The radiation lie


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Radiation's Big Lie

Did a Nobel laureate knowingly lie about the dangers of radiation in 1946?

BY Steven Cherry // Fri, October 07, 2011

In 1946, Hermann Muller was awarded the Nobel Prize in medicine for work done on spontaneous gene mutation, including the effects of X-rays.

So Muller was the obvious guy to go to when, right around the same time, the National Academy of Sciences formed a committee to offer expert advice to the government on the biological effects of atomic radiation.

In his Nobel acceptance speech and in the NAS committee meetings, Muller argued that there is no safe level of radiation exposure, a position the Academy came to adopt. That in turn influenced official policies toward radiation for decades.

The problem is, Hermann Muller knowingly lied. So says Edward J. Calabrese, a professor of toxicology at the University of Massachusetts School of Public Health. He bases that opinion on a wealth of materials, including formerly classified files and, recently, some overlooked correspondence between Muller and one of his coresearchers.

Professor Calabrese is the author of over 600 journal papers and more than a dozen books. He?s board certified in toxicology, is the editor in chief of the journal Human and Ecological Risk Assessment, is a member of three different toxicology societies as well as the Society of Risk Analysis, and he?s my guest today.

This interview was recorded 29 September 2011.

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Obviously there are safe radiation levels. Our own cells are radioactive, because they all contain Potassium and Carbon, both of which have naturally occuring radioactive isotopes in significant amounts (K40 and C14). We would be harmful to ourselves. :laugh:

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It's not the background stuff they're talking about but the low level exposures normally found at high altitudes, in most radiation related work environments, etc. Stuff people panic over now.

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I still want to know how Apollo astronauts safely made it thru the Van Allen Belts -- if they did. :ermm:

If they went through fast enough they would only be exposed to dangerous levels for a very short time.

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I still want to know how Apollo astronauts safely made it thru the Van Allen Belts -- if they did. :ermm:

http://en.wikipedia.org/wiki/Van_Allen_radiation_belt#Implications_for_space_travel

The Apollo astronauts traveled through the Van Allen radiation belts on the way to the moon; however, exposure was minimized by following a trajectory along the edge of the belts that avoided the strongest areas of radiation. The total radiation exposure to astronauts was estimated to be much less than the five (5) rem set by the U.S. Atomic Energy Commission for people who work with radioactivity.
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If they went through fast enough they would only be exposed to dangerous levels for a very short time.

I still want to know how Apollo astronauts safely made it thru the Van Allen Belts -- if they did. :ermm:

This is one of those great conspiracy questions that I have always wanted to know an answer to, and Lexcyn's answer is actually the best I think I've ever heard on the subject.

How radioactive is that belt supposed to be anyway?

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Exposure is a function of flux, exposure time, the shielding material used and the scatter radiation produced by it. Sometimes you're better off with more energetic radiation which is less easily absorbed than less energetic scatter radiation created by shielding attempts that is almost completely absorbed.

The flux is largely a mix of energetic protons and electrons trapped in Earths magnetic field. These can generate a spray of less energetic particles and x-rays when they hit matter, including shields and spacecraft hulls, especially metals.

Shields incorporating hydrogen-rich dense polymers (polyethylene etc) and metals containing lithium (spacecraft are a lithium-aluminum alloy) are pretty effective. A new kid on the block is hybrid polymer shielding, which supposedly be used in lieu of lead for x-rays but actually be thinner/lighter.

http://www.canlaser.com/en/GammaRay.aspx

The inner belt is as low as 100 km (62 miles) and is where ISS lives and where commercial spacecraft like SS2 etc. will fly. We have plenty of experience with shielding for it.

At Earth's 11.2 km/s escape velocity and with the outer margin of the outer belt being 12,000 - 60,000 km you're out of them in less than 90 minutes. The altitude varies because of variations in the solar wind, solar flares and other effects.

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  • 2 weeks later...

always had a sneaking suspicion that the Van Allen belts and radiation in space are like our sea dragons, hydras, and kraken. they're on the maps just because people are scared of the unknown and think there be monsters there, but once you go you realize it's not that bad.

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Off the dial.

Useful.

The actual value is about 25 Sv/year - not safe, but you aren't going to go through the middle of them are you?

For reference the Fukushima maximum reported radiation was ~400 Sv/year.

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