title: Risk assessment of radioisotope contamination for aquatic living resources in and around Japan.
abstract: Food contamination caused by radioisotopes released from the Fukushima Dai-ichi nuclear power plant is of great public concern. The contamination risk for food items should be estimated depending on the characteristics and geographic environments of each item. However, evaluating current and future risk for food items is generally difficult because of small sample sizes, high detection limits, and insufficient survey periods. We evaluated the risk for aquatic food items exceeding a threshold of the radioactive cesium in each species and location using a statistical model. Here we show that the overall contamination risk for aquatic food items is very low. Some freshwater biota, however, are still highly contaminated, particularly in Fukushima. Highly contaminated fish generally tend to have large body size and high trophic levels.
authors.affiliation: Research Center for Fisheries Management, National Research Institute of Fisheries Science, Fisheries Research Agency, Kanagawa 236-8648, Japan; okamura@fra.affrc.go.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Okamura
authors.affiliation: Department of Mathematical Analysis and Statistical Inference, The Institute of Statistical Mathematics, Tokyo 190-8562, Japan;
authors.forename: Shiro
authors.initials: S
authors.lastname: Ikeda
authors.affiliation: Research Center for Fisheries Oceanography and Marine Ecosystem, National Research Institute of Fisheries Science, Fisheries Research Agency, Kanagawa 236-8648, Japan.
authors.forename: Takami
authors.initials: T
authors.lastname: Morita
authors.affiliation: Department of Mathematical Analysis and Statistical Inference, The Institute of Statistical Mathematics, Tokyo 190-8562, Japan;
authors.forename: Shinto
authors.initials: S
authors.lastname: Eguchi
mesh_terms: D000818:Animals; D049628:Body Size; D002588:Cesium Radioisotopes / Q000032:analysis*; D005399:Fishes; D005507:Food Contamination, Radioactive / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D007564:Japan; D055848:Nuclear Power Plants; D011834:Radiation Monitoring; D018570:Risk Assessment; D014875:Water Pollutants, Radioactive / Q000032:analysis*
chemical_list: D002588:Cesium Radioisotopes; D014875:Water Pollutants, Radioactive
keywords: Weibull distribution; detection limit; radiocesium; random effects; statistical risk assessment