Research Overview and Reports

3] Study on the Area Transfer Coefficients of 11 Species of Wild Edible Plants in Fukushima

Published in: Scientific Reports, 12, Article number: 5171 (2022)
Paper Introduction Author: Momo Takada, Geosphere Chemistry Research Group

A paper on the surface migration coefficients of 11 types of wild vegetables in Fukushima was published in *Scientific Reports*.

Title

Area Transfer Coefficients of 137Cs in Edible Wild Plants and Their Time Dependence Following the Fukushima Daiichi Nuclear Power Plant Accident
(Aggregated transfer factor of 137Cs in edible wild plants and its time dependence after the Fukushima Dai-ichi nuclear accident)

Authors

Momo Takada a, Tetsuo Yasutaka a, Seiji Hayashi b, Mai Takagi b, Keiko Tanagami c

  1. National Institute of Advanced Industrial Science and Technology (AIST)
  2. National Institute for Environmental Studies
  3. Quantum Science and Technology Research Development Organization

Abstract

 The authors determined the aggregated transfer factors (Figure 1) for 11 species of edible wild plants commonly found in the Tohoku region (5 herbaceous species, bamboo shoots, 2 woody species, and 3 fern species), which will aid in predicting future concentrations of radioactive cesium in these plants.To calculate the area transfer coefficients, we used food monitoring data from the Ministry of Health, Labor and Welfare from 2012 to 2019 and deposition data from aerial surveys conducted in 2012.The areal transfer coefficients for bamboo shoots, herbaceous plants, and ferns showed a decreasing trend with a half-life of approximately two years, whereas those for woody plants did not exhibit a clear temporal change. Therefore, the areal transfer coefficients calculated using data from 2014 onward were shown to be applicable for estimating long-term radioactive cesium intake due to their gradual decline. As shown in Table 1, the areal transfer coefficients ranged from 6.1 × 10⁻⁵ to 5.2 × 10⁻³ m²/kg-fresh, with the highest value observed for Japanese spindle tree and the lowest for butterbur. Woody plants tended to have higher area transfer coefficients than herbaceous plants and ferns.

Figure 1: Schematic diagram of the area transfer coefficient
Table 1: Surface transfer coefficients for various wild mountain vegetables (from the paper)
Wild Vegetable Names Scientific Name Category Surface Transfer Coefficient (m²/kg-fresh)
Koshiabura Chengiopanax sciadophylloides Woody plants 5.2 × 10−3
Japanese aralia Aralia elata Woody plants 4.3 × 10⁻⁴
Japanese bracken Osmunda japonica Ferns 4.2 × 10⁻⁴
Bamboo shoots Phyllostachys spp. 3.9 × 10⁻⁴
Water-leaved Elatostema (Mizu) Elatostema umbellatum Herbaceous plants 3.6 × 10⁻⁴
Maple-Leaf Parasenecio (Sidoke) Parasenecio delphiniifolius Herbaceous plants 2.5 × 10⁻⁴
Kusasotetsu (Kogomi) Matteuccia struthiopteris Ferns 2.0 × 10⁻⁴
Bracken Pteridium aquilinum Ferns 1.9 × 10⁻⁴
Butterbur buds Petasites japonicus Herbaceous plants 1.7 × 10⁻⁴
Udo Aralia cordata Herbaceous plants 1.1 × 10⁻⁴
Butterbur Petasites japonicus Herbaceous plants 6.1 × 10⁻⁵

[Acknowledgments]
 We would like to express our gratitude to the local residents of the Yamakiya district in Kawamata Town and Iitate Village for their cooperation in the field surveys. This research was supported by a Grant-in-Aid for Scientific Research (JSPS KAKENHI) Grant No. 18H04141.

[Original Publication]
https://www.nature.com/articles/s41598-022-09072-5


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