title: Effect of the Fukushima nuclear power plant accident on radioiodine (¹³¹ I) content in human breast milk.
abstract: BACKGROUND
  Environmental pollution with radioiodine (iodine-131, (131) I) occurred after an accident at the Fukushima nuclear power plant (FNP) on March 11, 2011, in Japan. Whether environmental pollution with (131) I can contaminate human breast milk has not been documented.
  
  
  METHODS
  The (131) I content was determined in 126 breast milk samples from 119 volunteer lactating women residing within 250 km of the FNP, between April 24 and May 31, 2011. The degree of environmental pollution was determined based on the data released by the Japanese government.
  
  
  RESULTS
  An (131) I content of 210 Bq/kg in the tap water in Tokyo, which is located 230 km south of the FNP, on March 22 and of 3500 Bq/kg in spinach sampled in a city located 140 km southwest of the FNP on March 19 decreased over time to <21 Bq/kg on March 27 and 12 Bq/kg on April 26, respectively. Seven of the 23 women who were tested in April secreted a detectable level of (131) I in their breast milk. The concentrations of (131) I in the breast milk of the seven women were 2.3 Bq/kg (on April 24), and 2.2, 2.3, 2.3, 3.0, 3.5 and 8.0 (on April 25); the concentrations of (131) I in the tap water available for these seven women at the same time were estimated to be <1.3 Bq/kg. None of the remaining 96 women tested in May exhibited a detectable concentration of (131) I in their breast milk samples.
  
  
  CONCLUSIONS
  The contamination of breast milk with (131) I can occur even when only mild environmental (131) I pollution is present.
authors.affiliation: Department of Obstetrics and Gynecology, Kitasato University, School of Medicine, Sagamihara, Japan.
authors.forename: Nobuya
authors.initials: N
authors.lastname: Unno
authors.forename: Hisanori
authors.initials: H
authors.lastname: Minakami
authors.forename: Takahiko
authors.initials: T
authors.lastname: Kubo
authors.forename: Keiya
authors.initials: K
authors.lastname: Fujimori
authors.forename: Isamu
authors.initials: I
authors.lastname: Ishiwata
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Terada
authors.forename: Shigeru
authors.initials: S
authors.lastname: Saito
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Naoki
authors.initials: N
authors.lastname: Kunugita
authors.forename: Akihito
authors.initials: A
authors.lastname: Nakai
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Yoshimura
mesh_terms: D000328:Adult; D004190:Disasters; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000032:analysis*; D007564:Japan; D008895:Milk, Human / Q000737:chemistry*; D055848:Nuclear Power Plants; D018788:Radioactive Hazard Release
chemical_list: D007457:Iodine Radioisotopes