Over the past five and a half years, the Fukushima fisheries experimental station analysed fish and shellfish samples. For the first time in years, radioactive cesium levels are within the safety limit.
Tokyo (AsiaNews) – For the first time since the 2011 nuclear disaster, radiation levels in some fish and shellfish samples from Fukushima Prefecture are within the safety limit.
Species including bass, rockfish and stone flounder – sales of which were banned by the central government – were tested between 11 and 28 November, and the prefectural authorities said they all fell below the detection threshold, meaning radioactive cesium was not detected in any samples.
The main reason is that most fish species have undergone a generation change over the past five years with the contaminated marine life dying out, said officials at the prefecture’s fisheries experimental station. The passage of time also helped fish exude radioactive cesium from their bodies.
The prefectural government began testing in April 2011 following the disaster at the Fukushima No. 1 nuclear plant caused the previous month by an earthquake-induced tsunami.
A few days after the first incident, the N. 3 plant experienced a second explosion. In late March 2011, the level of radioactive iodine leaked from the reactor had contaminated coastal waters 1,250 times over the safety limit.
Since then, 40,000 fish and shellfish samples have been checked from 186 species. The initial results indicate that more than 90 per cent of the samples were contaminated with radioactive cesium above the central government’s safety limit of 100 becquerels per kilogram.
Afterwards, the percentage of polluted fish and shellfish declined annually. The tests since April last year showed that the pollution in all samples was within the safety limit.
The monitoring covers seafood caught in 30 locations, in waters with a depth of 5 metres and at a distance of hundreds of meters from the shore, including the area in a 20-kilometer radius of the crippled plant.
“The number of people who are today willing to buy fish from Fukushima is very low,” said Mr. Kazunori Endo, director general of the local Soma Sousou Fishermen’s Cooperative. As a result of this, the local fishing industry has been operating at less than 10 per cent of its capacity.