higher levels of radioactive cesium in freshwater fish

Japan's Environment Ministry says it detected higher levels of radioactive cesium in freshwater fish than marine fish in disaster-hit Fukushima Prefecture.The ministry on Monday released the results of its study conducted from December last year to February this year. It took freshwater samples in rivers and lakes, as well as at 8 locations in the open sea.The highest amount of cesium, 2,600 Becquerels per kilogram, was found in a goby freshwater fish taken from a river that flows from Iitate Village to Minamisoma City, north of the crippled plant.Some water bugs, which freshwater fish eat, also showed high levels of 330 to 670 Becquerels per kilogram.A type of flounder and bass caught off Iwaki City, south of the plant, registered 260 Becquerels per kilogram-- the highest level for marine fish.A ministry official spoke about the differences in cesium levels in freshwater and marine fish. The official said marine fish are likely to get rid of cesium from their bodies more quickly as they have the ability to excrete salt.The ministry will closely monitor freshwater fish as radioactive cesium may remain in their bodies for a longer period.