The State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, CAS, Wuhan, 430072, China.
Environ Sci Pollut Res Int. 2013 Jun;20(6):4268-77. doi: 10.1007/s11356-012-1447-2. Epub 2013 Jan 8.
In order to screen dioxin pollution in sediment of Three Gorges Dam (TGD) area, three sediment cores were obtained from two sites in 20102011; each core was divided into different samples with every 10 cm depth. Sediment dating determined by radiometry ((137)Cs, (210)Pb) and concentrations of dioxins were analyzed by high-resolution gas chromatography/mass spectrometry. The results indicated: Sediment dating showed no significant difference among all the samples from the same core and the two locations (ANOVA, p>0.05). The total amount of polychlorinated dibenzo-p-dioxins (PCDD)/Fs in all sample ranged from 30.7 to 371 pg/g dry weight (d.w.), with the mean value of 66.2 pg/g d.w. PCDDs occupied 60.3385.22 % of dioxins in each sample, and PCDFs contributed to a very small extend. There was no significant difference in the dioxin concentration between 2010 and 2011 and in the two locations (t test, p>0.05), but the vertical distribution of dioxins showed significant different in different depths. Toxic equivalent (TEQ) (WHO 2005, Humans) of samples ranged from 0.15 to 1.60 pg/g d.w.; the mean was 0.41 pg/g d.w. No significant difference was found in TEQ between 2010 and 2011(t test, p>0.05). It could be concluded that the distribution of dioxins showed the spatial heterogeneous which resulted from the strong mixing and sediment deposition characteristics. Dioxin concentration in sediment cores was low with very low environmental risk potential. Dioxins at the two sites had the same origin, and exogenous input was the main source. It is the first report on the dioxins concentrations in sediment cores in the TGD area.
为了筛查三峡库区沉积物中的二恶英污染，于 2010 年至 2011 年在两个地点采集了三个沉积物岩芯；每个岩芯均按 10cm 深度划分不同的样品。采用放射性测年法（（137）Cs、（210）Pb）和高分辨率气相色谱/质谱法分析了二恶英浓度。结果表明：同一岩芯和两个地点的所有样品的沉积年代没有显著差异（方差分析，p>0.05）。所有样品中二恶英总量（PCDD/Fs）范围为 30.7 至 371pg/g 干重（dw），平均值为 66.2pg/g dw。PCDDs 在每个样品中占二恶英的 60.33%至 85.22%，PCDFs 贡献很小。2010 年和 2011 年以及两个地点的二恶英浓度无显著差异（t 检验，p>0.05），但不同深度的二恶英垂直分布有显著差异。样品的毒性当量（TEQ）（2005 年世界卫生组织，人类）范围为 0.15 至 1.60pg/g dw；平均值为 0.41pg/g dw。2010 年和 2011 年的 TEQ 无显著差异（t 检验，p>0.05）。可以得出结论，二恶英的分布表现出空间异质性，这是由于强烈的混合和沉积特征造成的。沉积物岩芯中二恶英浓度较低，环境风险潜力较低。两个地点的二恶英具有相同的来源，外源输入是主要来源。这是关于三峡库区沉积物岩芯中二恶英浓度的首次报告。
