Sorption of 17ß-Estradiol (E2) by Swine Manure Fractions.

Endocrine-disrupting chemicals (EDCs) in animal manures are potent contaminants that may enter water bodies through runoff from concentrated animal feeding operations or from manure-amended fields. Numerous studies have considered the distribution of EDCs like 17ß-estradiol (E2) between solid and liquid phases in soils. However, there is limited information about how the organic components of manure can adsorb EDCs and thus regulate their release to soil organic matter, soil clay particles, or water. Therefore, we undertook this investigation of the sorptive capacities of discrete manure components. Using a XAD-based fractionation scheme similar to that of Leenheer, we separated the < 75 µm components of bulk swine manure into fine particulate and colloidal fractions and into hydrophilic and hydrophobic fractions. Each fraction was contained in a dialysis bag and equilibrated with varying levels of E2 of up to 2 mg per L for 24 h.