Sorry, Plant Parents: Study Shows Houseplants Don’t Improve Air Quality

sagarmanis/iStock via Getty Images
sagarmanis/iStock via Getty Images

Sometimes accepted wisdom needs a more thorough vetting process. Case in point: If you’ve ever heard that owning plants can improve indoor air quality in your home or office and act as a kind of organic air purifier or cleaner, you may be disappointed to learn that there’s not a whole lot of science to back that theory up. In fact, plants will do virtually nothing for you in that respect.

This botanic bummer comes from Drexel University researchers, who just published a study in the Journal of Exposure Science and Environmental Epidemiology. Examining 30 years of previous findings, Michael Waring, an associate professor of architectural and environmental engineering, found only scant evidence that plants do anything to filter contaminants from indoor air.

Many of these studies were limited, the study says, by unrealistic conditions. Plants would often be placed in a sealed chamber, with a single volatile organic compound (VOC) introduced to contaminate the air inside. While the VOCs decreased over a period of hours or days, Waring found that the studies placed little emphasis on measuring the clean air delivery rate (CADR), or how effectively an air purifier can “clean” the space. When Waring converted the studies' results to CADR, the plants's ability to filter contaminants was much weaker than simply introducing fresh air to disperse VOCs. (Additionally, no one is likely to live in a sealed chamber.)

The notion of plants as natural air filters likely stemmed from a NASA experiment in 1989 which argued that plants could remove certain compounds from the air. As with the other studies, it took place in a sealed environment, which made the results difficult to translate to a real-world environment.

Plants can clean air, but their efficiency is so minimal that Waring believes it would take between 10 and 1000 of them per square meter of floor space to have the same effect as simply opening a window or turning on the HVAC system to create an air exchange. Enjoy all the plants you like for their beauty, but it’s probably unrealistic to expect them to help you breathe any easier.

Amazon's Best Cyber Monday Deals on Tablets, Wireless Headphones, Kitchen Appliances, and More

Amazon
Amazon

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Cyber Monday has arrived, and with it comes some amazing deals. This sale is the one to watch if you are looking to get low prices on the latest Echo Dot, Fire Tablet, video games, Instant Pots, or 4K TVs. Even if you already took advantage of sales during Black Friday or Small Business Saturday, Cyber Monday still has plenty to offer, especially on Amazon. We've compiled some the best deals out there on tech, computers, and kitchen appliances so you don't have to waste your time browsing.

Computers and tablets

Amazon

- Amazon Fire HD 10 Tablet 64GB; $120 (save $70)

- Amazon Fire HD 8 Tablet 64GB; $84 (save $35)

- HP Pavilion x360 14 Convertible 2-in-1 Laptop; $646 (save $114)

- HP Pavilion Desktop, 10th Gen Intel Core i3-10100 Processor; $469 (save $81)

- Acer Nitro 5 Gaming Laptop; $973 (save $177)

Headphones and speakers

Beats/Amazon

- Bose QuietComfort 35 II Wireless Bluetooth Headphones; $200 (save $100)

- Sony Bluetooth Noise-Canceling Wireless Headphones; $278 (save $72)

- JBL LIVE Wireless Headphones; $100 (save $30)

- JBL Charge 4 - Waterproof Portable Bluetooth Speaker; $120 (save $10)

- Bose SoundLink Color Bluetooth Speaker II; $79 (save $50)

- Powerbeats Pro Wireless Earphones; $200 (save $50)

Video Games

Sony

- Watch Dogs Legion; $30 (save $30)

- Marvel's Avengers; $27 (save $33)

- Ghost of Tsushima; $40 (save $20)

- The Last of Us Part II; $30 (save $30)

TECH, GADGETS, AND TVS

Samsung/Amazon

- Amazon Fire TV Stick; $30 (save $20)

- Echo Show 8; $65 (save $65)

- Nixplay Digital Picture Frame; $115 (save $65)

- eufy Smart Doorbell; $90 (save $30)

- Samsung 75-Inch Class Crystal 4K Smart TV; $898 (save $300)

home and Kitchen

Ninja/Amazon

- T-fal 17-Piece Cookware Set; $124 (save $56)

- Le Creuset Enameled Cast Iron Curved Round Chef's Oven; $180 (save $136)

- Ninja Foodi 10-in-1 Convection Toaster Oven; $195 (save $105)

- Roborock E4 Robot Vacuum Cleaner; $189 (save $111)

- Instant Pot Max Pressure Cooker 9 in 1; $80 (save $120)

- Shark IZ362H Cordless Anti-Allergen Lightweight Stick Vacuum; $170 (save $110)

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How Much Is the Earth Worth?

The New York Public Library, Unsplash
The New York Public Library, Unsplash

Our home planet may be the most precious place we know, but it isn't priceless. The Earth's resources and the value it offers to humans add up to some unknown, tangible cost. The species may never have to worry about buying or selling the world, but thinking of it in terms of concrete numbers can help us better understand its value. Now, as Treehugger reports, one scientist has developed a special formula that allows us to do just that.

According to the calculations of Greg Laughlin, an assistant astronomy and astrophysics professor from the University of California, Santa Cruz, the Earth is worth roughly $5 quadrillion (or $5,000,000,000,000,000). He came up with that price after gauging the planet's mass, temperature, age, and other factors that directly correlate to its ability to sustain life.

To emphasize just how valuable the Earth is, Laughlin also estimated the worth of other planets in our solar system. Our nearest neighbor Mars costs about the same as a used car at $16,000. That's a fortune compared to Venus, which he appraised at the meager value of one cent.

Laughlin doesn't expect these numbers to have applications in the real world. Rather, he hopes they will inspire people to better appreciate the only home they know. He's not the first person to put a massive, hypothetical price tag on something just for fun. The cost of the Death Star from Star Wars has been calculated at $852 quadrillion—many times Laughlin's estimate for Earth.

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