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Sun X.L.,Kanazawa University | Kido T.,Kanazawa University | Okamoto R.,Kanazawa University | Manh H.D.,Kanazawa University | And 9 more authors.
Biomarkers | Year: 2014

A recent study found an inverse correlation between serum TCDD levels and serum testosterone in the US veterans, while there is little known on the dioxin and steroid hormones about Vietnamese men. We collected blood samples from 48 men who had resided in a hotspot when exposure happened and 38 men in a non-sprayed area. Some steroid hormones levels showed significant differences between two areas. There were no correlations between steroid hormones and dioxin TEQ, after ajusting for age and other factors. Our findings indicate that steroid hormones of Vietnamese men did not correlate with dioxin TEQ in two areas. © 2014 Informa UK Ltd. All rights reserved: reproduction in whole or part not permitted. Source

Manh H.D.,Kanazawa University | Manh H.D.,Lac Hong University | Kido T.,Kanazawa University | Tai P.T.,Vietnam Military Medical University | And 12 more authors.
Science of the Total Environment | Year: 2015

We determined polychlorinated dibenzodioxin (PCDD) and polychlorinated dibenzofuran (PCDF) levels in breast milk of 143 primiparae living around the three most dioxin-contaminated areas of Vietnam. The women sampled lived in the vicinity of former U.S. air bases at Bien Hoa (n. =. 51), Phu Cat (n. =. 23), and Da Nang (n. =. 69), which are known as dioxin hotspots. Breast milk samples from Bien Hoa City, where residents live very close to the air base, showed high levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), with 18% of the samples containing >. 5. pg. TCDD/g lipid. However, Phu Cat residents lived far from the air base and their samples showed lower TCDD levels, with none containing >. 5. pg. TCDD/g lipid. In Da Nang, TCDD levels in mothers from Thanh Khe (close to the air base, n. =. 43) were significantly higher than those in mothers from Son Tra (far from the air base, n. =. 26), but not other PCDD and PCDF (PCDD/F) congeners. Although TCDD levels in Bien Hoa were the highest among these hotspots, levels of other PCDD/F congeners as well as the geometric mean concentration of total PCDD/F level in Bien Hoa (9.3. pg toxic equivalents [TEQ]/g lipid) were significantly lower than the level observed in Phu Cat (14.1. pg. TEQ/g lipid), Thanh Khe (14.3. pg. TEQ/g lipid), and Son Tra (13.9. pg. TEQ/g lipid). Our findings indicated that residents living close to former U.S. air bases were exposed to elevated levels of TCDD, but not of other PCDD/F congeners. © 2014 Elsevier B.V. Source

Manh H.D.,Kanazawa University | Manh H.D.,Lac Hong University | Kido T.,Kanazawa University | Okamoto R.,Kanazawa University | And 13 more authors.
Environmental Health and Preventive Medicine | Year: 2013

Objective: Nearly 40 years after Agent Orange was last sprayed, we conducted a cross-sectional study to evaluate the impact of dioxin exposure on salivary hormones in Vietnamese primiparae. Our previous studies found higher levels of salivary cortisol and cortisone in one of the most highly dioxin-contaminated areas, known as a "hot-spot", than in a non-exposed area. As a result, we suggested that further research with a larger number of participants would be needed to confirm whether dioxin affects steroid hormone levels in Vietnamese primiparae. Methods: The concentration of steroid hormones in saliva was determined by liquid chromatography (electrospray ionization tandem mass spectrometry), whereas the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in breast milk were determined by gas chromatography-high resolution mass spectrometry, for a sample of the population from a "hot-spot" (n = 16) and a non-exposed area (n = 10). All subjects were aged between 20 and 30 years and had children aged between 4 and 16 weeks. Results: The mean toxic equivalence of PCDDs, PCDFs and PCDDs + PCDFs in breast milk in the hot-spot area was found to be significantly higher than in the non-exposed area (p < 0.001). Likewise, salivary cortisol, cortisone and dehydroepiandrosterone (DHEA) levels were significantly higher in the hotspot area than in the non-exposed area (p < 0.05). As a result, herein we report, for the first time, that salivary DHEA levels in primiparae are higher in a hot-spot than in a non-exposed area, and that this may be the result of dioxin exposure. Conclusions: Our findings highlight the long-term effects of Agent Orange/dioxin on steroid hormones in Vietnamese primiparae in the post-war period. © 2012 The Japanese Society for Hygiene. Source

