The Most Radioactive Places on Earth

Summary

This script explores the realities and misconceptions surrounding ionizing radiation, explaining its measurement in sieverts and microsieverts. It dispels fears about everyday devices like mobile phones and Wi-Fi routers, which do not emit ionizing radiation. The video takes viewers on a journey to some of the world's most radioactive locations, including Chernobyl and Fukushima, revealing surprising facts about radiation levels in these areas compared to everyday life and even the natural background radiation we encounter. It highlights the significant radiation exposure from smoking and emphasizes the relative insignificance of radiation from common sources in our daily lives.

Takeaways

• 📡 A Geiger counter measures ionizing radiation, which has enough energy to remove electrons from atoms and is measured in sieverts.
• ⚠️ Exposure to more than two sieverts of ionizing radiation at once can be fatal.
• 🍌 Bananas contain naturally radioactive potassium, and eating one exposes you to about 0.1 microsieverts of radiation.
• 🌏 Natural background radiation on Earth, including from soil, rocks, air, and space, averages around 0.15 microsieverts per hour.
• 🏙️ Hiroshima's Peace Dome, site of the first nuclear bomb detonation, now has a radiation level of only 0.3 microsieverts per hour.
• 🕳️ An old uranium mine, where Marie Curie obtained her raw material, has a radiation level of 1.7 microsieverts per hour, ten times the natural background.
• 🏜️ The Trinity bomb test site in New Mexico, where the world's first nuclear bomb was detonated, has a radiation level of 0.8 microsieverts per hour.
• ✈️ At high altitudes, such as on an airplane, cosmic rays increase radiation exposure, reaching over three microsieverts per hour at very high altitudes and near the poles.
• 📡 Chernobyl's reactor four meltdown in 1986 spread radioactive isotopes, and the area still detects around five microsieverts per hour.
• 🏥 The hospital in Pripyat, near Chernobyl, where firemen were treated after the disaster, has a radiation level of up to 1500 microsieverts per hour in the basement.
• 🚬 A smoker's lungs receive an average of 160,000 microsieverts of radiation per year due to radioactive polonium and lead in tobacco, the highest dose of ionizing radiation mentioned in the script.

Q & A

What type of radiation does a Geiger counter measure?

A Geiger counter measures ionizing radiation, which is radiation with enough energy to rip electrons off atoms.

What is the unit used to measure ionizing radiation exposure?

Ionizing radiation exposure is measured in units called sieverts.

What is the approximate radiation exposure from eating a banana?

Eating a banana exposes you to about 0.1 microsieverts of radiation, which is one ten millionth of a sievert.

What is the average global level of natural background radiation?

The level of natural background radiation in Sydney is about 0.15 microsieverts per hour, which is roughly the average globally, usually ranging between 0.1 and 0.2 microsieverts per hour.

How does the radiation level in Hiroshima compare to the natural background radiation?

The radiation level in Hiroshima, almost 70 years after the nuclear bomb was detonated, is only 0.3 microsieverts per hour, which is slightly higher than the average natural background radiation.

What is special about the radiation level in an airplane?

The level of radiation inside an airplane can increase with altitude due to less atmosphere shielding from cosmic rays, reaching over three microsieverts per hour at higher altitudes and towards the poles.

What is the radiation level near the Chernobyl nuclear reactor number four?

The radiation level near the Chernobyl nuclear reactor number four is around five microsieverts an hour, which is comparable to the dose received from a dental x-ray.

How does the radiation exposure in Fukushima compare to Chernobyl?

Although the release of radioactive material in Fukushima was less than Chernobyl (only about 10%), the readings are up around 5 to 10 microsieverts an hour because the accident is much fresher and less of the radioactive material has decayed.

What is the most radioactive place the speaker visited?

The most radioactive place the speaker visited was the basement of the hospital at Pripyat, where the firemen's clothing from the Chernobyl disaster was stored, with readings of 1,500 microsieverts an hour.

Who receives the highest levels of ionizing radiation on average?

On average, a smoker's lungs receive the highest levels of ionizing radiation, approximately 160,000 microsieverts worth of radiation every year, due to the radioactive polonium and lead in tobacco.

