Bioaccessibility of radioactive cesium in soils

Takahara, Shogo  ; Ikegami, Maiko*; Yoneda, Minoru*; Kondo, Hitoshi*; Ishizaki, Azusa  ; Shimada, Yoko*

Doses received by the public are necessary information in management of radiation exposures in areas contaminated by the Fukushima Daiichi Nuclear Power Plant (1F) accident. Direct ingestion of contaminated soil is one of the exposure pathways which is a concern for the people living in the areas in terms of children's exposure. Therefore in order to manage efficiently the middle and the long term exposures with a sense of safety of the people, we have to clarify the contribution of this pathway to the doses received by those. However, a fractional absorption of radioactive cesium in gastrointestinal system has not been evaluated yet. We evaluated this factor based on the results of a physiologically based extraction test and an extraction test with hydrochloric acid, which is adopted in Japanese national law to evaluate a fractional absorption of heavy metals in gastrointestinal system. In addition, we assessed the doses to the public from this pathway after the 1F accident.