Comparison of Three Extraction Methods for 17 β-Estradiol in Sand,Bentonite, and Organic-Rich Silt Loam

Extraction is an important procedure for samples that contain soil because other compounds in soil may affect analysis of estrogens. This study was conducted to evaluate three different extraction methods for 17β-estradiol in soil. Sand, bentonite, and organic-rich silt loam were spiked with 1 mg kg^{? 1} of 17β-estradiol as a model compound of estrogens. 17β-estradiol and its metabolites, estrone and estriol, were extracted using (i) a modified Bligh and Dyer extraction, (ii) a pressurized fluid extraction, and (iii) a diethyl ether extraction, and measured by liquid chromatography tandem mass spectrometry. There were significant differences in the extraction efficiency for 17β-estradiol among the extraction methods and the soils: the efficiencies ranged from 10% to 97%. Overall, the diethyl ether extraction method had the largest efficiency of 17β-estradiol with 45% and 57% for bentonite and silt loam, respectively. Transformation of 17β-estradiol to estrone and estriol in the different extraction methods was less than 3.6% during the extraction procedures. This study underlined the importance of sample preparation for estrogen analysis in soil samples.     

Effects of estrone on the early life stages and expression of vitellogenin and estrogen receptor genes of Japanese medaka (Oryzias latipes)

The fertilized eggs of Japanese medaka (Oryzias latipes) were exposed to estrone (E1) at 5–5000 ng L⁻¹ for 15 d, and the hatched fry were exposed continuously to the same concentrations for the additional 15 d. Adverse effects on hatchability, time to hatching, and gross abnormalities occurred at 50 ng L⁻¹ or above. Then the fry were divided into a continual exposure group, and a water recovery group. When the fry were exposed to E1 for another 60 d, there was a decrease in the hepatosomatic index (HSI) of males and the influence disappeared in the water recovery group. The gonadosonatic index (GSI) of females at 500 ng L⁻¹ decreased significantly in another 60 d exposure. While the fry were maintained in dechlorinated tap water for 60 d, a significant decrease in female GSI was observed at 50 ng L⁻¹ or above. An increased GSI was found in males in both continual exposure and water recovery groups at all E1 treatments. Quantitative RT-PCR showed that vitellogenin-I (Vtg-I) gene expressions in the female liver were significantly down-regulated at 50 ng L⁻¹ in the continual exposure group, and at 500 ng L⁻¹ in the water recovery group, while male Vtg-I genes were significantly up-regulated for all E1 treatments. In addition, all E1 treatments caused sex reversal of males. These results suggest that E1 at 5 ng L⁻¹ or above have unrecoverable impacts on the gonadal growth and development of medaka, even if only early life stages were exposed to E1.     

雌酮(E1)在土壤中的吸附特性

研究了平衡时间、温度、pH、离子强度和土壤粒径对E1(雌酮)在土壤中吸附特性的影响. 结果表明:E1在土壤中的等温吸附平衡时间约为0.5h;在温度为10、20和30℃条件下,土壤对E1的K_f(吸附系数)分别为24.72、14.18和9.39,K_d(分配系数)分别为34.79、24.15和13.51,表明随着温度的升高,土壤对E1的吸附量显著降低;土壤对E1的吸附量在pH由3.0增至6.0时呈降低趋势,在pH>6.0～9.0时保持稳定,然后随着pH进一步升高(>9.0～11.0)而继续降低;土壤对E1的吸附量在离子强度由0.005mol/L升至0.1mol/L时显著升高,在离子强度>0.1mol/L时保持稳定;砂粒、粉粒和黏粒对E1的K_f分别为5.17、12.79和25.22,K_d分别为6.80、16.11和39.95,即随着土壤粒径的减小,对于E1的吸附作用显著增加.      

Abiotic oxidation of 17β-estradiol by soil manganese oxides

The degradation of 17β-estradiol (E2) in sterile soil and Mn-free soil slurries was determined. In 0.075 g ml⁻¹ soil slurry, E2 with an initial concentration of 0.0267 μmol g⁻¹ was rapidly degraded and near equimolar estrone (E1) accumulated. A mass balance involving E2 and E1 existed throughout the reaction. The E2 degradation was thus an oxidation process and E1 was the only product. The concurrent release of Mn(II) during E2 oxidation and a lack of E2 oxidation in Mn-free soil slurry together demonstrated that soil manganese oxides were responsible for E2 oxidation. The degree of E2 oxidation was higher at high pH than at low pH, consistent with the fact that the reaction released protons. This study suggests that manganese oxides may be used as soil amendments to effectively oxidize E2 to less potent E1 in soil.     

Inter-laboratory exercise on steroid estrogens in aqueous samples

An inter-laboratory comparison exercise was organized among European laboratories, under the aegis of EU COST Action 636: “Xenobiotics in Urban Water Cycle”. The objective was to evaluate the performance of testing laboratories determining “Endocrine Disrupting Compounds” (EDC) in various aqueous matrices. As the main task three steroid estrogens: 17α-ethinylestradiol, 17β-estradiol and estrone were determined in four spiked aqueous matrices: tap water, river water and wastewater treatment plant influent and effluent using GC-MS and LC-MS/MS. Results were compared and discussed according to the analytical techniques applied, the accuracy and reproducibility of the analytical methods and the nature of the sample matrices. Overall, the results obtained in this inter-laboratory exercise reveal a high level of competence among the participating laboratories for the detection of steroid estrogens in water samples indicating that GC-MS as well as LC-MS/MS can equally be employed for the analysis of natural and synthetic hormones.     

Metabolic responses of Eisenia fetida after sub-lethal exposure to organic contaminants with different toxic modes of action

Nuclear magnetic resonance (NMR) - based metabolomics has the potential to identify toxic responses of contaminants within a mixture in contaminated soil. This study evaluated the metabolic response of Eisenia fetida after exposure to an array of organic compounds to determine whether contaminant-specific responses could be identified. The compounds investigated in contact tests included: two pesticides (carbaryl and chlorpyrifos), three pharmaceuticals (carbamazephine, estrone and caffeine), two persistent organohalogens (Aroclor 1254 and PBDE 209) and two industrial compounds (nonylphenol and dimethyl phthalate). Control and contaminant-exposed metabolic profiles were distinguished using principal component analysis and potential contaminant-specific biomarkers of exposure were found for several contaminants. These results suggest that NMR-based metabolomics offers considerable promise for differentiating between the different toxic modes of action (MOA) associated with sub-lethal toxicity to earthworms.     

UV-Vis/Fe(Ⅲ)/H2O2体系对水中雌酮的光降解

以250W照明金属卤化物灯为光源,研究了水中雌酮（E1）在UV-Vis／Fe（Ⅲ）／H2O2体系中的光降解;考查了初始pH、Fe（Ⅲ）、H2O2、E1初始浓度对E1光降解的影响。结果表明,UV-Vis／Fe（Ⅲ）／H2O2体系能有效地光降解E1,在[Fe（Ⅲ）30-20．8μmol／L、[H2O2]0=1664μmol／L、pH=3．0时,光照160min,18．5btmol／L E1的光降解率可达98．4%;在pH3．0～8．0范围内,pH初始值越小,E1降解率越大,反应初始速率越大;实验条件下,Fe（Ⅲ）、H2O2初始浓度越大,E1降解率越大,反应初始速率越大;E1初始浓度越低,E1降解率越大,反应初始速率越小。pH=3．0,实验浓度范围内的表观动力学方程为：dCE1／dt=0．00093[H2O2]^0.47[Fe（Ⅲ）]^0.62[E1]0.24;Fe（Ⅲ）是影响反应速率的主要浓度因素。