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Estrogenic Compounds in Wastewater Presentation to the Metropolitan Council Environment Committee September 23, 2008. Paige Novak, Deb Swackhamer, Mike Semmens, Megan Ogdahl, Matt Wogen, Mark Lundgren University of Minnesota. What is the problem?.
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Estrogenic Compounds in Wastewater Presentation to the Metropolitan Council Environment Committee September 23, 2008 Paige Novak, Deb Swackhamer, Mike Semmens, Megan Ogdahl, Matt Wogen, Mark Lundgren University of Minnesota
What is the problem? • Endocrine disruptors, estrogenic compounds, and other pharmaceuticals have been observed in streams and wastewater treatment plant discharges throughout the United States, Europe, and Asia e.g., Jobling et al., 1998; Ternes et al., 1999; Holbrook et al., 2002; Kolpin et al., 2002; Joss et al., 2004; Pojana et al., 2004
Hormones • Chemical signals pass through the blood and bind to cells in the target organ; initiates physiochemical response • Crucial for reproductive function and development Natural hormone Receptor Physiochemical response Target cell Secreting cell
Hormones • Chemical signals pass through the blood and bind to cells in the target organ; initiates physiochemical response • Crucial for reproductive function and development External chemical Receptor Physiochemical response Target cell Secreting cell
Hormones • Chemical signals pass through the blood and bind to cells in the target organ; initiates physiochemical response • Crucial for reproductive function and development External hormone or estrogen mimic Receptor Unintended Physiochemical response Target cell
Research question: How do estrogens or estrogen mimics behave across a wastewater treatment plant? If we have a body of data we are better able to gauge risk, know which compounds are problematic, how to monitor them, better treat the material, etc.
What we analyze • Binding assays: total sample “estrogenicity” (including unknown compounds) • Analytical (LC-MS): specific compounds only • Phytoestrogens • Genistein • Industrial compounds (+breakdown products) • Nonylphenol • Octylphenol • Bisphenol A • Antimicrobial • Triclosan • Synthetic or natural estrogenic hormones • Estradiol • Estrone • Ethynylestradiol • Estriol
Methods for analysis Collect samples Incubate with samples and quantify binding Specific compounds quantified (40 L concentrated to 150-300 uL) Processing & cleanup receptors Cells (yeast or trout liver) Sample processing Yeast cells: alive, human estrogen receptor Trout liver cells: not “alive,” trout estrogen receptor
Sample locations Seasonal chlorination Primary treatment Settling Secondary treatment Screens, grit removal, and primary settling Activated sludge Recycle streams Recycle activated sludge Primary sludge Solids processing Centrifugation Blended thickened sludge Centrate Biosolids
Total “estrogenicity” Not Chlorinating Chlorinating Not Chlorinating Chlorinating Chlorinating
Total “estrogenicity” • Overall the influent and effluent estrogenicity data were consistent with time • Removal occurs across the activated sludge tank
Specific compounds • Some compounds are removed effectively and are present in low concentrations in the effluent (e.g., Bisphenol A)
Specific compounds • Other compounds appear to recycle internally and removals vary (e.g., nonylphenol)
Specific compounds • Interpretation of estrone data is complicated since it can be formed through the oxidation of estradiol conjugates and subsequently transformed
Specific compounds • Occasionally highly estrogenic compounds such as estriol and ethynylestradiol were detected in the effluent • Estriol: 7/2006, 410 ng/L • 11/2006, 0 ng/L • 5/2007, 0 ng/L • 7/2007, 0 ng/L • Ethynylestradiol: 7/2006, 0 ng/L • 11/2006, 0 ng/L • 5/2007, 18 ng/L • 7/2007, 0 ng/L
Summary of results & conclusions • Influent estrogenicity does not vary significantly at the Metro Plant • Estrogenic compounds are treated; the effluent appears to contain primarily nonylphenol, bisphenol A, and estrone (solids contain nonylphenol, bisphenol A, and triclosan) • Binding assays have utility but you have to use them carefully
What we don’t know • How do we optimize removal under standard plant conditions in a cost-effective way? • How do plant conditions change on a weekly/daily basis and how does this change removal? • What other compounds are in the solids? Are they stable? How are they best treated (other than at Metro…)? • What other compounds are present that could be problematic (Sertraline, other pharmaceuticals)?
On-going and future work • Investigating the presence, effect, and transformation of estrogens in septic discharges (N shore of Lake Superior) • Investigating the presence and transformation of phytoestrogens in industrial wastewaters
Currently proposed work • Proposed investigation of BPA, NP, estrone, triclosan, and triclocarban transformation under realistic conditions • Proposed investigation to determine how to stop the use of non-necessary endocrine disruptors
Other possible projects/questions • Investigate other compounds (particularly pharmaceuticals) • Pilot-scale studies • Investigate solids (what compounds are present, how mobile are they, how should they be treated?)
Future partnership? • We have the ability to help the MCES address long-range, larger-scale challenges and mitigate future risk • The University has: • Highly-trained, cost-effective labor and expertise (graduate students and faculty) • Exceptional research facilities
Acknowledgements • Students: Megan Ogdahl, Matt Wogen, Mark Lundgren • Collaborators: Mike Semmens, Deb Swackhamer • WWTP Staff (Metropolitan Plant, St. Paul, WLSSD Plant, Duluth) • Funding: Legislative-Citizen Commission on Minnesota Resources • Other research: Paul L. Busch Award (Water Environment Research Foundation), EPA GLNPO, DC Water and Sewer Authority, Heiko Schoenfuss, Bill Arnold, David Fulton