Name: 携帯電話はがんの原因になる？ (Do Cell Phones Cause Cancer?)
Uploaded: 2021-01-14T06:48:07.000Z
Duration: 4 min 1 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

A lot of people worry that their cell phone will give them cancer, which isn’t all that

I mean, you’re holding a device that emits radiation right next to your brain! Terrible

Some kinds of radiation /can/ damage DNA, which can then lead to cancer. But your cell

phone doesn’t give off that kind of radiation.

And even if there /was/ a way that cell phone radiation could hurt you, studies have shown

Cell phones communicate with cell towers using a form of radiation known as radiofrequency,

The word “radiation” is just in there because it’s a type of energy on the electromagnetic

The spectrum goes from low energy at one end to high energy at the other. Radio and microwaves

are near the low end. Gamma rays and X-rays are near the high end.

It can help to think of electromagnetic radiation as a wave, with a certain frequency based

The higher the energy, the higher the frequency.

When an electromagnetic wave hits an atom, it transfers some energy to that atom. When

the wave has a high enough frequency -- meaning, it has lots of energy -- it can transfer enough

energy to the atom to knock out an electron.

Electromagnetic energy that can knock out electrons is called ionizing radiation, and

it can break chemical bonds in your cells and damage your DNA.

In other words, it’s the cancer-causing kind.

When electromagnetic energy /doesn’t/ have a high enough frequency to break chemical

bonds, it’s called non-ionizing radiation.

If non-ionizing radiation hits an atom, it isn’t going to be able to knock out an electron.

So it can’t damage cells, and it can’t cause cancer.

It doesn’t matter how strong the beam of radiation is. Its ability to knock out electrons

only depends on its frequency, which isn’t affected by the intensity of the radiation.

It’s like how, no matter how powerful your microwave is, it’s never going to start

emitting infrared radiation -- which would be the next level up in frequency.

The cutoff between ionizing and non-ionizing radiation is somewhere in the ultraviolet

range. That’s above visible light in frequency, and wayyyy above the radio waves that cell

Which is why, based on what we know about physics and biology, there’s nothing cell

However, doctors and scientists do take the potential health risks of cell phones seriously, and

a lot of studies have been done to see if there’s a link between cell phones and cancer.

Sometimes, these studies do find what /sounds/ like a relationship between cell phones and

For example, one study of a million women in the UK found what seemed to be a weak link

to a tumor called an acoustic neuroma [nur-OH-ma], a benign tumor in the nerve that leads from

More frequent cell phone use was correlated with a higher risk of getting this tumor.

But the study followed the subjects for seven years. If there actually was a connection

between this tumor and cell phone use, you’d expect more people to develop the tumor

as they were exposed to more radiation over time.

Based on that, and the fact that other large studies haven’t found the same connection,

the authors of the study concluded that it was a statistical fluke.

Another large study from the World Health Organization found an increase in glioma -- a

type of nerve cell tumor that’s responsible for most cases of malignant brain cancer -- among

They collected data by having people report their own cell phone use, and people tend

Plus, people who used their cell phone infrequently had a lower risk of glioma than

If cell phone radiation was causing the tumors, that wouldn’t make any sense.

And the vast majority of other studies have found no evidence that cell phones can cause

There’s also the fact that if cell phones were causing some kinds of cancer, we’d

be seeing the rates of those cancers go up.

I mean, something like 5 billion people use cell phones, and they’ve been commercially

available since the mid-1980s. That’s long enough for cancer to start showing up, even

That’s exactly what happened after cigarettes started being mass-produced. Lung cancer used

to be pretty rare, but when smoking cigarettes started to become more popular, lung cancer

There just isn’t any sign of this when it comes to cell phones. Both the number of people

who get brain cancer, and the number of people who die from it, is holding steady even as

So go ahead. Make as many phone calls as you want.

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