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Iowa State University

Agriculture

2004

Biological and Process Engineering and Technology

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Estrogen Content Of Dairy And Swine Wastes, D. Raj Raman, Elizabeth L. Williams, Alice C. Layton, Robert T. Burns, James P. Easter, Adam S. Daugherty, Michael D. Mullen, Gary S. Sayler Jul 2004

Estrogen Content Of Dairy And Swine Wastes, D. Raj Raman, Elizabeth L. Williams, Alice C. Layton, Robert T. Burns, James P. Easter, Adam S. Daugherty, Michael D. Mullen, Gary S. Sayler

D. Raj Raman

Naturally occurring estrogens in animal wastes may cause negative environmental impacts, yet their abundance in animal waste treatment and storage structures is poorly documented. To better quantify estrogen concentra tions in animal wastes, multiple waste samples were collected from treatment and storage structures at dairy and swine facilities and analyzed for concentrations of 17β-estradiol (E2), estrone (E1), and 17α-estradiol by gas chromatography−mass spectroscopy and by enzyme linked immunosorbent assay (E2 only). Mass ratios of each estrogen to the macronutrients nitrogen, phosphorus, and potassium were also determined. Because manure application rates are typically macronutrient-based, estrogen to macronutrient ratios are proportional to …


Periodic Draining Reduces Mosquito Emergence From Free-Water Surface Constructed Wetlands, Catherine R. Mayhew, D. Raj Raman, Reid R. Gerhardt, Robert T. Burns, Mary Sue Younger Jan 2004

Periodic Draining Reduces Mosquito Emergence From Free-Water Surface Constructed Wetlands, Catherine R. Mayhew, D. Raj Raman, Reid R. Gerhardt, Robert T. Burns, Mary Sue Younger

D. Raj Raman

Both subsurface flow and free-water surface constructed wetland systems have been used for partial treatment of manure-laden wastewater from animal production systems. Subsurface flow systems are considerably more expensive but do not breed mosquitoes. The less expensive free-water surface systems have significant mosquito production potential, which is a serious drawback, especially because of increasing concerns about emerging mosquito-borne disease organisms. Periodically draining constructed wetlands has been suggested as a method of mosquito control. To test this approach, eight free-water surface constructed wetland mesocosms (0.7 m2 each) were operated on a one-week drain/fill cycle. Simultaneously, four subsurface flow mesocosms were operated …