16 March, 2011

For those concerned by the nuclear "crisis" in Japan

This reasonable response comes from the British Embassy in Tokyo (remember that we live more than 250km from the site of concern):

I (Paul Atkinson, presumably a Brit here in Tokyo) have just returned from a conference call held at the British Embassy in Tokyo. The call was concerning the nuclear issue in Japan. The chief spokesman was Sir. John Beddington, Chief Scientific Adviser to the UK Government, and he was joined by a number of qualified nuclear experts based in the UK. Their assessment of the current situation in Japan is as follows:

* In case of a 'reasonable worst case scenario' (defined as total meltdown of one reactor with subsequent radioactive explosion) an exclusion zone of 30 miles (50km) would be the maximum required to avoid affecting peoples' health. Even in a worse situation (loss of two or more reactors) it is unlikely that the damage would be significantly more than that caused by the loss of a single reactor.

* The current 20km exclusion zone is appropriate for the levels of radiation/risk currently experienced, and if the pouring of sea water can be maintained to cool the reactors, the likelihood of a major incident should be avoided. A further large quake with tsunami could lead to the suspension of the current cooling operations, leading to the above scenario.

* The bottom line is that these experts do not see there being a possibility of a health problem for residents in Tokyo. The radiation levels would need to be hundreds of times higher than current to cause the possibility for health issues, and that, in their opinion, is not going to happen (they were talking minimum levels affecting pregnant women and children - for normal adults the levels would need to be much higher still).

* The experts do not consider the wind direction to be material. They say Tokyo is too far away to be materially affected.

* If the pouring of water can be maintained the situation should be much improved after ten days, as the reactors' cores cool down.

* Information being provided by Japanese authorities is being independently monitored by a number of organisations and is deemed to be accurate, as far as measures of radioactivity levels are concerned.

* This is a very different situation from Chernobyl, where the reactor went into meltdown and the encasement, which exploded, was left to burn for weeks without any control. Even with Chernobyl, an exclusion zone of 30 miles would have been adequate to protect human health. The problem was that most people became sick from eating contaminated food, crops, milk and water in the region for years afterward, as no attempt was made to measure radioactivity levels in the food supply at that time or warn people of the dangers. The secrecy over the Chernobyl explosion is in contrast to the very public coverage of the Fukushima crisis.

* The Head of the British School asked if the school should remain closed. The answer was there is no need to close the school due to fears of radiation. There may well be other reasons - structural damage or possible new quakes - but the radiation fear is not supported by scientific measures, even for children.

* Regarding Iodine supplementation, the experts said this was only necessary for those who had inhaled quantities of radiation (those in the exclusion zone or workers on the site) or through consumption of contaminated food/water supplies. Long term consumption of iodine is, in any case, not healthy.

The discussion was surprisingly frank and to the point. The conclusion of the experts is that the damage caused by the earthquake and tsunami, as well as the subsequent aftershocks, was much more of an issue than the fear of radiation sickness from the nuclear plants.

And here is an explanation of the radiation levels by a former CAJ student.

EXPLANATION OF RADIATION LEVELS:
- 0-250 millisieverts: no obvious effect
- 250-1000 millisieverts: temporary nausea, damage in blood cells, sterility among men
- 1000-3000 millisieverts: death is possible

Fukushima power plant: radiation dosage of up to 400 millisieverts (dangerous)

Tokyo (Shinjuku): highest level detected was 0.809 microsievert (10 am, 15th)
(in comparison, Chest X-Ray: 40 microsieverts are absorbed)

A microsievert is 1000 times less than 1 millisievert. Although the radiation has risen in the Kanto area and it's good to be cautious, it's also advisable to stay calm as it is not an immediate risk to human health.

Sources:
http://www.niehs.nih.gov/health/docs/energy-good-bad.pdf
http://www.epa.gov/rpdweb00/docs/402-k-07-006.pdf
http://en.wikipedia.org/wiki/Sievert
http://search.japantimes.co.jp/cgi-bin/nn20110315z2.html
http://www.bbc.co.uk/news/world-middle-east-12307698

But keep praying!

5 comments:

Janet said...

This is very reassuring to know - have been worrying about the radiation.

Karen said...

Thanks for putting this up Wendy. It makes a nice change from all the hysterical headlines in the Australian media about the nuclear power plant "melting down" radiation spreading" "out of control" and the like....

Deb L said...

This is really helpful to hear. The headlines here are so frightening. Praying for Japan and for your family daily. I can understand how keeping two active boys relatively housebound would be very hard work indeed.

Wendy said...

Deb, it is worse than two boys, we have three boys! Thanks for your prayers, we need them.

Deb L said...

Shows how observant I am! Sorry about that!