Everybody knows by now that electronic devices with displays like cell phones and computers give off radiation and people have been looking for ways to reduce their exposure. A NASA study is claimed to report that some plants absorb this harmful radiation and protect the user. Cactus in particular were very efficient at absorbing radiation.
How effective are cactus and what is the best way to use them for protection? Are they as good as other plants?
Analysis of Cactus Absorbing Radiation
I found the following claims on the internet.
Did you know that NASA tested, and proved, that some indoor plants can absorb radiation?
Cactus is well known as an efficient absorber of radioactive waves, thanks to an in-depth study done by NASA. It is especially useful for absorbing the radiation that is produced by computers.
Cactus also absorbs the radiation that may be coming from nearby cell phone towers, so it is truly a plant that protects you from a wide range of radiation.
When you hear a story such as this, it is very useful to break it down into components. In order for a cactus to protect you from radiation coming from a computer several things need to be true.
- Computers have to produce radiation.
- Such radiation needs to be harmful, or else there is nothing to protect.
- Cactus need to be able to absorb this radiation and reduce your exposure to it.
Do Computers Produce Radiation?
Light is a form of radiation, and monitors are designed to send out light, so yes they do produce radiation.
However, light is not the radiation that is of concern here. People are concerned about electromagnetic (EM) energy, but the claims for cactus protection never seem to mention EM radiation. I suspect the authors making the claims don’t understand different forms of radiation.
You might have noticed that one of the above quotes refers to “radioactive waves”. I can’t find any definition of such a wave. I suspect the author has heard of radio waves, and believes they are dangerous, and therefore they must be radioactive – just my guess. There is no such thing.
Science Questions for Surprising Answers reports that computers do give off the following radiation:
- 400 to 800 THz electromagnetic radiation. This is the visible light given off by the laptop’s screen that makes it possible for you to see what the computer is displaying. Yes, ordinary visible light is a form of radiation.
- 10 to 100 THz electromagnetic radiation. This is the infrared radiation given off by all parts of the laptop due to their temperature, through the everyday process of thermal emission.
- 5 GHz or 2.4 GHz electromagnetic radiation. These are the radio waves given off by the WIFI antenna in the laptop, which are used to connect to a wireless network.
- 2.4 GHz electromagnetic radiation. These are the radio waves given off by the Bluetooth antenna in the laptop, which are used to connect wirelessly to peripheral devices such as a cordless mouse.
- Low frequency electromagnetic radiation. These are the radio waves that leak from the electronic circuitry inside the laptop.
- Nuclear radiation including gamma rays. This is the nuclear radiation emitted through the natural radioactive decay of atomic isotopes in the computer’s materials.
Is Electromagnetic Radiation Harmful
“EMFs occur naturally and also come from manmade sources. Scientists have found some possible weak connections between low-level EMF exposure and health problems, like cancer.”
Setting your labtop right on your lap may not be a good idea. Extensive use of cell phones right next to your ear may cause problems. Notice how vague these statements are.
“According to the latest research, EMFs are unlikely to cause any adverse health effects. You should feel safe using your cell phone, and appliances. You should also feel safe if you live near power lines, as the EMF frequency is very low.”
This chart compares different sources of ionization radiation. A year of exposure from your computer CRT (this is the old large monitor) is 1/5 that of a dental X-ray, and 1/40 as much as a flight from LA to New York. The natural potassium in your body will give you a dose 400 times as much as that CRT. Today’s flat screens produce even less radiation.
It is unlikely that sitting in front of your computer, on a desk, is causing you any harm.
Do Cactus Absorb EM Radiation?
Yes, but then most things will absorb EM radiation, especially things that contain water. An aquarium would work better than a cactus. A cup of coffee also works.
How Do You Stop Electromagnetic Radiation
EM radiation travels in a straight line, just like light. The amount of radiation also follows the inverse square law that says doubling the distance from the emitting object will lower the radiation to 1/4. A simple way to reduce radiation from your computer is to move farther away from it. That is why a cell phone in your back pocket is not nearly as much of a concern as one held next to your brain, and why a laptop on the desk is much safer than one on your lap.
The other way to reduce radiation is to block it. Put something between you and the computer. If you hold a big piece of cardboard between you and the computer you will be exposed to less radiation. Holding a cactus between you and the computer has a similar effect.
Putting a cactus beside your computer has no effect since it does not block the radiation reaching you. If it’s not blocking the visible light from the screen it’s also not blocking EM radiation.
So a cactus works, provided you hide the screen with it. But then how do you see the screen? In practical terms a cactus does not reduce radiation from a computer.
This conclusion is based on what we know about this type of radiation, which is quite a bit. But if you still have some doubts, this video will show you a simple test; measuring EM radiation from a computer with and without a plant.
Other Plants Also Reduce Radiation
Cactus are not the only plant that is claimed to reduce radiation, but all of the comments above regarding cactus also apply to these other plants. They don’t work either.
What About the NASA Study?
I looked hard and long for a NASA study that looked at cactus and radiation from a computing device, and found nothing. One site did reference the NASA study that looked at a plants ability to absorb chemicals from the air, and somehow leaped from this to a discussion about plants that reduce radiation, but at least they did include the reference they were using. I suspect this is what other authors have also done. If you find such a study, please let me know in the comments below.