17β-Estradiol and Testosterone Sorption in Soil with and without Poultry Litter
- M. Beraa,
- D. E. Radcliffe *b,
- M. L. Cabrerab,
- W. K. Vencillb,
- A. Thompsonb and
- S. Hassanb
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 14C-labeled testosterone and 3H-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. 14C-testosterone sorption in soil increased from 2 to 48 h and remained relatively constant thereafter. 3H-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 (Kd) in soil for 14C-testosterone (20.2 mL g−1) was similar to that for 3H-estradiol (19.6 mL g−1) in single-sorbate experiments. When hormones were applied together, sorption of both hormones in soil decreased, but the 14C-testosterone Kd (12.5 mL g−1) was nearly twice as large as the 3H-estradiol Kd (7.4 mL g−1). We propose this resulted from competition between the hormones and their transformation products for sorption sites, with 14C-testosterone and its expected transformation product (androstenedione) being better competitors than 3H-estradiol and its expected transformation product (estrone). When poultry litter was mixed with soil, sorption increased for 3H-estradiol but decreased for 14C-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.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2011. . Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.