title: Effects of in utero exposure to polychlorinated biphenyls, methylmercury, and polyunsaturated fatty acids on birth size.
abstract: The adverse effects of in utero exposure to polychlorinated biphenyls (PCBs) or methylmercury (MeHg), and the beneficial effects of nutrients from maternal fish intake might have opposing influences on fetal growth. In this study, we assessed the effects of in utero exposure to PCBs and MeHg on birth size in the Japanese population, which is known to have a high frequency of fish consumption. The concentrations of PCBs and polyunsaturated fatty acids in maternal blood, and the total mercury in hair (as a biomarker of MeHg exposure) were measured during pregnancy and at delivery. Maternal intakes of fish (subtypes: fatty and lean) and shellfishes were calculated from a food frequency questionnaire administered at delivery. Newborn anthropometric measurement data were obtained from birth records. The associations between chemical exposures and birth size were analyzed by using multiple regression analysis with adjustment for confounding factors among 367 mother-newborn pairs. The birth weight was 3073±37 g (mean±SD). The incidence of babies small for gestational age (SGA) by weight was 4.9%. The median concentrations of total PCBs and hair mercury were 108 ng/g lipid and 1.41 μg/g, respectively. There was no overall association between mercury concentrations and birth weight, birth length, chest circumference, and head circumference. We observed that the risk of SGA by weight decreased with increasing mercury concentration in regression analyses with adjustment for polyunsaturated fatty acids. Our results suggest that the beneficial effect of essential nutrition may mask the adverse effects of MeHg on birth size. The concentrations of PCBs had no association with birth size.
authors.affiliation: Center for Environmental and Health Sciences, Hokkaido University, North 12 West 7 Kita-ku, Sapporo 060-0812, Japan.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Miyashita
authors.affiliation: Department of Public Health Sciences, Hokkaido University Graduate School of Medicine, North 15 West 7 Kita-ku, Sapporo 060-8638, Japan.
authors.forename: Seiko
authors.initials: S
authors.lastname: Sasaki
authors.affiliation: Center for Environmental and Health Sciences, Hokkaido University, North 12 West 7 Kita-ku, Sapporo 060-0812, Japan.
authors.forename: Tamiko
authors.initials: T
authors.lastname: Ikeno
authors.affiliation: Center for Environmental and Health Sciences, Hokkaido University, North 12 West 7 Kita-ku, Sapporo 060-0812, Japan.
authors.forename: Atsuko
authors.initials: A
authors.lastname: Araki
authors.affiliation: Center for Environmental and Health Sciences, Hokkaido University, North 12 West 7 Kita-ku, Sapporo 060-0812, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Ito
authors.affiliation: Fukuoka Institute of Health and Environmental Sciences, Mukaizano 39, Dazaifu 818-0135, Japan.
authors.forename: Jumboku
authors.initials: J
authors.lastname: Kajiwara
authors.affiliation: Kitakyushu Life Science Center, Public Interest Incorporated Foundation, 1-4 Nakabarushinmachi Tobata-ku Kitakyushu-shi, Fukuoka 804-0003, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Todaka
authors.affiliation: Department of Epidemiology, National Institute for Minamata Disease, 4058-18 Hama, Kumamoto 867-0008, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Hachiya
authors.affiliation: Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Yasutake
authors.affiliation: Department of Environmental Health Sciences, Akita University, Graduate School of Medicine, Akita 010-8543, Japan.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Murata
authors.affiliation: Department of Occupational and Environmental Health, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
authors.forename: Tamie
authors.initials: T
authors.lastname: Nakajima
authors.affiliation: Center for Environmental and Health Sciences, Hokkaido University, North 12 West 7 Kita-ku, Sapporo 060-0812, Japan. Electronic address: rkishi@med.hokudai.ac.jp.
authors.forename: Reiko
authors.initials: R
authors.lastname: Kishi
mesh_terms: D001724:Birth Weight; D002681:China; D004785:Environmental Pollutants / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D005260:Female; D047109:Fetal Development; D005506:Food Contamination / Q000706:statistics & numerical data; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D018811:Maternal Exposure / Q000706:statistics & numerical data*; D008767:Methylmercury Compounds / Q000378:metabolism*; D011078:Polychlorinated Biphenyls / Q000378:metabolism*; D011247:Pregnancy
chemical_list: D004785:Environmental Pollutants; D005231:Fatty Acids, Unsaturated; D008767:Methylmercury Compounds; D011078:Polychlorinated Biphenyls; C004925:methylmercuric chloride
keywords: Birth size; In utero exposure; Methylmercury; Polychlorinated biphenyls; Polyunsaturated fatty acids; Small for gestational age