Nasa as part of research into closed-loop life support systems for space stations.”
VERIFIED BY REFERENCE
Wikipedia and NASA Spinoff sources explicitly confirm the 1989 NASA Clean Air Study focused on cleaning air in sealed environments for space stations.
menu_book
wikipedia NEUTRAL — The National Aeronautics and Space Administration (NASA ) is an independent agency of the U.S. federal government responsible for the United States' civil space program and for research in aeronautics…
https://en.wikipedia.org/wiki/NASA
menu_book
wikipedia NEUTRAL — The NASA Clean Air Study was a project led by the National Aeronautics and Space Administration (NASA) in association with the Associated Landscape Contractors of America (ALCA) in 1989, to research w…
https://en.wikipedia.org/wiki/NASA_Clean_Air_Study
menu_book
wikipedia NEUTRAL — Katherine LaNasa (born December 1, 1966) is an American actress. Since 2025, she has portrayed Nurse Dana Evans in the HBO Max medical drama The Pitt (2025–present), for which she earned a Primetime E…
https://en.wikipedia.org/wiki/Katherine_LaNasa
+ 3 more evidence sources
info
Claim 3: “When a 2019 study modelled plant performance against real-world air exchange rates, it found you would need between ten and 1,000 plants per square metre to match what a building’s passive ventilation already achieves.”
SINGLE SOURCE
The specific statistic (10 to 1,000 plants per square meter) appears only in one web search result which mirrors the claim's phrasing; other search results for '2019 study' are irrelevant (protests, sports, card games).
menu_book
wikipedia NEUTRAL — From 2019 until 2020, protests were held in Hong Kong in response to the Hong Kong government's introduction of a bill to amend the Fugitive Offenders Ordinance in regard to extradition. It was the la…
https://en.wikipedia.org/wiki/2019–2020_Hong_Kong_protests
menu_book
wikipedia NEUTRAL — The PFL 10 mixed martial arts event for the 2019 season of the Professional Fighters League, the 2019 PFL Championship, was held on December 31, 2019, at the Hulu Theater at Madison Square Garden in N…
https://en.wikipedia.org/wiki/PFL_10_(2019)
menu_book
wikipedia NEUTRAL — Phase 10 is a card game created by Kenneth Johnson in 1982, and is sold by Mattel. They purchased the rights from Fundex Games in 2010. Phase 10 is based on a variant of rummy known as contract rummy.…
https://en.wikipedia.org/wiki/Phase_10
+ 3 more evidence sources
help
Claim 4: “Overwatering and poorly maintained pots can contribute to moisture problems or microbial growth indoors.”
INSUFFICIENT EVIDENCE
No evidence was gathered for this claim during the search process.
verified
Claim 5: “It is also helpful if the unit has an AHAM Verifide label, which means its clean air delivery rate (CADR) has been independently tested.”
VERIFIED
AHAM Verifide official sources and Wikipedia confirm that the label indicates the Clean Air Delivery Rate (CADR) has been independently tested.
menu_book
wikipedia NEUTRAL — The clean air delivery rate (CADR) is a figure of merit that is the cubic feet per minute (CFM) of air that has had all the particles of a given size distribution removed. For air filters that have ai…
https://en.wikipedia.org/wiki/Clean_air_delivery_rate
travel_explore
web search NEUTRAL — Room air cleaners certified through the AHAM Verifide® program have been tested by an independent laboratory to ensure the product will perform to the ...
https://ahamverifide.org/why-buy-an-air-cleaner/
travel_explore
web search NEUTRAL — AHAM's standard for measuring an air cleaner's efficacy is called the Clean Air Delivery Rate (CADR). CADR indicates the volume of filtered air an air cleaner ...
https://ahamverifide.org/ahams-air-filtration-standards/
+ 1 more evidence source
verified
Claim 6: “These are chemicals that easily evaporate into the air at room temperature, including some toxic ones like benzene, trichloroethylene and formaldehyde.”
VERIFIED
Web search results from Wikipedia, American Cancer Society, and CDC confirm that benzene is a VOC that evaporates quickly at room temperature. Formaldehyde and trichloroethylene are widely known VOCs.
travel_explore
web search NEUTRAL — Benzene is an organic chemical compound with the molecular formula C 6 H 6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal ring with one hydrogen atom attached to ea…
https://en.m.wikipedia.org/wiki/Benzene
travel_explore
web search NEUTRAL — Benzene is a colorless, flammable liquid with a sweet odor. It evaporates quickly when exposed to air. Benzene is formed from natural processes, such as volcanoes and forest fires, but most people are…
https://www.cancer.org/cancer/risk-prevention/chemicals/benz…
travel_explore
web search NEUTRAL — May 5, 2026 · Benzene is a colorless or light-yellow liquid chemical at room temperature. Signs and symptoms of benzene poisoning depend on how you were exposed. Get clean and get medical care if you …
https://www.cdc.gov/chemical-emergencies/chemical-fact-sheet…
schedule
Claim 7: “Scientific studies suggest they can improve perceived comfort and psychological wellbeing, and in some cases slightly influence humidity or the indoor microenvironment.”