What is the comparison between a CT scan and natural background radiation?

In a CT scan, the patient receives about 7,000 microsieverts, which is equivalent to three years' worth of natural background radiation.

Outlines

00:00

📡 Understanding Ionizing Radiation and Its Everyday Exposure

This paragraph discusses the concept of ionizing radiation, which is capable of removing electrons from atoms and is measured in sieverts. It clarifies that everyday objects like mobile phones and Wi-Fi routers do not emit ionizing radiation, as detected by a Geiger counter. The script introduces the concept of natural background radiation, including the example of bananas containing trace amounts of radioactive potassium. It uses the banana as a unit of measurement to explain the relative scale of radiation exposure, mentioning that sleeping next to someone results in a higher exposure than sleeping alone due to their natural radioactivity. The video also touches on the natural ionizing radiation present in the environment, including from the earth, rocks, air, and space, with Sydney's level cited as an average global example. The paragraph concludes with a teaser about visiting the most radioactive places on earth, starting with Hiroshima's Peace Dome, where the first nuclear bomb was detonated, and an old uranium mine where Marie Curie obtained her materials, both having relatively low radiation levels compared to common fears.

05:01

✈️ Radiation Exposure in Unusual Places and Its Effects

The second paragraph explores the unexpected places where high levels of ionizing radiation can be found, starting with airplanes where cosmic rays increase with altitude, leading to higher radiation exposure at cruising altitudes, especially near the poles. The script then discusses the Chernobyl nuclear disaster, explaining the aftermath and the current radiation levels in the area, which are comparable to a dental x-ray's dose for a one-hour exposure. It also covers the Fukushima exclusion zone, where radiation levels are higher due to the more recent accident, and the measures taken to remove topsoil to reduce radiation. The video script describes a visit to the hospital in Pripyat, where the clothing of firefighters who fought the Chernobyl fire is stored, and the extraordinarily high radiation levels in the basement of this building. The paragraph ends with a comparison of radiation exposure from various sources, including CT scans, the additional exposure people around Fukushima might receive over their lifetime, and the yearly limit for US radiation workers, before revealing that astronauts and, surprisingly, smokers receive some of the highest levels of ionizing radiation due to tobacco's radioactive content.

10:05

🚭 The Surprising Truth About Radiation Exposure from Smoking

In the final paragraph, the video script reveals that the average smoker's lungs receive the highest dose of ionizing radiation, largely due to the radioactive polonium and lead present in tobacco. This fact is highlighted to emphasize the multiple harmful effects of smoking, including exposure to carcinogens, toxins, and high levels of radiation. The paragraph also serves as a segue into the presenter's personal project, a documentary about his travels to places like Chernobyl and Fukushima, which will be released the following year. The script concludes with a recommendation for the book 'The Day of the Triffids' and a promotional offer for Audible, an audiobook service, thanking them for their support and the viewers for watching.

Keywords

💡Radiation

Radiation refers to the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization. In the context of the video, radiation is the central theme, with the script discussing various sources and levels of ionizing radiation that people encounter in everyday life and in specific locations like Chernobyl and Fukushima. The video aims to educate viewers about the different types of radiation and their potential effects on human health.

💡Geiger counter

A Geiger counter is a device used for detecting and measuring ionizing radiation. It is named after the two German physicists who invented it, Hans Geiger and Walter Müller. In the script, the Geiger counter is used to illustrate the presence and levels of ionizing radiation in various environments, emphasizing that common household items like mobile phones and Wi-Fi routers do not emit ionizing radiation that would register on the device.

💡Ionizing radiation

Ionizing radiation is a type of radiation with enough energy to ionize atoms or molecules, which means it can strip electrons from atoms, creating ions. This is a key concept in the video, as it differentiates between harmful and harmless types of radiation. The script explains that ionizing radiation is what a Geiger counter measures and that exposure to high levels can be deadly, while low levels are a natural part of our environment.

💡Sieverts

Sieverts is the unit of measurement for the biological effect of low levels of ionizing radiation on the human body. It quantifies the health effects of radiation doses. The video uses sieverts to convey the relative danger of different radiation levels, with the script stating that exposure to more than two sieverts at once is likely to be fatal.

