The number of contaminated cattle whose meat was distributed to the poor trusting and innocent residents of Japan has reached 578, and may rise further.
Tonight the news was full of the continuing scandal, brought on by farmers in Fukushima who unknowingly fed their cattle hay that was contaminated with radioactive caesium.
In some cases the contamination was somewhat above the government-set safety levels of 500 becquerels/ kg., e.g. up to 700 becquerels. In a few cases the detected level was much higher, even up to 3,000 becquerels/kg.
But what does that actually mean? Well, if you have spent 45 minutes browsing the net as I have, you will know that it means...not much.
The government-set safety levels are based on the idea that there is 'no safe level' of radiation. Now, nobody has actually shown any negative effects from very low doses of radiation, but what scientists did in the 1950s was extrapolate downwards from the very high doses received in Hiroshima that did kill people or damage their health. It's an exercise akin to observing 50 shots of alcohol in a day will kill 50 % of people (for example), and extapolating linearly downwards and claiming 1 shot will kill 1%. This is obviously wrong for alchohol (hey, I can attest to the benefits of a beer a day), and with radiation it's an unproven idea, but the result is you get things like Japan's very strict safety limits that cause undue panic when they are violated.
This can be demonstrated very easily when you consider naturally occurring radiation. The Japanese are stocking up on brown-coloured underwear right now because beef with levels of radiation of over 500 becquerels per kilo may be in their supermarket. However, even a humble banana contains about 15 becquerels. Eat ten and you already have 150. Eating a hundred bananas at one time (unlikely I grant you) will give you 1,500 becquerels, enough to unleash pandemonium and put you on the nightly news. Coffee has 1000 bq/kg. Half a cup of kidney beans has 30 bequerels. 100 sqm of air in an average Aussie home will give you 3000 bequerels!
Yet again, reality was only given a brief 5 second snippet tonight, when a university professor bluntly stated that you would have to eat a kilogram of this beef every day for a year to have even a barely measurable impact on your health. Of course, if we are considering that level of danger, you may as well take the beef off the market on the grounds that eating much less than that will kill you a lot faster...from arteriosclerosis, colon cancer or gout.