PENDING
This claim was extracted as a checkable statement from the article. eFinder labels it pending based on the available evidence and source context shown below.
check_circle
Claim 8: “Some botanical biofilters, which force air through plant-root substrates with fans, may have useful air-cleaning potential”
CORROBORATED
Multiple sources, including a cross-reference and academic/science-based web results, confirm that active botanical biofilters using fans to force air through root substrates have air-cleaning potential.
travel_explore
web search NEUTRAL — Some botanical biofilters, which force air through plant-root substrates with fans, may have useful air-cleaning potential, but that is a different technology from keeping a few decorative plants on a…
https://theconversation.com/can-houseplants-really-purify-th…
travel_explore
web search NEUTRAL — Active botanical biofilters, systems that use fans to push air through plant root zones, show much more promise because they dramatically increase the rate at which pollutants reach the soil microbes …
https://scienceinsights.org/what-plants-purify-the-air-and-w…
travel_explore
web search NEUTRAL — Research on green technologies for indoor air has highlighted the potential of active botanical biofiltration (ABB) systems, where the air is circulated through the plant root zone as well as the grow…
https://www.frontiersin.org/journals/built-environment/artic…
+ 1 more evidence source
info
Claim 9: “If you also want help with gases or odours, such as VOCs, look for a model that includes an activated carbon filter, because Hepa filters alone are mainly for particles.”
SINGLE SOURCE
The claim is only supported by a cross-reference from the original source; no independent external evidence was provided in the search results to verify the specific comparison of carbon vs HEPA for VOCs.
compare_arrows
cross reference SUPPORTS — If you also want help with gases or odors, such as VOCs, look for a model that includes an activated carbon filter, because Hepa filters alone are mainly for particles.
https://phys.org/news/2026-05-houseplants-purify-air-home-sc…
check_circle
Claim 10: “In sealed, controlled chambers, certain plant species reduced concentrations of volatile organic compounds (VOCs).”
CORROBORATED
Multiple independent sources, including a cross-reference and web search results, confirm that plant species reduce VOCs in sealed/enclosed chambers.
travel_explore
web search NEUTRAL — Volatile organic compounds (VOCs) are significant indoor air pollutants, and employing plants offers a simple and cost-effective approach to reduce their ...
https://pmc.ncbi.nlm.nih.gov/articles/PMC10483372/
travel_explore
web search NEUTRAL — Jan 1, 2024 ... Experiments have showcased the capacity of potted plants to decrease airborne VOC concentrations within enclosed chambers. However, their ...
https://www.sciencedirect.com/science/article/abs/pii/S00489…
travel_explore
web search NEUTRAL — Jul 24, 2025 ... VOCs include a variety of chemicals, some of which may have short- and long-term adverse health effects. Concentrations of many VOCs are ...
https://www.epa.gov/indoor-air-quality-iaq/volatile-organic-…
+ 1 more evidence source
verified
Claim 11: “True Hepa filter, which means it is designed to capture at least 99.97% of very small particles.”
VERIFIED BY REFERENCE
The US EPA and Wikipedia confirm the HEPA standard is designed to capture at least 99.97% of particles of a specific size.
menu_book
wikipedia NEUTRAL — Thai Airways International plc is the flag carrier airline of Thailand. Formed in 1961 as a joint venture between SAS and Thai Airways Company, the airline has its corporate headquarters in Vibhavad…
https://en.wikipedia.org/wiki/Thai_Airways_International
menu_book
wikipedia NEUTRAL — HEPA (, high efficiency particulate air, or high efficiency particulate arresting) is an efficiency standard of air filters. A HEPA filter is an air filter meeting such a standard. A HEPA filter must …
https://en.wikipedia.org/wiki/HEPA
menu_book
wikipedia NEUTRAL — Minimum Efficiency Reporting Value, commonly known as MERV, is a measurement scale designed in 1987 by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) to report …
https://en.wikipedia.org/wiki/Minimum_efficiency_reporting_v…
+ 4 more evidence sources
info Disclaimer: This analysis is generated by AI and should be used as a starting point for critical thinking, not as definitive truth. Claims are verified against publicly available sources. Always consult the original article and additional sources for complete context.