Japanese Prime Minister Shinzo Abe’s government is planning a state secrets act that critics say could curtail public access to information on a wide range of issues, including tensions with China and the Fukushima nuclear crisis.
I then read an August 2013 article in New Scientist:
Ken Buesseler of the Woods Hole Oceanographic Institution in Massachusetts says the Kanda estimate is probably the best he is aware of, and closely matches figures released on 21 August by Tepco, of 0.1 to 0.6 TBq per month for caesium-137 and 0.1 to 0.3 for strontium.
He points out that the north Pacific contains an estimated 100,000 TBq of caesium-137 from H-bomb testing in the 1960s, so the fallout from Fukushima is adding only a fraction of that. Total discharges from the Sellafield nuclear plant in the UK released 39,000 TBq over 40 years, he says.
Buesseler says that during his own sampling survey in waters 30 to 600 kilometres from Fukushima in June 2011, three months after the meltdown, the highest levels he found were 3 Bq of caesium-137 per litre of seawater. By comparison, the natural weathering of rocks results in about 10 Bq of radioactive potassium-40 making it into each litre of seawater.
On an international level, even if all the waste from Fukushima was dumped neat into the Pacific, dilution would eliminate any radiation risks to distant countries like the US, says Simon Boxall of the National Oceanography Centre in Southampton, UK.
For reference, the Hiroshima bomb released about 90 TBq (teraBecquerels) of radioactive material. And Chernobyl in 1986 apparently released between 5 and 14 million TBq. But while Fukushima is adding 0.6 TBq per month, one BBC report gives the total released as 370,000 TBq (as of 12 April 2011), although much of that went into the atmosphere.
Is it dangerous to eat Pacific fish, as some people (e.g. Margo) seem to think? I don’t know, but since I’m someone who habitually downplays the risks associated with smoking and carbon dioxide, it seems only appropriate to also play down the risks of radioactivity from Fukushima.
However, since I equally habitually distrust governments and experts who are currently playing down Fukushima, perhaps I should be alarmed? For while the EPA says there’s “no safe level” of environmental tobacco smoke, it’s recently been raising acceptable thresholds for radioactivity:
But now an update to the 1992 manual is being planned, and if the “Dr. Strangelove” wing of the EPA has its way, here is what it means (brace yourself for these ludicrous increases):
A nearly 1000-fold increase for exposure to strontium-90;
A 3000 to 100,000-fold hike for exposure to iodine-131; and
An almost 25,000 rise for exposure to radioactive nickel-63.
But maybe they’re right to raise the thresholds. For I’m beginning to wonder whether radioactivity really is as dangerous as it’s made out to be, and whether the fear of it may be as overblown as the current hysteria about tobacco smoke.
My reasoning stems from the abundant and apparently normal plant and animal wildlife in the exclusion area around Chernobyl, which remains the largest accidental release of radioactivity.
Chernobyl’s abundant and surprisingly normal-looking wildlife has shaken up how biologists think about the environmental effects of radioactivity. The idea that the world’s biggest radioactive wasteland could become Europe’s largest wildlife sanctuary is completely counterintuitive for anyone raised on nuclear dystopias.
For it seems that, after taking a bit of a knock around the time of the accidents (forests turning red), nature soon bounced back. I watched a documentary [see below] about wolves in the exclusion zone, which found that, apart from the wolves being highly radioactive, the wolf population levels were exactly the same as in a clean reference area, and they were breeding successfully along with beavers and bison. Researchers also found that there were slightly more abnormalities, but on the whole plants and animals were seemingly as healthy as elesewhere, and in fact had slightly higher densities and reproduction rates.
However they did say that, although it was safe for plants and animals (and they actually been adding rare species of horses to the exclusion area), it wasn’t safe for humans. Why’s that? What’s special about humans?
It also reminded me of the populations of theoretical cells I was modelling a year or two back, and my theory of ageing, which was that fast-reproducing cells, which work harder than slow-reproducing ones, gradually get replaced by slower and slower-reproducing cells, so that aged multicellular organisms repair damage more slowly, and also very often shrink in size.
I also found that when an extra background deathrate was imposed on these populations, their reproduction rates didn’t fall so much. Predators act to boost the birthrates of their prey.
And maybe the same applies with background radioactivity? It also presumably imposes an extra deathrate on a population of cells, just like predators on prey, and so increases cell reproduction rates, and slows the ageing process. And when radioactive materials began to appear around 1900, they were actually claimed to have a rejuvenating effect. And perhaps they actually did!
But, since cancers consist of rapidly reproducing cells, it may also be that while a little bit of background radioactivity will slightly boost cell reproduction rates, a lot of it may boost cell reproduction rates to the levels found in cancers. And even higher levels will impose a deathrate on cells that exceeds their birthrate, causing death.
All the same, I’m not planning to buy a packet of caesium-137 when I next go shopping.