Anyone who owns a pet knows they’ll sniff and sample just about anything within their reach.

That’s why, when you consider indoor plants that clean air, you should bear in mind the health of your pet, too.

Some of the most popular houseplants known to improve air quality and remove indoor toxins could be poisonous if ingested.

There are almost twice as many ornamental plants considered toxic than safe, according to a publication of the University of California and the California Poison Control System, “Know Your Plants – Safe or Poisonous.”

Still, you can choose among many popular favorites known to purify the air and filter out harmful chemicals that won’t harm your pet.

Here’s a partial list of plants considered safe by the California Poison Control System:

  • African violet
  • Areca palm
  • Bamboo
  • Boston fern
  • Cast iron plant
  • Flame violet
  • Fuschia
  • Gardenia
  • Gerber daisy
  • Gloxinia
  • Lady palm
  • Prayer plant
  • Velvet plant
  • Spider plant
  • Yucca
You have to be careful when considering certain varieties.

For instance, NASA rates a few palms among its top 10 indoor plants that clean air. The national space agency began studying the correlation between houseplants and indoor air pollution some 20 years ago. 

Among NASA’s findings, the Areca palm and the bamboo palm effectively remove chemical toxins while releasing water into the air as humidifiers.

But, beware of the Sago palm, which is apparently very tasty to animals in addition to being toxic. The seeds of the Sago palm are especially poisonous, according to the American Society for the Prevention of Cruelty to Animals (ASPCA).

Another example is the Boston fern. It effectively removes chemicals and humidifies, but the asparagus fern has poisonous berries. Similarly, the Boston Ivy — like other types of ivy — makes an appearance on a number of poisonous plant lists.

The spider plant is tops for removing formaldehyde, found in foam insulation, plywood, even grocery bags, facial tissue and paper towels. Just don’t confuse it with the toxic spider lily.

Speaking of lilies, the peace lily often is cited for its ability to remove volatile organic compounds but its sap can cause intense burning of the mouth and skin irritation, excessive drooling, vomiting and difficulty swallowing, according to the ASPCA.

Similarly, don’t let the biblical-sounding angel’s trumpet and star-of-Bethlehem plants fool you. They are highly toxic, along with the clearly-labeled poison primrose, devil’s ivy, deadly nightshade and crown of thorns. 

In addition to plants with berries, some poisonous flowering plants can be particularly appealing to pets because of their fragrance.

Examples include chrysanthemums, gladiola, daffodil, tulips and carnations, philodendron, and most notably the extremely toxic azalea, part of the rhododendron family.

While combating formaldehyde in plywood and foam insulation, azaleas can cause acute digestion problems along with weakness, depression and paralysis. Severe poisoning can lead to coma and death, according to the ASPCA.

Not all flowering plants are poisonous, of course. The daisy makes the UC list of toxic plants that can cause skin rash or irritation. On the other hand, the Gerber Daisy is not only safe, but also effectively removes trichloroethylene, often associated with dry cleaning.

For more information on plants that are dangerous to dogs and cats, check out “Know Your Plants – Safe or Poisonous?”

For a list of appropriate plants, check out this list of safe and poisonous plants.

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