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17β-estradiol and testosterone are naturally occurring steroids that co-occur in poultry litter. The effects of litter on sorption of these hormones to soil are not known. Sorption isotherms were developed for ^sup 14^C-labeled testosterone and ^sup 3^H-labeled estradiol in a Cecil sandy clay loam with and without poultry litter addition. The effect of applying the hormones alone (single-sorbate) or together (multisorbate) was also investigated. ^sup 14^C-testosterone sorption in soil increased from 2 to 48 h and remained relatively constant thereafter. ^sup 3^H-estradiol sorption in soil was relatively constant from 2 to 24 h and then decreased to 72 h. These differences may reflect transformation of the parent hormones to products with different solid-phase affinity. The maximum sorption coefficient (K^sub d^) in soil for ^sup 14^C-testosterone (20.2 mL g^sup -1^) was similar to that for ^sup 3^H-estradiol (19.6 mL g^sup -1^) in single-sorbate experiments. When hormones were applied together, sorption of both hormones in soil decreased, but the ^sup 14^C-testosterone K^sub d^ (12.5 mL g^sup -1^) was nearly twice as large as the ^sup 3^H-estradiol Kd (7.4 mL g^sup -1^). We propose this resulted from competition between the hormones and their transformation products for sorption sites, with ^sup 14^C-testosterone and its expected transformation product (androstenedione) being better competitors than ^sup 3^H-estradiol and its expected transformation product (estrone). When poultry litter was mixed with soil, sorption increased for ^sup 3^H-estradiol but decreased for ^sup 14^C-testosterone. This may have been because poultry litter slowed the transformation of parent hormones. Our results show that poultry litter could have important effects on the mobility of estradiol and testosterone.
Abbreviations: CEC, cation exchange capacity; DOM, dissolved organic matter; HPLC, high-pressure liquid chromatography.
(ProQuest: ... denotes formulae omitted.)
The presence of estrogens (estradiol, estrone, and estriol) and androgens (testosterone) in land-applied manures and domestic and industrial waste, even in very low concentrations, has become a growing concern due to their adverse effect on endocrine systems of humans and wildlife (Ying et al., 2002). Although estradiol and testosterone help to regulate secondary sex characteristics under normal conditions, chronic exposure to these steroids has been associated with abnormal physiological processes and reproductive abnormalities in birds (Moccia et al., 1986), turtles (Bishop et al., 1991), and mammals (Martineau et al., 1988). Land-applied manures and...