Partition of Endocrine-Disrupting Chemicals between Colloids and Dissolved Phase As Determined by Cross-Flow Ultrafiltration
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- 作者：Ruixia Liu ; Andrew Wilding ; Andrew Hibberd ; and John L. Zhou
- 刊名：Environmental Science & Technology
- 出版年：2005
- 出版时间：April 15, 2005
- 年：2005
- 卷：39
- 期：8
- 页码：2753 - 2761
- 全文大小：254K
- 年卷期：v.39,no.8(April 15, 2005)
- ISSN：1520-5851
文摘
Cross-flow ultrafiltration (CFUF) was developed first forthe isolation of natural colloids and subsequently fordetermining the partition of selected endocrine-disruptingchemicals (EDCs) between river colloids and dissolvedphase. In this study, a 1-kDa Millipore Pellicon 2 cartridgetype CFUF system was validated using a range of molecularprobes spiked in natural waters. Results show that goodretention (>80%) of high molecular weight (HMW, >1kDa) molecules and low retention of low molecular weight(LMW, <1 kDa) molecules can be achieved at highconcentration factor (cf) values in sampling mode or overlong time scales in recirculation mode. The interactionsbetween aquatic colloids and EDCs were studied by mixingEDCs, water, and colloids previously isolated by CFUFfor a certain duration, followed by the separation of thetarget compounds between the truly dissolved and colloid-bound phases by CFUF and analysis by gas chromatography-mass spectrometry (GC-MS). The kinetics of EDCsbinding to colloids were relatively rapid, reaching equilibriumwithin 5 min. The mass balance of chosen EDCs throughCFUF system was fully investigated, with good recovery forthe relatively polar EDCs such as estrone and 17
-estradiol. On the basis of EDC sorption by colloids, thepartition coefficient normalized to colloidal organic carboncontent (Kcoc) was 8.85 × 103, 1.50 × 104, 8.85 × 103,4.87 × 104, and 1.59 × 104 mL/g for bisphenol A, estrone, 17-estradiol, 17
-ethynylestradiol, and 16-hydroxyestrone,respectively, which are comparable with the values reportedin the literature. In addition, it has been shown that theKcoc values of EDCs were relatively independent of theiroctanol-water partition coefficient (Kow) values, suggestingthe important role of different binding mechanisms otherthan nonspecific hydrophobic interaction between EDCs andnatural colloids. As the CFUF-GC-MS method can beused to quantify very low concentration of pollutants andis not limited to fluorescent compounds, it has thepotential to be a widely applicable separation/analyticaltool for determining the partition of organic pollutants betweencolloidal materials and dissolved phase.
-estradiol. On the basis of EDC sorption by colloids, thepartition coefficient normalized to colloidal organic carboncontent (Kcoc) was 8.85 × 103, 1.50 × 104, 8.85 × 103,4.87 × 104, and 1.59 × 104 mL/g for bisphenol A, estrone, 17-estradiol, 17-ethynylestradiol, and 16-hydroxyestrone,respectively, which are comparable with the values reportedin the literature. In addition, it has been shown that theKcoc values of EDCs were relatively independent of theiroctanol-water partition coefficient (Kow) values, suggestingthe important role of different binding mechanisms otherthan nonspecific hydrophobic interaction between EDCs andnatural colloids. As the CFUF-GC-MS method can beused to quantify very low concentration of pollutants andis not limited to fluorescent compounds, it has thepotential to be a widely applicable separation/analyticaltool for determining the partition of organic pollutants betweencolloidal materials and dissolved phase.