title: The thyroid status of children and adolescents in Fukushima Prefecture examined during 20-30 months after the Fukushima nuclear power plant disaster: a cross-sectional, observational study.
abstract: BACKGROUND
  A possible increase in thyroid cancer in the young represents the most critical health problem to be considered after the nuclear accident in Fukushima, Japan (March 2011), which is an important lesson from the Chernobyl disaster (April 1986). Although it was reported that childhood thyroid cancer had started to increase 3-5 yr after the Chernobyl accident, we speculate that the actual period of latency might have been shorter than reported, considering the delay in initiating thyroid surveillance in the then Soviet Union and also the lower quality of ultrasonographic testing in the 1980s. Our primary objectives in the present study were to identify any possible thyroid abnormality in young Fukushima citizens at a relatively early timepoint (20-30 months) after the accident, and also to strive to find a possible relationship among thyroid ultrasonographic findings, thyroid-relevant biochemical markers, and iodine-131 ground deposition in the locations of residence where they stayed during very early days after the accident.
  
  
  RESULTS
  This is a cross-sectional study. We targeted the Fukushima residents who were 18 yr old or younger (including fetuses) at the time of the accident. Our examinations comprised a questionnaire, thyroid ultrasonography, thyroid-related blood tests, and urinary iodine measurement. We analyzed a possible relationship among thyroid ultrasonographic findings (1,137 subjects), serum hormonal data (731 subjects), urinary iodine concentrations (770 subjects), and iodine-131 ground deposition (1,137 subjects). We did not find any significant relationship among these indicators, and no participant was diagnosed to contract thyroid cancer.
  
  
  CONCLUSIONS
  At the timepoint of 20-30 months after the accident, we did not confirm any discernible deleterious effects of the emitted radioactivity on the thyroid of young Fukushima residents. This is the first report in English detailing the thyroid status of young Fukushima residents after the nuclear disaster.
authors.affiliation: Radiation Countermeasures Research Institute for Earthquake Disaster Recovery Support, Hirata, Fukushima, Japan; Kasukabe Kousei Hospital, Kasukabe, Saitama, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Watanobe
authors.affiliation: Faculty of Policy Management, Keio University, Fujisawa, Kanagawa, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Furutani
authors.affiliation: Radiation Countermeasures Research Institute for Earthquake Disaster Recovery Support, Hirata, Fukushima, Japan; Hirata Central Clinic, Hirata, Fukushima, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Nihei
authors.affiliation: Radiation Countermeasures Research Institute for Earthquake Disaster Recovery Support, Hirata, Fukushima, Japan; Hirata Central Clinic, Hirata, Fukushima, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sakuma
authors.affiliation: Hirata Central Hospital, Hirata, Fukushima, Japan.
authors.forename: Rie
authors.initials: R
authors.lastname: Yanai
authors.affiliation: Hirata Central Hospital, Hirata, Fukushima, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: Hirata Central Hospital, Hirata, Fukushima, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Sato
authors.affiliation: Radiation Countermeasures Research Institute for Earthquake Disaster Recovery Support, Hirata, Fukushima, Japan; Hirata Central Clinic, Hirata, Fukushima, Japan; Hirata Central Hospital, Hirata, Fukushima, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Sagawa
mesh_terms: D000293:Adolescent; D000906:Antibodies / Q000097:blood; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D062406:Fukushima Nuclear Accident; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007453:Iodide Peroxidase / Q000276:immunology; D007455:Iodine / Q000652:urine; D007457:Iodine Radioisotopes / Q000737:chemistry; D008297:Male; D012987:Soil / Q000737:chemistry; D011795:Surveys and Questionnaires; D013954:Thyroglobulin / Q000097:blood / Q000276:immunology; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D013964:Thyroid Neoplasms / Q000175:diagnosis; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D014463:Ultrasonography
chemical_list: D000906:Antibodies; D007457:Iodine Radioisotopes; D012987:Soil; D014284:Triiodothyronine; D013972:Thyrotropin; D013954:Thyroglobulin; D007455:Iodine; D007453:Iodide Peroxidase; D013974:Thyroxine