ARS | Publication request: 17B-estradiol in runoff as affected by various poultry litter application strategies

Submitted to: Science of the Total Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 16, 2012
Publication Date: N/A

Interpretive Summary: Estrogen runoff from manure applications may have negative environmental consequences. The objective of this study was to determine what factors affect 17B-estradiol runoff when poultry litter is applied to pastures. Rainfall simulations were conducted on plots fertilized with litter and the effects of the following treatments on estrogen runoff were evaluated; 1) aluminum sulfate (alum) additions to poultry litter; 2) litter from birds fed diets made with phytase or high available phosphorus (HAP) corn; 3) fertilizer type; 4) poultry litter application rate; and 5) time until the first runoff event occurs after poultry litter application. Results showed that increasing alum additions to poultry litter decreased estrogen concentrations in runoff water. Estrogen concentrations in runoff water were highest from poultry litter from birds fed phytase diets compared to other diets. Triple superphosphate applications resulted in the lowest 17B-estradiol concentrations in runoff water among all fertilizer treatments. Estradiol concentrations in runoff water were also shown to increase with increasing poultry litter application rates and decreased with time until the first runoff event. This research indicated that litter rate, timing and treatment with alum all reduce estrogen runoff from pastures fertilized with poultry litter.

Technical Abstract: Runoff of estrogen from land fertilized with poultry litter has recently received increased attention. The objective of this study was to determine the effects of various poultry litter application strategies on 17B-estradiol concentrations in runoff water. Treatments included the effects of 1) alum application rates to poultry litter; 2) litter from birds fed modified diets; 3) fertilizer type; 4) poultry litter application rate; and 5) time until the first runoff event occurs after poultry litter application. Rainfall simulators were used to cause continuous runoff from fertilized plots. Runoff samples were collected and analyzed for 17B-estradiol concentrations. Results showed that increasing alum additions to poultry litter decreased estrogen concentrations in runoff water. Estrogen concentrations in runoff water were highest from poultry litter from birds fed phytase diets. Triple superphosphate applications resulted in the lowest 17B-estradiol concentrations in runoff water among all fertilizer treatments. Estradiol concentrations in runoff water were also shown to increase with increasing poultry litter application rates and decreased with time until the first runoff event. This research indicated that litter rate, timing and treatment with alum all reduce estrogen runoff from pastures fertilized with poultry litter.