First of all, a study was published on Muration in butterflies around Fukushima. A large number of butterflies showes deformities in larvae and also in adult animals with deformed wings, antennae and eyes in several generations:
Radiation that leaked from the Fukushima nuclear plant following last year's tsunami caused mutations in some butterflies — including dented eyes and stunted wings — though humans seem relatively unaffected, researchers say.The mutations are the first evidence that the radiation has caused genetic changes in living organisms. (via kval.com)
It is likely that the first generation of butterflies suffered both physical damage from radiation sickness and genetic damage from the massive exposure to radioactive isotopes after the disaster, the researchers reported. This generation passed on their genetic mutations to their offspring, who then acquired their own genetic defects from eating radioactive leaves and from exposure to low levels of radiation remaining in the environment. The cumulative effect caused successive generations to develop more serious physical abnormalities. "Note that every generation was continuously exposed," said Otaki.
Mousseau said, "This study adds to the growing evidence that low-dose radiation can lead to significant increases in mutations and deformities in wild animal populations."
The findings are consistent with previous studies in Japan and at Chernobyl, Mousseau added. "The ecological studies that we have conducted found that the entire butterfly community in Fukushima was depressed in radioactive areas, as were the birds, and that the patterns seen in Fukushima were similar to what has been observed in Chernobyl. If the plants and animals are mutating and dying, this should be cause for significant public concern." (via livescience.com)
As a comparison: the highest caesium contamination found in a wild bore in Western Europe after the Chernobyl incident was 4900bq/kg in a Bavarian wild boar. Japanese Fishermen are not allowed to fish in the zone where this fish was caught, but the fishery exclusion zone spreads only a small area of 30 square miles.
Today, Nuclear activists around the world were shocked to hear that:
The operator Tokyo Electric Power Co said Tuesday it had found 25,800 becquerels per kilogram of radioactive caesium in greenling, 258 times higher than the government safety standard. Fishing in waters off the plant has been voluntarily restricted since the nuclear disaster at the plant, which went into meltdown after the March 2011 earthquake and tsunami. Less than a month after the start of the disaster, Tokyo Electric dumped more than 11,000 tons of wastewater containing radioactive substances into the Pacific. (via times.co.za)