Prenatal exposure to PCDDs/PCDFs and dioxin-like PCBs in relation to birth weight

• Published in: Environmental research 2009-10, Vol.109 (7), p.906-913
• Main Authors: Konishi, Kanae, Sasaki, Seiko, Kato, Shizue, Ban, Susumu, Washino, Noriaki, Kajiwara, Jumboku, Todaka, Takashi, Hirakawa, Hironori, Hori, Tsuguhide, Yasutake, Daisuke, Kishi, Reiko
• Format: Article
• Language: English
• Subjects: Adjustment; Adolescent; Adult; Benzofurans - poisoning; Biological and medical sciences; Birth; Birth weight; Birth Weight - drug effects; Cohort Studies; Congeners; Contaminants; Dibenzofurans, Polychlorinated; Dioxin; Environmental pollutants toxicology; Female; Fetal growth; General aspects; Human; Humans; Infant, Newborn; Infants; Japan; Linear Models; Male; Maternal blood; Maternal Exposure - adverse effects; Medical sciences; Polychlorinated Biphenyls - poisoning; Polychlorinated Dibenzodioxins - analogs & derivatives; Polychlorinated Dibenzodioxins - poisoning; Pregnancy; Prenatal exposure; Prospective Studies; Regression analysis; Toxic; Toxicology; Young Adult
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2009.07.010

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 β=−231.5 g, 95% CI: −417.4 to −45.6) and total PCDFs TEQ levels (adjusted β=−258.8 g, 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 β=−24.5 g, 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.