We assume that contaminated beef has been shipped overseas.  We are also certain that cattle in North America have been grazing on fallout-laden grass for several months now.  Obviously, the levels in North American beef will be much lower than numbers of beef raised in Japan.  This is a moderately informative article regarding the contamination of beef in Japan.  As usual, we need to filter the usual rubbish about not being of any concern.  Cesium 137 is toxic at any dose, even if the dose won’t kill you all by itself.  Comparisons to flying halfway around the world make radiation sound innocuous, but as any flight attendant will tell you, frequent flying accelerates aging.

Once again, I will stress the importance of pectin as the most effective chelator for radioactive cesium.

Do people who have eaten contaminated beef need to worry about their health?

Not unless a person continues to consume tainted beef over a long period of time. As of Thursday, the most highly contaminated beef found contained radioactive cesium of 4,350 becquerels per kilogram, according to the Health, Labor and Welfare Ministry. The meat did not reach the market.

Eating 1 kg of the meat is roughly equal to a radiation dose of 82.65 microsieverts for a period during which radioactive cesium remains in one’s body. If a person eats food with radioactive cesium, half the amount remains in the body for nine days for a baby younger than 1. But the duration gets longer as people age, and it takes 90 days for those aged 50.

The 82.65 microsieverts compares with the 100 microsieverts of radiation a person would be exposed to during a one-way air trip from Tokyo to New York.

Are worries over meat overblown? | The Japan Times Online.