Atsuhiko Takeda

Identification of irradiated pepper with the level of hydrogen gas as a probe

A novel method to detect whether or not a particular pepper has been irradiated has been developed which is based on the fact that H2 is formed in organic substances irradiated with ionizing radiation. Following gamma irradiation, black and white peppers were ground to powder in a gastight ceramic mill. By gas-chromatographic analysis of the gas in the mill, we observed that H2 had been released from the irradiated pepper grains. Curves plotting the H2 content vs storage time at storage temperatures of 7, 22, and 30 degrees C showed that the higher the temperatures, the smaller the H2 content, and that identification of irradiated pepper was possible for 2-4 months after 10 kGy irradiation.

The effect of X-irradiation on the release of lactate dehydrogenase from isolated thymocytes of mice.

Isolated thymocytes and erythrocytes of mice were incubated at 37°C in calcium-free Krebs-Ringer phosphate buffer for 6 hours after x-irradiation. The activities of lactate dehydrogenase (LDH) rele...

Evaluation of Induced Radioactivity in 10MeV-Electron Irradiated Spices (II). .BETA.-Ray Counting.

香辛料の元素組成からリストアップされた10MeV電子線照射により生じる恐れのある (γ, n) 反応由来のβ線放出核種を検出するため照射試料のβ線計測を行った。100kGy照射した2πガスフローカウンタ, 液体シンチレーションカウンタによる計測では誘導放射能は検出されなかった。 (γ, n) 反応の標的核種を含む化合物を照射した場合の誘導放射能の値から, 天然の試料の誘導放射能は無視できるレベルであると考えられた。

Preliminary Examination of Induced Radioactivity in Pepper by 10MeV Electron Irradiation. Mesurement of .BETA.-Ray with Liquid Scintillation Counter.

β-ray measurement was performed on 10 MeV electron-irradiated black pepper and white pepper with liquid scintillation counter in order to reconfirm the wholesomeness of irradiated foods and present unambiguous data to general consumers concerning about the induced radioactivity in the irradiated foods.In irradiated black pepper no radioactivity other than from natural source, un-irradiated one, was detected. But in irradiated white pepper, it was suggested that induced radioactivity might be detected if the detection method was more improved.