Effects of field-manure applications on stratified 17ß-estradiol concentrations.

The occurrence of the manure-borne estrogen, 17ß-estradiol (E2), was investigated in laboratory and field soils. In the laboratory, E2 was applied to soil to simulate concentrations found in swine (Sus scrofa domestica) manure (5000ngL(-1)). The aqueous-extracted E2 dissipated in the soil by 98% within 1h and was not significantly different from background concentrations (18ng L(-1)) for the duration of the experiment (64h). In the field study, soil cores were taken before and several dates after swine manure application. Equivalent porewater concentrations of water-extractable E2 were determined in 0.15-m increments down to the water table (0.70-2.00m deep). The average frequency of detection for 168 samples was 38% (average=40ng L(-1) porewater equivalents). Eleven days after manure application there was no significant effect on E2 detection frequency or concentration. However, E2 concentrations significantly increased by 6 months after manure application, and appeared to be related to precipitation. Concentrations then returned to original levels by 17 months after manure application. Manure did not have an immediate effect on E2 occurrence due to the capacity of the soil to rapidly sorb E2. However, it appears that soil may act as a long-term reservoir for E2 in the environment, which may be periodically released through desorption.

An on-farm survey of spatial and temporal stratifications of 17ß-estradiol concentrations.

17ß-estradiol (E2) is a natural estrogenic hormone found in animal manure and urine, which may cause endocrine disruption in sensitive organisms. 17ß-Estradiol has been widely detected in the environment, and animal agriculture may be an important source. The objectives of this study were to investigate the potential sources and/or spatial and temporal characteristics contributing to detections of E2 at the farm-scale. Soil cores, segmented into 0.15m increments, were taken down to the water table from four locations (three potential E2 sources and one control) at or around a swine (Sus scrofa domesticus) farm on five different dates between 2006 and 2007. Estradiol was quantified in the soil-water extracts using liquid chromatography-with tandem mass spectrometry (LC/MS/MS) analysis. Estradiol detections were widespread and found in 128 out of 345 extractions (37%). Concentrations ranged from 0 to 1910 ng L⁻¹ (porewater equivalents). A location that received field application of manure had significantly lower E2 concentrations compared to other locations. Also, the spring 2007 E2 concentrations were significantly higher than all other sample dates, perhaps related to climatic and hydrological events. Results suggested E2 was not directly related to manure sources, but was widespread in this environment. Where E2 was detected, highest concentrations favored the upper profile, while the greatest frequency of detections was in the lower profile and near the water table. Detections of E2 were associated with high organic mater contents in the upper profile and high sand contents in the lower profile. The study suggests that E2 is widespread in some soil environments, raising questions as to the source and mechanisms that facilitate its transport and mobility.