Vertical Transport of Hormones in Effluent-Irrigated Cropland.

The negative health effects of endocrine-disrupting compounds demand a greater understanding of their potential to contaminate groundwater from land application of byproducts and effluents.  Over a 3-month period, we investigated the leaching of secondary effluent spiked with 17 β-estradiol (E2), estrone (E1), 17 α-ethynlestradiol (EE2), and a bromide (Br) tracer through undisturbed cubic soil lysimeters (61 cm on a side) cut from areas containing Hagerstown silt loam and Morrison sandy loam soils. The Br tracer emerged from the lysimeters after only ~0.1 pore volumes of effluent had been leached, indicating the presence of preferential flow paths that potentially enhance downward migration of solutes. The leachate estrogen concentrations were generally <10% of the applied levels, suggesting retention and or degradation by the soils. The HYDRUS 1D model was used to estimate the transport parameters of the hormones.