Minamisoma, Japan, 4/4/2011 Ms. Sagara, a local farmer worried that her crops are irratiated, asks Greenpeace to take samples of her vegetables to test for contamination.

I move between states of shock and awe at the disaster unfolding at the Fukushima nuclear reactors. The pictures from the reactor site are terrifying, and the stories of heroism by the workers racing to contain a full-scale meltdown are moving. Greenpeace's monitoring team last week identified dangerous levels of radiation 25 miles from the reactors and prompted the IAEA to echo recommendations that Japan expand its evacuation zone.

Media coverage of the dangers of radiation has at times seemed to echo the nuclear industry's claims that small amounts of radiation are not harmful. Even the more balanced commentators have accepted the nuclear industry's claim that there are "safe" levels of radiation. An ABC report last week had powerful footage: the story of an organic farmer who hung himself; people ignoring evacuation orders. What struck me is that the reporter glosses over the radioactive Iodine found in milk in Washington State and California. Scientific studies again and again have shown that radiation is dangerous and causes cancer.

A comprehensive study by the National Academy of Sciences concludes:

that the current scientific evidence is consistent with the hypothesis that there is a linear, no-threshold dose-response relationship between exposure to ionizing radiation and the development of cancer in humans.

And, according to Christopher Busby, from the European Committee on Radiation Risk and an expert on ionizing radiation, the Fukushima disaster may be felt for a long time.  He estimates that for people living within 100km (or 62 miles) of Fukushima:

assuming these people remain living there for one year the number of excess cancers predicted...is approximately 200,000 in the  next 50 years with 100,000 being diagnosed in the next 10 years. If they are evacuated immediately, the number will fall by a significant amount.

NHK reports that the Japanese government is withholding data showing high levels of radioactivity that would require increasing the evacuation zone.  Our radiation monitoring team will continue to provide an an independent assessment of the health risks of radiation in the area around Fukushima.