title: Perinatal dioxin exposure and psychosocial and behavioral development in school-aged children.
abstract: OBJECTIVE
  The aim of this study was to elucidate the association between psychosocial and behavioral problems in children at school age and dioxin level in breast milk or estimated dioxin exposure (EDE) through breastfeeding in the general Japanese population.
  
  
  METHODS
  Dioxin level of breast milk at 1month of age and breastfeeding ratio through the first year of life were used to calculate the EDE of infants born in 1998-2005 in Japan. The Japanese Social Difficulties Questionnaire (SDQ) for the assessment of children's behavior was sent by mail to mothers whose breast milk underwent the dioxin survey, at the time when their infants were aged 6-13 years.
  
  
  RESULTS
  The study subjects were 175 pairs of mothers and their first infants (79 boys, 96 girls). The mean total dioxin levels of breast milk were 18.3 and 19.8 (pgTEQ/g fat) and EDEs were 16.4 and 19.6 (ngTEQ/kg/year) in boys and girls, respectively. In linear multiple regression analyses after adjusting for age at SDQ, maternal age, birth weight and maternal smoking habit, dioxin level in breast milk was not significantly related to the total difficulties score (TDS) of SDQ in boys, B=2.29 (95% CI -7.60-12.18), or in girls, B=-1.04 (95% CI -9.24-7.15). EDE correlated to the TDS in neither boys, B=-0.99 (95% CI -4.14-2.15), nor girls, B=1.08 (95% CI -2.69-4.85).
  
  
  CONCLUSIONS
  No evidence was found of a correlation between perinatal dioxin exposure and behavioral and psychosocial problems of children measured by SDQ. These results support the benefits of recommending breastfeeding.
authors.affiliation: Department of Pediatrics, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-shi, Tochigi 329-0498, Japan. Electronic address: ykono@jichi.ac.jp.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Kono
authors.affiliation: Department of Pediatrics, Tokyo University, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Oka
authors.affiliation: Department of Neonatology, Toho University School of Medicine, 5-21-16 Omorinishi, Ota-ku, Tokyo 143-8540, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tada
authors.affiliation: Department of Pediatrics, Showa University of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Itabashi
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193, Japan.
authors.forename: Eiko
authors.initials: E
authors.lastname: Matsui
authors.affiliation: Department of Public Health, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-shi, Tochigi 329-0498, Japan.
authors.forename: Yosikazu
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D002648:Child; D002653:Child Behavior Disorders / Q000139:chemically induced*; D002657:Child Development / Q000187:drug effects*; D004147:Dioxins / Q000032:analysis / Q000633:toxicity*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008895:Milk, Human / Q000737:chemistry*
chemical_list: D004147:Dioxins
keywords: Behavior; Breastfeeding; Dioxin; Strengths and Difficulties Questionnaire