| This paper studies the new analytical techniques for the determination of steroid hormones in water sample from the Sewage Treatment Plant (STP), which is focused on the new extraction procedures and new instrumental hyphenated techniques. It mainly consists of the following six parts.In the first part, the definition of Endocrine disrupting compounds (EDC) and the most potent EDC categories --steroid hormones and their analytical techniques, environmental fate were introduced based on 110 previous references.In the second part, a method based on cloud point extraction was developed to determine estrogens (estrone, estradiol, estriol, and progesterone) in environmental water samples by high-performance liquid chromatography separation and ultraviolet detection (HPLC-UV). The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, preconcentration factors of 99, 73, 152, 86 and detection of limits of 0.23, 0.32, 0.25, 5.0 ng/mL for E3, E2, E1, P were obtained for 10-ml water sample. The proposed method was successfully applied to the determination of trace amount of estrogens in effluent water of the wastewater treatment plant (WWTP).In the third part, based on the method for extraction of estrogens by cloud point extraction, a method was developed to determine phthalate esters (di-ethyl-phthalate, di-(2-ethylhexyl)-phthalate and di-cyclohexyl-phthalate) in environmental water samples by high-performance liquid chromatography separation and ultraviolet detection (HPLC-UV). The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, preconcentration factors of 35, 88, 111 and detection of limits of 2.0, 3.8, 1.0 ng.ml-1 were obtained for DEP, DEHP and DCP in 10-ml water sample. The proposed method was successfully applied to the determination of trace amount of phathalate esters in effluent water of the wastewater treatment plant (WWTP) and the lixivium of plastic fragments.In the fourth part, a new method for the determination of four estrogens, estriol, 17β-estradiol, 17α-ethynyl-estrodiol and estrone in water was established. The method involves solid-phase extraction of water samples and subsequent analysis of the extract by ultra-performance liquid chromatography (UPLC) coupled with an ultraviolet detector (UVD). Baseline separation was achieved for all the studied estrogens using a column (50×2.1mm) packed with 1.7 urn particle size stationary phase. The recoveries (>90%), detection limits (12.5-23.7 ng/L) and RSDs (7-11%) for the four estrogens were all satisfactory. The proposed method was successfully applied in determining the decrease of E2 and EE2 in simulative natural water. It was found that within 48 hours, the concentration of E2 decreased to 30% of its initial level (with a half-life of about 30 h), whereas EE2 decreased to 45% of its initial level (with a half-life of about 36 h). Low levels of E1 were found, while E3 was undetectable during the process.In the fifth part, concentrations of natural and synthetic estrogens (estriol, 17β-estradiol, 17α-ethynyl-estrodiol, estrone, 17α-hydroxyprogesterone and progesterone) and androgens (testosterone, epitestosterone, methyltestosterone, 4-androstene-3, 17-dione) in the influent and effluent of the Gaobeidian sewage treatment plant (Beijing, China) and along the receiving river, the Tonghuihe River were determined by HPLC-MS-MS. The samples were collected during six months, so the seasonal variations of steroids were studied in the river. Estrone, estriol and testosterone were the dominant compounds (detected in all effluent samples), while estradiol, 17α-ethynylestradiol and 4-androstene-3, 17-dione were detected in two samples, and progesterone wasn't detected in all the effluent and receiving water samples. The recoveries of the analytes ranged from 73% to 91%, and the limits of quantification were in the range of 0.1-1 ng/L. The results indicated that the concentrations of steroids in winter were obviously higher than those in summer, which might be caused by temperature as the major factor in biodegradation process.In the sixth part, a sensitive and automated method was presented for the determination of four estrogens (El, E2, E3, EE2) in wastewater by GC-MS equipped with a programmable temperature vaporizer (PTV-LV) injection port. N-O-bis-(trimethylsilyl)-trifluoroacetamide in pyridine containing 1% trimethylchlorosilane was chosen as derivatization reagent. The PTV-LV injection settings used herein could greatly improve the sensitivity of the analytical method. The proposed method offered detection limits ranging from 0.1 ng/L to 0.33 ng/L for four tested compounds, which was about 10 to 50 times more sensitive than the results achieved by the conventional 1μl splitless injection. The improved method was successfully applied to the analysis of estrogens in the wastewater, the result was proved by HPLC-MS-MS.
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