Kido T.,Kanazawa University | Honma S.,Kanazawa University | Nhu D.D.,Vietnam National University, Hanoi | Manh H.D.,Kanazawa University | And 10 more authors.
Science of the Total Environment | Year: 2016

This study aims to evaluate the endocrine-disrupting effect of dioxin congeners on adrenal steroid hormones in mother-child pairs. In our previous study, we found that cortisol and cortisone levels were higher in the blood and the saliva of mothers living in a dioxin hotspot area than in mothers from a non-exposed region in Vietnam. In this follow-up study, we determined the salivary steroid hormone levels in 49 and 55 three-year-old children of these mothers in the hotspot and non-exposed region, respectively. Steroid hormones were determined by liquid chromatography-tandem mass spectrometry, and dioxin in the maternal breast milk was determined by gas chromatography-mass spectrometry. Dioxin levels in the breast milk of mothers from the hotspot (median total toxic equivalents polychlorinated dibenzodioxins/polychlorinated dibenzofurans; (TEQ PCDD/Fs) of 11. pg/g lipid) were three to four times higher than those of mothers in the non-exposed region (median TEQ PCDD/Fs of 3.07. pg/g lipid). Salivary dehydroepiandrosterone (DHEA) levels in children were found to be significantly lower in the hotspot than in the non-exposed region, while cortisol and cortisone levels were not different between the two regions. Highly chlorinated dioxin congeners, such as octacholorodibenzodioxin (OCDD), 1,2,3,4,6,7,8-heptacholorodibenzodioxin (HpCDD) and 1,2,3,4 (or 6), 7,8-hexachlorodibenzodioxin Hx(CDD), showed stronger inverse associations with the children's salivary DHEA than other lowly chlorinated dioxin congeners. Glucocorticoid levels in the mothers exhibited a significantly positive correlation with OCDD and HpCDD/F (polychlorinated dibenzofurans). In conclusion, highly chlorinated dioxin congeners are more strongly correlated with endocrine-disrupting effects on adrenal hormones, resulting in high cortisol levels in the mothers and low DHEA levels in their three-year-old children. © 2016 Elsevier B.V. Source

Sun X.,Kanazawa University | Kido T.,Kanazawa University | Okamoto R.,Kanazawa University | Manh H.D.,Kanazawa University | And 11 more authors.
Environmental Health and Preventive Medicine | Year: 2013

Objectives: The aim of this study was to explore the impact of Agent Orange exposure for prostate cancer with a comparison of the prostate specific antigen (PSA) levels between a hotspot and a non-sprayed area. Methods: The study was conducted in Phu Cat district (hotspot) and Kim Bang district (non-sprayed), with a total of 101 men in the hotspot and 97 men in the non-sprayed area older than 50 years of age. About 5 mL of whole blood and a health status questionnaire were collected from each subject in August 2009-2011. Results: The mean age of the subjects in the hotspot (68.0 years old) was significantly higher than that of those in the non-sprayed area (65.0 years old). No significant difference was found between the hotspot area (0.93 ng/mL) and the non-sprayed area (0.95 ng/mL) in terms of PSA levels. Likewise, this was not statistically significant after adjusting for age. The prevalence of high PSA levels (>3 ng/mL) did not differ significantly between the hotspot (14 men; 13.9 %) and non-sprayed area (9 men; 9.3 %). No significant difference was found between the hotspot area and the non-sprayed area in terms of occupation (farmer and others). In control subjects, no significant difference was found between the PSA levels in subjects exposed to Agent Orange and non-exposed subjects. Likewise, no significant difference was found between the PSA levels of combatants and civilians. Conclusion: The PSA levels were not significantly different between the hotspot and the non-sprayed area. © 2013 The Japanese Society for Hygiene. Source

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