[H-TT31] New development of environmental traceability methods

[HTT31-05] Usefulness of strontium isotope composition for determining the geographical origin of Japanese horseradish

*Takafumi KAMITANI¹, Sachiko NAKAMURA¹, Akira ITO¹, Koichi OHYAMA¹, Takuya NISHIJIMA², Kicheol SHIN³ (1.Shizuoka Institute of Environment and Hygiene, 2.Shizuoka Prefectural Research Institute of Agriculture and Forestry, 3.Research Institute for Humanity and Nature)

Keywords:geographical origin, Japanese horseradish (Wasabia japonica), strontium isotopic composition, trace element, Shizuoka prefecture

The geological conditions in Shizuoka prefecture vary widely, from young volcanic rock area in the eastern part to old sediment or metamorphic rock in the western area. Dissolved element and isotopic compositions in springwater, which is located at the top of a river, would reflect the geological characteristics with the exception of effects of atmospheric deposition and human activity. This study aims to evaluate the usefulness of strontium isotope ratio (⁸⁷Sr/⁸⁶Sr) for determining the geographical origin of Japanese horseradish (Wasabia japonica) cultivated in the springs. We collected 58 springwater samples and 59 horseradish samples from 21 sites in Shizuoka prefecture. These samples were subjected to trace elements and ⁸⁷Sr/⁸⁶Sr analyses. The ⁸⁷Sr/⁸⁶Sr values differed, based on the geological characteristics of their site locations, and the value of horseradish sample was well accorded with that of water sample in the same location. The combination of trace element content, e.g. vanadium, and ⁸⁷Sr/⁸⁶Sr value of the horseradish allowed us to distinguish the production area clearly.