Effects on people
Significant amounts of radioactivity were released, but prompt evacuation from the immediate area made sure that no member of the public received enough exposure to cause harm. Some 160,000 people were evacuated from their homes and only in 2012 were some allowed limited return. Certain areas are still off limits but the Japanese government has announced it is ready to lift the evacuation order on the first nearby town in April. Radiation was never expected to have any measureable effect on the health of the population and this was confirmed in 2013 by an estimation from the UN Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) that no person in Fukushima prefecture would be exposed, through the environment or their food, to more than 10 mSv in their entire lifetime. This is one tenth of the level at which health effects are known to become more likely, and therefore no measureable increase in cancer rates is expected. The government continues to monitor the health of all Fukushima residents. Stress, worry and the social problems of relocation have been repeatedly identified as the only likely causes of ill health.
Effects on the sea, fishing and food
Groundwater travels naturally from the land to the sea and, in doing so is believed to mingle with heavily contaminated water in the basements of the power plant buildings. This continues to sea and a major effort is underway to identify the routes it is taking and manage groundwater to reduce this to the maximum extent possible. A silt fence has long been in place to prevent contamination reaching the open sea and the diluting effects of ocean currents mean that radioactivity cannot be detected in seawater beyond the plant harbour. Radioactive material continues to run off from the land through rivers to the sea and can be found in certain species of fish. However, all food from affected areas has been strictly monitored since the accident and prevented from sale if in excess of highly conservative standards.
The priority is removal of used fuel from the four storage pools at the top of the reactor buildings and this is well underway at unit 4. In about ten years Japanese technicians expect to be ready to begin removal of the melted core material from inside units 1-3. The four reactors will be decommissioned in 30-40 years, which is typical for any nuclear facility.
Source : World Nuclear News