South Korea's Ministry of Food and Drug Safety has rejected a petition from a civil society group to release the results of radiation testing on fish caught near Japan following the Fukushima Daiichi reactor meltdown.
In 2013, South Korea imposed a ban on the importation of fisheries products from eight Japanese prefectures near Fukushima. Tokyo objected, and petitioned the World Trade Organization for relief, claiming that the ban was unfair to Japanese exporters. The Ministry of Food and Drug Safety has already submitted the results of its testing to the WTO and to Japan as part of the dispute, and advocates claimed that it should be made public as well.
The ministry disagreed. "As the information is related to a case pending at the World Trade Organization (WTO), [it] could lead to a leakage of our strategy to Japan," it said in a statement on Tuesday.
A study of radioactive cesium levels in fish off of Fukushima in 2011 by Pavel Povinec and Katsumi Hirose found that consuming 100 kg of the affected seafood per year (four times the Japanese annual average) would result in approximately the same radiation dose as the world average for background exposure - and roughly the same as the level of exposure from consuming the naturally occuring radioactive polonium in 100 kg of any other seafood.
"Radiation doses from ingestion of marine food are under control, and they will be negligible," the authors concluded.
However, a study published in February by Hiroshi Okamuraa and Shiro Ikedab found that while radioactive cesium levels were overall quite low among most species in Japan, they were unequally distrubuted, with some much more likely to be contaminated than others, especially larger predators towards the top of the food chain. Additionally, effects are regional and vary between freshwater and marine species, the authors said: areas nearer and to the south of the reactor are more affected, and freshwater fish - notably whitespotted char and Japanese eel - are more likely to show higher levels of contamination.