TNP - some figures for cornwall, chernobyl and fly ash

[geoff]

Have you got some real radiation level figures for the above that you mentioned recently?

[The Natural Philosopher]

It's all on the web

Cornwall/Devon is well documented

here's a reference:

average is stated at 7.8msV./yr. I have seen the government itself quote as high as 100msv in certain places:

in Iran is over 200 mSv/yr in places.

ash is a bit more controversial and harder to pin down, but this is a reasonable summary I think

's probably no more dangerous to have a house built of cement and concrete containing fly ash than to eat food prepared on a granite worktop.

Note that in the UK 30% or more of the radiation the average person gets is from Radon as part of the natural radiation decay of uranium in granite style rock. Coal is similar except the burning the coal concentrates the uranium.

As far as Chernobyl goes, while there are hotspots in Pripyat that are dangerous the average level is according to Wiki, about 1uSv/hr.

"A natural concern is whether it is safe to visit Pripyat and the surroundings. The Zone of Alienation is considered relatively safe to visit, and several Ukrainian companies offer guided tours around the area. The radiation levels have dropped considerably, compared to the fatal levels of April 1986, due to the decay of the short-lived isotopes released during the accident. In most places within the city, the level of radiation does not exceed an equivalent dose of 1 ?Sv (one microsievert) per hour."

uSv/hr is about 8.8msV/yr. Comparable to the average in Cornwall for example, and a lot less then the moors where granite rock is near the surface.

Most of the paranoia ultimately revolves around the (mis?)interpretation of the LNT model (Linear No Threshold) which is used as a highly conservative way to regulate radiation release into the environment: This model assumes that death rates to radiation are directly and linearly related to overall dosage, which is spun by the anti-nuclear lobby into 'there no safe level for radiation'.

pretty much becoming discredited as an accurate way to assess actual damage (though its not a bad standard to use for regulatory purposes: If the nuclear industry CAN limit release to less than 1% of what it probably completely safe, whilst still remaining financially viable, why not?).

But it didn't stop its proponents announcing that 'tens if not hundreds of thousands will die as a result of Chernobyl' . When they didn't, this was then spun into a conspiracy of silence by the Russian and Belarus governments etc etc..

That logically this implies both simultaneously believing what governments and scientists say, in terms of the LNT model, and disbelieving it in terms of what the actual death rates are, is an irony completely lost on the anti-nuclear lobby.

Ultimately its all a lot more complicated than just actual radiation levels: you need to know whether that is hot spots or general, and what the emitters are, whether they are things that stick in the body and if so where, or things that rapidly get excreted out to dilute themselves in ground water etc etc.

Oner particle of - sy - plutonium stuck in your lungs is a lot more dangerous than a similar (radioactivity wise) amount of - say - carbon, which although its absorbed, will be absorbed and spread and is something the body is slightly used to as it were.

But this is where you need input from a real radio biologist, not me.

There are some recent studies on cell mutation under the influence of low level radiation that suggest the body is capable of almost complete cell repair up to a certain dose. This is consistent with the fact that there si a sort of parity check system in DNA..its somewhat 'digital;' in . survival of mutations. So like digital TV its error free until a certain point and then massive pixellation happens - and you see cancerous tumours forming.

This (rather crap) picture suggest as well why short bursts of high radiation are far more damaging than prolonged exposure to lower values.

Its becoming pretty well known for example, that radiotherapy that was used to treat cancer 20 years ago, is now showing up as more cancers today. Radiotherapy is quite high dose levels (but of short duration) when all is said and done. It has to be to kill the cells.

[Tim Streater]

[snip useful summary]

Thanks for that. It's something that I hope one of our resident twerps (harry? drivel? can't remember) will read for comprehension.

[The Natural Philosopher]

You can lead a horse to water but you cannot make him drink. You can lead a man to slaughter but you cannot make him think.

(Roy Harper)

[geoff]

Cheers

[Steve Firth]

mentioned recently?

Dunno about him, but the exposures quoted by the NRPB for Cornwall is 7.4 to 10 mSv/year, for Pripyat - the "ghost" city the dose is expressed as

1uSv/h or approximately 9 mSv/year. I note that the figures quoted for Chernobyl tend to quoted either as the exposure immediately after the explosion or the dose is quoted in uSv/year presumably because that looks scary.

[Brian Gaff]

Indeed, some geneticists suggest that much life on the planet relies on sex to reproduce as a way to repair radiation damage which was much greater in times past, and could be greater in the future, if say a star a few light years away blows up. Brian

[tony sayer]

flattened the crap tip;!...

[Theo Markettos]

In case you haven't seen it:

[Chris Hogg]

If you're interested in the geographic distribution of radon in the UK, which is closely related to high background levels of radiation, have a look at

're in Cornwall, in the dark brown stuff!

[Andy Champ]

Well, at least no-one has to live there.

Andy

[Tim Streater]

Didn't you do arithmetic at school?

[The Natural Philosopher]

In today's post Blair world, the default assumption is that the average citizen has trouble in totting up the points in x-factor.(Assuming there are points: I haven't actually ever watched it)

And the implied criticism as elitist of anyone who demands this skill of anyone else.