title: Perinatal dioxin exposure and the neurodevelopment of Vietnamese toddlers at 1 year of age.
abstract: Dioxin concentrations remain elevated in both the environment and in humans residing near former US Air Force bases in South Vietnam. This may potentially have adverse health effects, particularly on infant neurodevelopment. We followed 214 infants whose mothers resided in a dioxin-contaminated area in Da Nang, Vietnam, from birth until 1 year of age. Perinatal exposure to dioxins was estimated from toxic equivalent (TEQ) levels of polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/Fs-TEQ), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TetraCDD) concentrations in breast milk. In infants, daily dioxin intake (DDI) was used as an index of postnatal exposure through breastfeeding. Neurodevelopment of toddlers was assessed using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). No significant differences in neurodevelopmental scores were exhibited for cognitive, language or motor functions between four exposure groups of PCDDs/Fs-TEQ or 2,3,7,8-TetraCDD. However, social-emotional scores were decreased in the high PCDDs/Fs-TEQ group and the high 2,3,7,8-TetraCDD group compared with those with mild exposure, after adjusting for confounding factors. Cognitive scores in the mild, moderate, and high DDI groups were significantly higher than those in low DDI group, but there were no differences in cognitive scores among the three higher DDI groups. These results suggest that perinatal exposure to dioxins may affect social-emotional development of 1-year-old toddlers, without diminishing global neurodevelopmental function.
authors.affiliation: Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Viet Nam; Department of Public Health, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293, Japan.
authors.forename: Tai The
authors.initials: TT
authors.lastname: Pham
authors.affiliation: Department of Public Health, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293, Japan. Electronic address: ni-koei@kanazawa-med.ac.jp.
authors.forename: Muneko
authors.initials: M
authors.lastname: Nishijo
authors.affiliation: Department of Public Health, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293, Japan.
authors.forename: Anh Thi Nguyet
authors.initials: ATN
authors.lastname: Nguyen
authors.affiliation: Department of Public Health, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Ishikawa 920-0293, Japan.
authors.forename: Nghi Ngoc
authors.initials: NN
authors.lastname: Tran
authors.affiliation: Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Viet Nam.
authors.forename: Luong Van
authors.initials: LV
authors.lastname: Hoang
authors.affiliation: Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Viet Nam.
authors.forename: Anh Hai
authors.initials: AH
authors.lastname: Tran
authors.affiliation: Biomedical and Pharmaceutical Research Center, Vietnam Military Medical University, Ha Noi, Viet Nam.
authors.forename: Trung Viet
authors.initials: TV
authors.lastname: Nguyen
authors.affiliation: System Emotional Science, Graduate School of Medicine, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan.
authors.forename: Hisao
authors.initials: H
authors.lastname: Nishijo
mesh_terms: D001942:Breast Feeding / Q000706:statistics & numerical data; D004147:Dioxins / Q000378:metabolism* / Q000633:toxicity; D004785:Environmental Pollutants / Q000378:metabolism* / Q000633:toxicity; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D018811:Maternal Exposure / Q000706:statistics & numerical data*; D009420:Nervous System / Q000254:growth & development*; D014744:Vietnam
chemical_list: D004147:Dioxins; D004785:Environmental Pollutants
keywords: Dioxin; Neurodevelopment; Social emotional behavior; Toddler; Vietnam