Residual congener pattern of dioxins in human breast milk in southern Vietnam

This study evaluated residual congener patterns of dioxin/furan (=PCDD/DF) related to tactical herbicides aerially sprayed over the regions of southern Vietnam through Operation Ranch Hand. The study focused on Cam Chinh (CC) commune, Quang Tri province (an area sprayed with tactical herbicides), and the Cam Phuc (CP) commune, Ha Tinh province (a non-sprayed area). Breast milk samples for analysis were collected in September 2002 and July 2003 from lactating primiparous and multiparous mothers born after the war (<31 years old). We found the levels of each congener in the CC commune were higher than in the CP commune, and determined specificity in the PCDD/DF congener pattern in CC commune samples by cluster analysis. The congener pattern is characterized by higher (the hexa-, the hepta-, and the octa-) chlorinated PCDD/DFs; this appears to be the same profile as that presented by pentachlorophenol (PCP), rather than 2,4,5-trichlorophenoxy acid (2,4,5-T) contaminated with 2,3,7,8-TCDD. A GC/MS study in the 1970s detected the chlorophenols 2,4-di and 2,4,6-trichlorophenol in some Agent Orange samples, which contained, like PCP, a wide variety of PCDD/DF congeners. In this context, it may be expected that certain tactical herbicides contaminated with various chlorophenol impurities, have a unique congener pattern when compared with pure 2,4,5-T formulations. © 2011 Elsevier Ltd. All rights reserved

ベトナムダイオキシン高濃度汚染地域における授乳中の母親の唾液中ホルモン値の検討

【目的】アメリカ軍は１９６１年から１９７１年の間に８０００万リットル以上の枯葉剤を南ベトナムに撒布した。この研究の目的はベトナムの枯葉剤高濃度汚染地域（Binh Dinh省Phu Cat県）と非汚染地域（Ha Nam省Kim Bang県）において枯葉剤（オレンジ剤）の暴露と人体への健康影響との関連を検討することである。【方法】２つの地域において疫学的調査を実施した。対象者は授乳中で生後４週から１６週の乳児を持つ２０－３０歳の母親とし、汚染地域では５８名、非汚染地域では５３名であった。疾患の危険因子等に関する情報は母親への面接調査から得た。母乳をすべての対象者から採取したが、唾液を採取したのは汚染地域４１名、非汚染地域１９名であった。母親と子どもの身体計測を行い２地域間で比較を行った。【結果と考察】汚染地域における乳児の体重と胸囲は有意に非汚染地域よりも小さいが、年齢(週数)も汚染地域の方が有意に低かった。汚染地域における母親とその家族の現病歴は非汚染地域よりも有意に多かった。母親の視力は両眼とも２地域間で有意差は認められなかった。汚染地域と非汚染地域双方の母親の唾液中のコルチゾン値は、母乳中のコルチゾン値と高い相関を示した。汚染地域と非汚染地域間で唾液中のホルモン値には有意差は認められなかった。Objective : Between 1961 and 1971 the US military used over 80 million litres of herbicides in southern Vietnam. This study aims to assess hormone levels in the saliva of lactating Vietnamese mothers and human health effects in a dioxin hot spot (Phu Cat district, Binh Dinh province) and a non-exposed (Kim Bang district, Ha Nam province) area in Vietnam. Materials and Methods : An epidemiological study was carried out in both areas. The subjects were 58 lactating females in the hot spot area and 53 lactating females in the non-exposed area. All were aged between 20 and 30 years with infants aged between 4 and 16 weeks. Information about disease risk factors was obtained through interviews with mothers. Breastmilk samples were taken from all subjects, whereas saliva samples were obtained from 41 mothers in the hot spot area and 19 in the non-exposed area. Body measurements for both mothers and their infants were compared between the two areas. Result and Discussion : The weight and chest circumference of infants in the hot spot area were significantly lower than those in the non-exposed area, whereas age (weeks) is also significantly younger in hot spot area than non-exposed area. Present maternal and family diseases in the hot spot area were significantly higher than those in the non-exposed area. Maternal eyesight in both eyes did not differ significantly between the two areas. The cortisone levels in saliva have been found to be closely related to those in breast milk samples of both mothers in hot spot and non-exposed areas. No significant difference was found between salivary hormone levels of mothers in the hot spot and non-exposed areas

High cortisol and cortisone levels are associated with breast milk dioxin concentrations in Vietnamese women

Objective: Dioxin (polychlorinated dibenzodioxins Cpolychlorinated dibenzofurans) is one of the most toxic chemical substances known. Although it is suspected to cause endocrine disruption, very few epidemiological studies have been carried out on its effects on human steroid hormones. The aim of this study was to elucidate the association of dioxin exposure with steroid hormone levels in the saliva and serum of Vietnamese women. Study design : Two areas, namely Phu Cat (hot spot) and Kim Bang (nonexposed area), were selected for the study. The study subjects consisted of 51 and 58 women respectively. Saliva, blood, and breast milk samples were collected from the subjects in both the areas. Methods: Cortisol, cortisone, DHEA, androstenedione, estrone, and estradiol levels in serum and saliva were determined by liquid chromatography-tandem mass spectrometry; dioxin concentrations in breast milk were measured by gas chromatography-mass spectrometry. Results: Dioxin concentrations in the breast milk of women from the dioxin hot spot were three to four times higher than those in the breast milk of women from the nonexposed area. Good correlations were found between the levels of six steroid hormones in saliva and those in serum respectively. Salivary and serum cortisol and cortisone levels in women from the dioxin hot spot were significantly higher than those in women from the nonexposed area (P<0.001) and those in all the subjects were positively associated with dioxin concentrations in Vietnamese women (P<0.01). Conclusion: These results suggest that dioxin influences steroidogenesis in humans. Saliva samples can be used for hormone analysis and are therefore excellent specimens in epidemiological studies. © 2014 European Society of Endocrinology

極域細菌のゲノム進化

第6回極域科学シンポジウム分野横断セッション：[IB2] 地球環境変動の解析と地球生命システム学の構築11月19日（木）　統計数理研究所 セミナー室1（D305