💡Bananas

In the video, bananas are used as a humorous and relatable example to illustrate the concept of naturally occurring, low-level ionizing radiation. Bananas contain potassium, some of which is naturally radioactive. The script mentions that eating a banana exposes a person to about 0.1 microsieverts of radiation, which is a very small amount compared to the natural background radiation.

💡Background radiation

Background radiation refers to the ionizing radiation present in the environment from various natural sources, such as soil, rocks, and cosmic rays from space. The script uses the concept of background radiation to provide a baseline for comparison when discussing the radiation levels in different locations, such as Sydney and the Chernobyl exclusion zone.

💡Hiroshima Peace Dome

The Hiroshima Peace Dome, also known as the Genbaku Dome or Atomic Bomb Dome, is part of the Hiroshima Peace Memorial Park and is a remnant of the original structure that survived the atomic bombing in 1945. The video script mentions the Peace Dome to contrast the historical significance of the site with the relatively low levels of radiation present there today.

💡Uranium mine

A uranium mine is a type of mine where uranium, a naturally occurring radioactive element, is extracted from the ground. The script discusses an old uranium mine where Marie Curie obtained her raw material for research. The mine is highlighted as a place with higher levels of ionizing radiation due to the presence of uranium ore.

💡Marie Curie

Marie Curie was a pioneering physicist and chemist who conducted groundbreaking research on radioactivity. She is mentioned in the script as having worked in a lab where traces of radioactivity still remain, particularly on a doorknob and the back of her chair, illustrating the lasting effects of her work with radioactive materials.

💡Trinitite

Trinitite is a green glassy material formed from the desert sand that was fused by the intense heat of the first atomic bomb test, conducted at the Trinity site in New Mexico. The script uses Trinitite as an example of the lasting physical effects of nuclear explosions and as a source of slightly elevated radiation levels.

💡Chernobyl

Chernobyl refers to the site of the 1986 nuclear disaster at the Chernobyl Nuclear Power Plant in Ukraine. The video script discusses the long-term effects of the disaster, including the spread of radioactive isotopes and the ongoing detection of radiation in the area. Chernobyl serves as a stark example of the potential dangers of high-level ionizing radiation exposure.

💡Fukushima

Fukushima refers to the Fukushima Daiichi Nuclear Power Plant in Japan, site of a severe nuclear accident in 2011 following a massive earthquake and tsunami. The script mentions the Fukushima exclusion zone and the efforts to collect and remove topsoil contaminated with radioactive material, highlighting the ongoing challenges of managing the aftermath of a nuclear disaster.

💡Smokers

The video concludes with a surprising fact: that the lungs of smokers receive the highest annual dose of ionizing radiation on average, due to the radioactive polonium and lead present in tobacco. This serves as a powerful conclusion to the video's exploration of radiation, emphasizing that even seemingly mundane activities can expose individuals to significant levels of radiation.

Highlights

Radiation from everyday objects like mobile phones and Wi-Fi routers is not detected by a Geiger counter because they do not emit ionizing radiation.

Ionizing radiation, which can remove electrons from atoms, is measured in sieverts and exposure to over two sieverts can be fatal.

Bananas contain naturally radioactive potassium, resulting in a radiation dose of about 0.1 microsieverts when eaten.

Natural background radiation varies globally, with Sydney's level at 0.15 microsieverts per hour.

Hiroshima's Peace Dome has a radiation level of 0.3 microsieverts per hour, almost 70 years after the nuclear bombing.

Uranium mines, like the one where Marie Curie obtained her raw material, have higher radiation levels, around 10 times the natural background.

Marie Curie's lab still has areas that are radioactive, such as a doorknob and the back of her chair.

The Trinity bomb test site in New Mexico has a radiation level of 0.8 microsieverts per hour.

At high altitudes, such as on an airplane, the radiation level increases due to less atmospheric shielding from cosmic rays.

Chernobyl's reactor four has a current radiation level of around five microsieverts per hour, comparable to a dental x-ray.

Fukushima's exclusion zone has radiation levels of 5 to 10 microsieverts per hour, higher than Chernobyl due to the accident's recency.

