|Sikora, Lawrence -|
Submitted to: Journal of Environmental Quality
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 2, 2011
Publication Date: July 8, 2011
Citation: Hakk, H., Sikora, L. 2011. Dissipation of 17B-estradiol in composted poultry litter. Journal of Environmental Quality. 40:1560-1566. Interpretive Summary: 17ß-estradiol and testosterone are potent endocrine disrupting compounds that can enter the environment from stored animal waste or waste used to fertilize fields. A mixture of poultry litter, wood chips and straw was amended with radiolabeled 17ß-estradiol or testosterone and allowed to undergo laboratory scale heated (HC) and room temperature (RTI) decomposition. Radiolabel in the finished products was separated into water-extractable, acetone-extractable, non-extractable and mineralized fractions. Levels of 17ß-estradiol-derived residues in these fractions were not different between the treatments, but less of the dose was metabolized to CO2 during heated composting than during room temperature incubation. Estrone was the major degradation product present in extracts of both treatments, a metabolite with less biological activity than the parent. 17ß-estradiol was still present as a minor constituent, but its concentration was substantially reduced in both litter treatment methods. Heated composting or room temperature incubation did not affect the concentration of testosterone-derived radioactivity into the solvent-extracted fractions; nor did either degradation method affect the level of testosterone metabolized into CO2. Multiple metabolites of testosterone were identified; none with known biological activity, and a significantly reduced level of parent compound was also measured. The data suggested that unmanaged, static manure piles may produce similar results to aerobic, heated composting with regard to degradation and immobilization of steroid hormones in animal waste, but may be a less costly and time-consuming management method for the food animal producer.
Technical Abstract: The effects of heated composting and ambient temperature poultry waste decomposition on the fate of 17ß-estradiol and testosterone were determined in separate experiments. A mixture of poultry litter, wood chips and straw was amended with [14C]17ß-estradiol or [14C]testosterone and allowed to undergo laboratory scale heated (HC) and room temperature (RTI) decomposition for 24 and 23d, respectively. Radiolabel in the finished products was fractionated into water-extractable, acetone-extractable, non-extractable and mineralized fractions. Total radioactive residues (TRR) after 17ß-estradiol administration to HC and RTI (n=2) treatments were not different (P > 0.05) in any compartment except that statistically less was mineralized to 14CO2 during HC than RTI (1.1% versus 10.0% for HC and RTI, respectively). Estrone was the major degradation product present in acetone extracts of HC and RTI treatments, with 17ß-estradiol present as a minor constituent. Non-extractable fractions were partitioned, and the major portion of radiolabel in HC was associated with fulvic acid; in RTI humin fractions contained nearly equal radiolabel percentages. Treatment did not quantitatively affect (P < 0.05) partitioning of radioactivity from [14C]testosterone administration. Multiple metabolites of testosterone were characterized in the acetone extracts by (+)LC/MS, representing either oxidized or isomerized by-products of the parent testosterone. Unmanaged, static manure piles may produce similar results with regard to degradation and immobilization of steroid hormones in animal waste to heated composting, but may be a less costly and time-consuming management method for the food animal producer.