Engineering Commons^™

Fate And Transport Of Pathogen Indicators From Pasturelands, Michelle L. Soupir

Michelle L. Soupir

The U.S. EPA has identified pathogen indicators as a leading cause of impairments in rivers and streams in the U.S. Elevated levels of bacteria in streams draining the agricultural watersheds cause concern because they indicate the potential presence of pathogenic organisms. Limited understanding of how bacteria survive in the environment and are released from fecal matter and transported along overland flow pathways results in high uncertainty in the design and selection of appropriate best management practices (BMPs) and in the bacterial fate and transport models used to identify sources of pathogens.

The overall goal of this study was to improve …

Degradation Of Estrogens In Dairy Waste Solids: Effects Of Acidification And Temperature, D. Raj Raman, Alice C. Layton, Lara B. Moody, James P. Easter, Gary S. Sayler, Robert T. Burns

D. Raj Raman

Manure–borne estrogens are increasingly recognized as a potential ecological hazard. However, sample–handling protocols for these compounds are not clearly delineated in the literature, nor are comparisons between assays for estrogens. A study was conducted to explore the degradation of estrogen in separated dairy manure waste solids (press cake), using three popular assay types. Estrogens were measured by enzyme–linked immunosorbent assay (ELISA), gas–chromatography mass–spectroscopy (GC–MS) and a recombinant yeast estrogen reporter assay. As measured by GC–MS, background estrone concentrations were approximately 100 ppb, while 17β–estradiol concentrations were one–third of the estrone concentration, and 17β–estradiol concentrations were below the detection limit (10 …