The hospital in Pripyat, near Chernobyl, is one of the most radioactive places on earth with readings of up to 1500 microsieverts per hour.

A CT scan exposes a patient to about 7000 microsieverts, equivalent to three years of natural background radiation.

People living around Fukushima are estimated to receive an additional 10,000 microsieverts over their lifetime due to the nuclear disaster.

Astronauts on the space station receive about 80,000 microsieverts of radiation over six months.

Smokers' lungs receive an average of 160,000 microsieverts of radiation per year due to radioactive polonium and lead in tobacco.

Smokers receive the highest dosage of ionizing radiation compared to residents of Fukushima, Chernobyl, radiation workers, and astronauts.

The documentary filmed in locations like Chernobyl and Fukushima was inspired by the book 'The Day of the Triffids'.

Audible is offering a one-month free trial and a free book download to support the documentary project.

Transcripts

Radiation is frightening.

At least, certain types of it are.

I mean my Geiger counter doesn't go off near my mobile phone, or the Wi-Fi router or my

microwave.

That’s because a Geiger counter only measures ionizing radiation — that is, radiation

with enough energy to rip electrons off atoms.

And it’s measured in units called sieverts.

If you're exposed to more than two sieverts all at once you'll probably die shortly after

that.

But we’re exposed to low levels of ionizing radiation all the time.

Bananas for example are rich in potassium and some of that potassium is naturally radioactive.

So when you eat a banana you're actually exposed to about 0.1 microsieverts of radiation.

That’s one ten millionth of a sievert.

Let’s use a banana for scale of radiation doses.

You know, since people eat bananas we become radioactive too.

So you're actually exposed to more radiation if you sleep next to someone than if you sleep

alone.

But I wouldn't worry about that because that dose is insignificant compared to the natural

background radiation of earth.

I mean there’s ionizing radiation coming out of the soil in the rocks, in the air,

and even from space.

The level of radiation here in Sydney is about .15 microsieverts per hour, and that's about

average globally.

The level’s usually between .1 and .2 microsieverts per hour.

But there are places with significantly higher levels.

So who on earth do you think receives the maximum dose of ionizing radiation?

Let’s answer that question by going to the most radioactive places on earth.

Some places you’d expect to have high levels of radiation might surprise you.

I’m in Hiroshima and that is the Peace Dome.

It was about 600 meters above that dome where the worlds first nuclear bomb was detonated

over a city.

It was detonated there to have maximum destructive impact.

Well the level of radiation today almost 70 years later is only 0.3 microsieverts per

hour.

I'm about to get into an elevator.

We're going down in a mineshaft.

This is an old uranium mine.

This is the mine where uranium was discovered.

It's also the place where Marie Curie obtained her raw material.

1.7 microsieverts per hour.

That's about 10 times the natural background that you would have.

Nowadays most of the uranium has been removed.

But in this wall there’s still a small piece and you can see under UV light it floresces.

Look at that.

Fluorescent uranium ore.

This is the lab of Marie Curie.

She won two Nobel prizes, one in physics and one in chemistry.

And she conducted a lot of her work here.

And this is her office.

She would have sat right there.

Apparently there are only a few parts of this area which are still radioactive.

One is this doorknob.

Well it climbs not not much but — But that's like 10 times the background.

Yeah.

More than 10.

And another is the back of her chair.

You can still detect alpha particles coming off this spot right here.

Apparently after she was working in the lab she would come, oopen the door leaving traces

of radium here and then go and pull out her chair.

Welcome to New Mexico.

This is the Trinity bomb test site where the world’s first nuclear bomb was set off.

Right here.

Right in the spot.

This whole area was vaporized.

In fact, there was so much heat liberated by that bomb that it fused all of the desert

sand into this green glass.

And you can still find it here.

They've actually named this mineral after the test.

It's called Trinitite.

Yeah.

This is the only place on earth that this has ever been made.

The level of radiation here is about 0.8 microsieverts an hour.

The Trinitite itself is a little bit more radioactive.

I got readings of two or three microsieverts an hour off them.

