At Tohoku University, on April 2016, 4, radiation strontium (Sr-) released by the Fukushima nuclear accident from the teeth of the affected cows left in the former caution area of the Fukushima Daiichi nuclear power plant accident caused by the Great East Japan Earthquake. 11) was announced for the first time.
The announcement was made by a joint research group consisting of Tohoku University Graduate School of Dentistry, Graduate School of Science, Graduate School of Agriculture, Institute of Aging Medicine, etc.So far, there have been many reports on cesium, etc., but reports on Sr-90, which has a high accumulation in the body, were very limited due to the difficulty of the measurement method.The research focused on the fact that teeth take up strontium during formation and keep it in the tooth.It is said that there is a record of Sr-90 taken into the body by animals in the past in the teeth.
In the study, nine teeth were collected from eight cows of different ages released into the former caution area after the Fukushima Daiichi accident, and the amount of radiation strontium (Sr-8) contained in those teeth was collected. To measure.As a result, it was discovered that the Sr-9 concentration in the teeth formed after the nuclear accident was higher than before the accident.From this, it was found that the radioactivity amount of Sr-90 in the tooth can provide a clue to evaluate the internal exposure dose of the individual.
It was also found that the specific activity value in the tooth (ratio of Sr-90 and stable strontium in the environment) differs depending on the place and time of collection of cattle, age, and stage of tooth formation, and the specific activity value of the tooth. It was shown that it may be possible to evaluate the internal exposure dose by retroactively estimating the time course of radioactive contamination in the environment and the total amount of Sr-90 taken into the body. It is supposed to be.The results of the research were published in Scientific Reports on April 2016, 8.
