Occurrence and Fate of Hormones in the Stroubles Creek Watershed.

Hormones are contaminants of emerging concern and are often sourced from the agricultural industry.   Hormones are endocrine disrupting compounds that can be detrimental to the sexual development of aquatic organisms, causing population losses and deformities. Manure amendments to agricultural fields concurrently apply steroid hormones with beneficial plant nutrients. These hormones are introduced to natural environments surrounding manure applied fields by runoff.   When hormones are degraded in the environment, they are often transformed into metabolites that can still cause environmental impacts, therefore it is important to simultaneously detect hormone parent compounds as well as their metabolites.   In this study the occurrence of 11 hormones, hormone precursors, and conjugated hormones were investigated in soils from an animal manure-applied field adjacent to the Stroubles Creek in Blacksburg, VA.  Soil samples from 0-5cm and 5-20cm were collected from 20 points along the drainage swales of the manure applied field at time intervals following manure application.  The concentration of hormones in the Stroubles Creek stream water and bed sediments was also determined.   The target compounds were extracted from the soil and sediment samples using high pressure solvent extraction followed by cleaning up using solid phase extraction.  The target compounds in the water samples were extracted and cleaned up using solid phase extraction.  The soil and water extracts were analyzed by LC/MS/MS. Preliminary results show that 6 months after the application of manure, progesterone was the only detected hormone in the soil of both depths.  Higher progesterone concentrations were detected in the 0-5 cm soils of drainage swales compared to the soils from the ridges, indicating surface runoff. The highest progesterone levels were detected in both soil depths from the riparian buffer zone separating the animal applied field and the stream, suggesting possible surface runoff of progesterone to the buffer zone with subsequent leaching in the water saturated buffer zone. The results suggested that progesterone is more persistent than other hormones in the soils and it is more susceptible to runoff and leaching.