title: Prenatal exposure to PCDDs/PCDFs and dioxin-like PCBs in relation to birth weight.
abstract: Several human studies have shown that low-level exposure to environmental contaminants, such as polychlorinated biphenyls (PCBs) and organochlorine pesticides, negatively influences birth outcomes. However, the effects of low-level exposure to polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like PCBs (DL-PCBs) on birth outcomes have not been clarified in human studies. A prospective cohort study was established to investigate the possible adverse effects of PCDDs/PCDFs and DL-PCBs on fetal growth and neurodevelopment. We recruited 514 pregnant women between July 2002 and October 2005 in Sapporo, Japan. We measured 29 congener levels of PCDDs/PCDFs and DL-PCBs in maternal blood. Using multiple liner regression analysis of the association between birth weight and the levels of PCDDs/PCDFs and DL-PCBs with full adjustments for potential confounders, a significant adverse effect was observed regarding total PCDDs toxic equivalents (TEQ) levels (adjusted beta=-231.5g, 95% CI: -417.4 to -45.6) and total PCDFs TEQ levels (adjusted beta=-258.8g, 95% CI: -445.7 to -71.8). Among male infants, significant adverse associations with birth weight were found for total PCDDs TEQ level, total PCDDs/PCDFs TEQ level, and total TEQ level. However, among female infants, these significant adverse associations were not found. With regard to individual congeners of PCDDs/PCDFs and DL-PCBs, we found significantly negative association with the levels of 2,3,4,7,8-PeCDF (adjusted beta=-24.5g, 95% CI: -387.4 to -61.5). Our findings suggest that prenatal low-level exposure to PCDDs and PCDFs, especially 2,3,4,7,8-PeCDF, may accumulate in the placenta and retard important placental functions, which result in lower birth weight.
authors.affiliation: Department of Public Health Sciences, Hokkaido University Graduate School of Medicine, North 15-West7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Kanae
authors.initials: K
authors.lastname: Konishi
authors.forename: Seiko
authors.initials: S
authors.lastname: Sasaki
authors.forename: Shizue
authors.initials: S
authors.lastname: Kato
authors.forename: Susumu
authors.initials: S
authors.lastname: Ban
authors.forename: Noriaki
authors.initials: N
authors.lastname: Washino
authors.forename: Jumboku
authors.initials: J
authors.lastname: Kajiwara
authors.forename: Takashi
authors.initials: T
authors.lastname: Todaka
authors.forename: Hironori
authors.initials: H
authors.lastname: Hirakawa
authors.forename: Tsuguhide
authors.initials: T
authors.lastname: Hori
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yasutake
authors.forename: Reiko
authors.initials: R
authors.lastname: Kishi
mesh_terms: D000293:Adolescent; D000328:Adult; D001572:Benzofurans / Q000506:poisoning*; D001724:Birth Weight / Q000187:drug effects*; D015331:Cohort Studies; D000072338:Dibenzofurans, Polychlorinated; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007564:Japan; D016014:Linear Models; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D011078:Polychlorinated Biphenyls / Q000506:poisoning*; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000506:poisoning; D011247:Pregnancy; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls