First time we’ve known for sure. Because it’s finally turned up.
Analysis: 110531e15
Over 3,000 Bq/kilogram combined Sr-89 and 90? I don’t know the general residue due to bomb testing, but it’s not that high. Not nearly.
They announced today, from samples taken three weeks ago. No, I don’t know how this wasn’t seen two months, or even a month ago.
I’d offer them the excuse that perhaps hot debris had to be cleared away for human access to take samples. But that distance is 500 meters away from the stack. And if they’re seeing that much there, you’d expect them to have found lesser amounts further away. That amount is 700 times their lower limit of detection.
Of course, to do that they’d need to be sampling everywhere they could access. And TEPCO hasn’t exactly filled us with confidence.
World's Only Rational Man 
Trying to track down Strontium 90 numbers from nuclear testing. This site looks promising for its bibliography:
http://nicap.org/cm/falloutandCM.htm (Yeah, it seems to be a “sane” tin-foil hat site, but. . .)
Best quantitative quote:
“The total strontium 90 put in the stratosphere as of 1956 amounted to some 12 millicuries (mc) of strontium 90 per square mile, if the activity were spread uniformly over the earth’s surface. This is not the case for the deposits are not uniform. There is a tendency for deposits to peak at equatorial latitudes.
“As of 1956, in the United States the average total deposit appeared to be about 13 millicuries of strontium 90 per square mile, the increase being due to the Nevada tests. See: Radiostrontium Fallout: Project Sunshine, Atomic Weapon Report, July 1956, Wash. 406, by W.F. Libby.”
Holy crap that’s a lot of strontium. Seventy percent falling into the ocean, presumably.
Peak at equatorial latitudes??? So since our bananas are usually from say Equador we’ve all been sucking it up for decades. Well they sure taste yummy!
Bananas probably don’t soak up that much strontium, since potassium (K-40) is always their main dose contributor.
I bet Mike Adams of Natural News would read the above and come to the very scientific conclusion that bananas will doom us all now… 😉 (Please note tongue in cheek in case the written word doesn’t seem sarcastic enough).
Every since I learned that frozen bananas can drive nails, I’ve never trusted the things. They’re sneaky.