Now which place has higher levels of radiation then anywhere we've seen so far?

The answer is an airplane.

You know, as you gain altitude there's less atmosphere above you to shield you from cosmic

rays.

So the level of radiation inside the plane can go up to 0.5 microsieverts per hour at

18,000 feet, up to one microsievert per hour at 23,000 feet, over two microsieverts per

hour at 30,000 feet, and over three microsieverts per hour at even higher altitudes and towards

the poles.

That is Chernobyl nuclear reactor number four.

It melted down on April 26, 1986.

So, what happened was so much heat was generated inside that reactor that it basically blew

the top off spreading radioactive isotopes throughout this whole surrounding area and

over into Europe.

And that is why we can still detect the contamination here today.

Now, right now it's reading around five microsieverts an hour.

If I stayed here for one hour my body would receive a similar dose to what you’d receive

when you get a dental x-ray.

So this is not a huge amount of radiation.

And one of the reasons why the radiation level is not too high is because they actually removed

a couple meters worth of topsoil from this whole area, then they dumped it somewhere.

That's why we can stand here.

We're driving into the Fukushima exclusion zone now.

I'm just watching as the levels on my Geiger counter go up as we approach the zone.

See those black bags at the side of the road?

The Japanese are doing now exactly what the people in Chernobyl did, collecting up meters

and meters of topsoil.

The mask is probably overkill.

It's just to stop radioactive dust from getting into my lungs.

This is definitely one of the most radioactive places where I've been.

Even though the release of radioactive material was less than Chernobyl, only about 10%, because

it's much fresher—only three years since the accident— much less of it has decayed.

So I've been getting readings up around 5 to 10 microsieverts an hour.

And I think we won't be staying here for too long because of that.

I'm about to go into the hospital at Pripyat.

And this is where the firemen were taken after they fought the fires at the Chernobyl reactor.

And in the basement of this building they have left all the firemen's clothing.

Once they realize it was so contaminated they chucked it down there.

(Inaudible) But you can see there's a huge pile of their gear there.

Right outside the door I'm getting 500 microsieverts an hour just outside the door.

One thousand five hundred microsieverts an hour.

You know if we stayed here for a couple hours we’d receive our annual dose of background

radiation.

That basement was the most radioactive place I visited and it's one of the most radioactive

places on earth.

If I'd stayed down there for one hour I would’ve received 2000 microsieverts.

That's a years worth of natural background radiation.

Every yellow pixel here represents a banana.

Now that might seem like a lot, but consider that in a CT scan the patient receives about

7000 microsieverts.

That's three years worth of natural backround radiation.

It's been estimated that the people living around Fukushima will receive an additional

10,000 microsieverts over their lifetime due to the nuclear power disaster.

For comparison US radiation workers are limited to a maximum of 50,000 microsieverts per year.

But that's less than another occupation.

Astronaut.

An astronaut on the space station for six months will receive about 80,000 microsieverts

worth of radiation.

But not even they are exposed to the highest levels of ionizing radiation.

So can you guess who is?

The answer is a smoker’s lungs.

A smoker’s lungs on average receive 160,000 microsieverts worth of radiation every year.

That's due to the radioactive polonium and radioactive lead in the tobacco that they're

smoking.

So not only are they exposed to carcinogens and toxins they also receive very high levels

of radiation.

So it's not the people of Fukushima or Chernobyl or radiation workers or even astronauts that

receive the highest dosage of ionizing radiation.

That honor goes to your ordinary average smoker.

Hey.

As you can see over the last few months I've been traveling around the world actually filming

a documentary for television.

It should be on in the middle of next year.

But being in places like Chernobyl and Fukushima reminded me of this book The Day of the Triffids

and it's about a post-apocalyptic world in which plants take over.

I know it sounds like a crazy idea but it's actually a brilliant book so you should really

check it out if you're looking for something to do over the holidays.

Now you can download this book for free by going to audible.com/Veritasium or you can

pick any other book of your choosing for a one month free trial.

Audible is a great audiobook website with over 150,000 titles in all areas of literature

including fiction, nonfiction, and periodicals.

So I really want to thank audible for supporting me and I want to thank you for watching.