Environmental Behavior of the Radionuclides Released from the Fukushima Daiichi Nuclear Power Plant Accident

• Published in: RADIOISOTOPES Vol. 63; no. 6; pp. 299 - 316
• Main Author: YAMAZAKI, Hideo
• Format: Journal Article
• Language: English; Japanese
• Published: Japan Radioisotope Association 15.06.2014
• Subjects: INW, Japan, Honshu, Tokyo Bay; INW, Japan, Honshu, Kanto Region
• ISSN: 0033-8303; 1884-4111
• DOI: 10.3769/radioisotopes.63.299

The environmental behavior of radioactive nuclides released from the Fukushima Daiichi Nuclear Power Station(FDNPS) accident in eastern Japan was investigated. The radioactive pollution of environmental samples, including airborne dust, soil, sediment, fish, and other organisms was described. It was evaluated for environmental behavior and fate of the radioactive material from the spatial and temporal distribution of the radioactive nuclides. In Higashiosaka City about 600km away from FDNPS, it begins to detect the radioactive nuclides in the airborne dust from 25th March 2011. Radioactive fission products 95Zr-95Nb was detected on 18th April. The concentrations of 131I, 134Cs, and 137Cs in the soil collected from Fukushima City were 126000, 14000, and 14200Bq/kg on 19th March 2011 and 12800, 13200, and 13700Bq/kg on 26th March 2011, respectively. The concentrations of 131I, 134Cs, and 137Cs in the soil samples collected from March-June 2011 from study sites in metropolitan area and Kanto region ranged from nd to 91900, 59 to 16100, and 69 to 17600Bq/kg, respectively. (Concentrations of 131I were done decay correction to the value of 16th March) Radioactivities in fish samples collected from off FDNPS, Tokyo Bay, and Kejonuma Pond were measured. The radioactive contamination of forest ecosystem was also investigated. Two processes are involved in the radioactive contamination of the environment from the FDNPS accident. One is contamination by radioactive nuclides released from the hydrogen explosion. Leakage of contaminated cooling water to the ocean is in other important environmental pollution. We must continue carefully monitoring of radioactive nuclides in the environment.