[vdblnkr34 (OP)]

About 70 years ago in Soviet Union lived a person. Who worked on a removal of radiation from metals.

He noticed that length of life of a human depend on how much radiation human body has. But the most interesting he said that our life shortened because of only one radioactive isotope on the planet, which is isotope potassium-40.

isotope potassium-40 is everywhere and in big amounts. The most isotope potassium-40 is in Bananas.

Now i hate bananas. 

Does anyone knows any clues how to get rid of this from human body?

[evan_au]

Potassium is an essential mineral, so you can't get rid of potassium from your diet.

Isotopic separation of Potassium 40 from normal potassium is enormously expensive - and growing all your food with isotopically pure Potassium would be ridiculously expensive. Not economic.

But the reality is that your body suffers many mutations in every cell, every second due to normal metabolism, so a few more due to the decay of Potassium 40 is not going to cause much more problems. Your body is actually quite good at repairing these DNA breaks - and recognizing when it can't, so the cell commits suicide (apoptosis).

If you are concerned about it, work out how much potassium you need, and don't eat more than 10x that amount.
- If you live in a granite area, ensure your basement is well-ventilated so it doesn't build up radon gas, as that can be more damaging than Potassium.
- Standard public health measures like regular exercise, avoiding tobacco, don't use excessive alcohol or other drugs and maintaining a healthy weight will improve your health probabilities.

See: https://en.wikipedia.org/wiki/DNA_damage_(naturally_occurring)

[Bored chemist]

But the most interesting he said that our life shortened because of only one radioactive isotope on the planet, which is isotope potassium-40.

He's wrong.
Most of our radiation exposure comes from outside the body.

It's possible that the stress from worrying about misinformation about potassium (and not eating fruit) will do much more harm than the radiation.

[alancalverd]

Around 10% of your natural radiation dose comes from food, principally from K-40. The good news is that we evolved to cope with background radiation at up to 20 millisievert/year (UK background is 2 - 8 mSv/yr), and that potassium is essential, among other things, to keep your heart beating.   

The extrapolation of dose/harm statistics to very low doses is far from settled. It turns out in practice that people who live in moderately radioactive surroundings (Rocky mountains, average 15 - 20 mSv/yr) live slightly longer than matched controls living at the same altitude in the Appalachian mountains (3 - 5 mSv/yr). The effect is called hormesis and does have some logical basis, but I wouldn't recommend altering your diet one way or the other.   

[vdblnkr34 (OP)]

Yes, you are correct. But, i was taking about the effect of isotope inside the human body. Not outside in the surrounding environment. As an example, one particle of plutonium isotope will slowly kill you, while you can hold plutonium in your hand and nothing will happen.

[vdblnkr34 (OP)]

Jeff Bezos starting program to find immortality in a human. Can you believe that. Soon may we will find out what cause human leave shorter.

[evan_au]

you can hold plutonium in your hand and nothing will happen.

I heard of a nuclear-powered satellite that crashed in a snowy part of the world.
Some people found fragments of the plutonium thermoelectric generator, which remains warm, even in temperatures far below zero.
So they used it as a hand-warmer, and kept it in their coat pocket.
As I recall, it did not go well for them, but I can't find the story with Google 

[Bored chemist]

Jeff Bezos starting program to find immortality in a human.

The fact that he is rich does not indicate that he is clever.

[alancalverd]

Yes, you are correct. But, i was taking about the effect of isotope inside the human body. Not outside in the surrounding environment. As an example, one particle of plutonium isotope will slowly kill you, while you can hold plutonium in your hand and nothing will happen.

That's because plutonium is an alpha emitter, potassium is a gamma source. The range of Pu alphas is a few cell diameters so they do a huge amount of localised damage to living tissue if you ingest active particles, but very little harm to the dead epidermis. The range of gamma rays is much greater so they deposit much less energy in a given volume and there is less difference between internal and external radiation.

Anyway your annual radiation dose from food is about 0.3 millisievert, one tenth of the other major unavoidable  source, radon.

Note that the sievert unit accounts for the relative toxicity of the same dose of different radiations. The consensus ratio is about 20:1 for alpha to gamma but there is (thankfully) very little experimental data and I think the true value is closer to 200:1.

[alancalverd]

Jeff Bezos starting program to find immortality in a human.

The fact that he is rich does not indicate that he is clever.

The number of stupid self-made billionaires is very small.

[Bored chemist]

The number of stupid self-made billionaires is very small.

The number who got a quarter million leg up from the family may be somewhat bigger.

[alancalverd]

A very precise figure. My favorite is a handbag-designing millionairess who, according to the newspapers, started from scratch "with just a £250,000 loan from her dad".

But Bezos is a real entrepreneur with a real degree in engineering. 

My favorite quote from a world gliding champion: "I was lucky. I work hard to be lucky."

[Bored chemist]

Trump- who went bankrupt a few times- is famous for starting with " a small loan of a million dollars from his father."
That would have been sometime around 1965 when a million dollars was a lot of money.
Bezos started with $300,000 from his parents
Musk's dad owned shares in an emerald mine.

Self made billionaires are so rare that it's hard to say anything about their intelligence.

However, most billionaires probably have more sense than to handle plutonium.

[alancalverd]

Bezos started with $300,000 from his parents
Musk's dad owned shares in an emerald mine.

Suggesting that at least someone in the family line had made a load of money without being given it. Unless you believe in financial creationism?

[Bored chemist]

Unless you believe in financial creationism?

Of course I believe in it, they call it "quantitative easing".

Suggesting that at least someone in the family line had made a load of money without being given it.

Well, they made quite a lot of money- or they were given it - possibly inherited from someone who made it unethically.
We simply don't know.
But the point stands; the people who make a lot of money seldom start from "rags" and luck may be as big a feature as brains.

[wolfekeeper]

you can hold plutonium in your hand and nothing will happen.

I heard of a nuclear-powered satellite that crashed in a snowy part of the world.
Some people found fragments of the plutonium thermoelectric generator, which remains warm, even in temperatures far below zero.
So they used it as a hand-warmer, and kept it in their coat pocket.
As I recall, it did not go well for them, but I can't find the story with Google 

I don't think that's ever happened, specifically, but Russia deployed around a thousand thermoelectric generators for stuff like unattended in lighthouses. Many of them have gone missing; some woodsmen did find one that had lost its shielding:

https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator#Theft

e.g.
https://en.wikipedia.org/wiki/Lia_radiological_accident
It went about as well as you'd think.