Punch Q & A on Japan and the nuclear disaster
The Punch put some questions to one of the nation’s nuclear experts - Dr Gerald Laurence. Dr Laurence is a Radiation Safety Adviser and an Adjunct Associate Professor at the University of Adelaide’s School of Chemistry and Physics.
Q) How scared should people in Japan be about the nuclear situation?
A) Not a great deal – the 20-year total of deaths from Chernobyl (from the UN 20-year report) suggests that the radiation related deaths are of the order of a few thousand at most; of the thyroid cancers, mostly in the young 99 per cent were treated & cured (note all the data in the report are strongly disputed by environmental and progessive groups who claim that WHO & IAEA are under the influence of the nuclear industrial complex).
In Japan so far it is spent fuel rods that were removed from the core in November, so iodine-131 (which has an eight-day half life) is not a major risk. The most serious fission product that will be released will be caesium-137 with a 30-year half life.
The possibility of food (rice, milk, etc.) being contaminated because of contaminated fields is real, but public health measures (testing and so on) should mean such produce should not reach the public. Local contamination (houses, towns) will clear at rates dependent on the weather (dissolved in rain, etc.). Local weather also disperses & dilutes the plume (and I assume the Japan Met Bureau can model this very well).
Q) How scared should people outside Japan be?
A) South of the equator – not at all. Air transfer across the equator at sub-stratospheric heights is very slow. Northern hemisphere – the contamination will travel west to east with the normal weather pattern cycles of highs & lows, (it will not reach the jet stream) which means dilution and days for transfer. Levels in North America & Europe will be much less than in areas adjacent to Chernobyl.
Q) Do you think this disaster should be thought off as a once-off occurrence or a chance to rethink nuclear?
A) It depends on your views on risk assessment and risk-benefit analysis. This quake (and tsunami) was possibly the worst ever in Japan – a one in 1000 year or more event. Now we might re-design to cover such an event, but that it could be covered I have no doubt. This was not an immediately human-induced failure like Chernobyl, but design elements that were insufficient to accommodate the extreme natural events.
Q) Are there many misunderstandings in the public about the situation and if so, what’s the biggest?
A) Some misunderstandings about radiation risk are long standing, some currently due to misinformation (see USA Surgeon-General urging people to take iodine supplements, so there is reportedly not an iodine-tablet to be found in some states.[The point here is that iodine to be effective must be taken within a small window of time before exposure to iodine-131. It does not offer general “protection against radiation (see stories of Chinese buying up iodised salt!) and as I suggested above iodine-131 may be only a small component of the contamination mix.
Use of words like “radiation leaking from ...” – radioactive material (contamination) may “leak” – that distinction and the ones about doses and dose rates, scales of comparison and so on are unfortunate, and linked to the long-established public fears of radiation (compared with other harmful materials and exposures).
Q) How do you think this will influence the nuclear power debate in Australia?
A) It will be seen by the opponents of nuclear power as another powerful (pun!) argument against an Australian power program and against uranium exports (racism has shown up in statements from extreme elements such as “if this happens in Japan how much worse it will be in India”
. I would prefer a situation in which the public could properly understand all sorts of risks but that is an idealist position.
Q) Reports from Japan have been conflicting – do you think this is intentional obfuscation or a result of the changing situation on the ground?
Probably a mixture of both (here in Oz we know that we can have conflicting reports on matters from leading members of governments of whatever political type!).
Analysis of the “obfuscation index” needs an expert on Japanese politics, the relationship between Tokyo Electric & the regulatory body, the smooth moves of civil servants from regulator to corporate positions, etc. On the ground measurements are not easy, interpretation probably even more difficult (not just total quantities of fall-out per hectare but the detailed nuclide (isotopic) composition etc.)
Q) What is the best case scenario? What is the worst case scenario?
Best case: Spent fuel rods recovered with water quickly, good meteorological conditions limit immediate spread, and people can deal with the tsunami/quake after-effects. Sadly the world has largely forgotten the thousands dead and selfishly, if understandably, concentrated on “how will I be affected”.
Worst case: Spent fuel rods cannot be water covered; spent fuel from the other reactors become involved, increasing the size of fallout contamination. A nuclear fission driven excursion like Chernobyl is not probable (different design, etc.). Real bad case – long-term psychological damage to the locals, bad enough following Chernobyl, but now with tsunami added. Perhaps the different social traditions between Ukraine & Japan will lead to a different community outcome. I hope so.