Outdoor air pollution’s impact on public health is well-recorded while in the developed world, indoor air quality is often ignored. But the fact is, especially in the winter when we spend more time indoors, the health of the air inside our homes matters. (Winter is also when cases of carbon monoxide and radon poisoning inside homes spike.)
Indoor air quality is particularly important for people with indoor winter allergies, such as mold, dust and pet danger. These and other compounds in the air can make allergy symptoms worse while exacerbating other respiratory ailments, such as asthma.
Beyond common allergens, volatile organic compounds (VOC) in our indoor air, such as benzene, formaldehyde and trichloroethylene, have been linked to all kinds of issues, including cancer and neurological problems. But due to industrial uses — plus certain amounts of naturally occurring VOCs in the air, water and soil — these compounds are often present inside.
In the 1980s, NASA scientists examined common indoor house plants as a way to promote clean air, with the thought that plants could serve as O2-producing sources on long space flights. The study has served as the benchmark piece of literature on plants and indoor air quality since.
All plants filter the air to some extent, experts say, but certain species were found to be more successful than others at removing harmful compounds when scientists examined the ratio of plant surface area to micrograms of pollution absorbed.
“All plants through their photosynthetic process harvest atmospheric conditions and then filter that out … [they are] hoping to harvest carbon dioxide in order to produce oxygen as a byproduct,” Marc Hachadourian, a plant scientist and a director at the New York Botanical Garden, told weather.com. “[Filtering pollutants] and storing them is sort of a byproduct of the process, just as you or I inhale pollution, and it gets into our bodies.”
NASA’s list of the best plants for absorbing benzene, formaldehyde and trichloroethylene are rounded up in the slideshow above. (You can see a PDF of the original 1988 study here.) As a note, some of the plants are toxic to pets, so research any species before you buy it if you have animals at home.
As far as the effect of these plants on our day-to-day health, Hachadourian said he believes any impact on air quality is probably small though every little bit helps. But he said that, as “plant people” already know, adding green to your space can have other health benefits.
“[Studies report] lower levels of stress for people who work in an office environment with plants than where there are no plants,” he said as an example. “There have also been recent studies about getting outdoors in nature helping stress levels as well. So when it comes down to the bottom line, plants are great to have around for a variety of different reasons.”