|Wang, Qiquan - UNIVERSITY OF CALIFORNIA|
Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: December 15, 2005
Publication Date: March 26, 2006
Citation: Wang, Q., Yates, S.R. 2006. Sulfadimethoxine degradation in manure as affected by initial concentration, moisture, and temperature. American Chemical Society National Meeting. Paper No: AGRO 38/C104, General Oral Presentations. Atlanta, GA, March 26-30, 2006. Technical Abstract: The degradation kinetics of sulfadimethoxine, a widely used sulfonamide antibiotic, in manure under aerobic condition was investigated. Based on the first-order kinetics and the assumption of the availability of sulfadimethoxine in manure for the degradation process, a new kinetic model was developed and was found to fit the degradation kinetics well. The degradation rate in sterilized manure was found to be much lower than in non-sterilized manure, indicating that microorganisms are responsible for a significant portion of degradation of this antibiotic in manure. In non-sterilized manure, the degradation rate constant decreased with increasing initial concentration of sulfadimethoxine, implying that the bioactivity of degrading microorganisms was gradually inhabited. Increasing moisture and temperature greatly enhanced the degradation of sulfadimethoxine. Model calculation results showed that both the degradation rate and the desorption rate of sulfadimethoxine from manure particles increased along with increasing moisture and temperature. Mixing highly contaminated manure with less contaminated, while keeping manure at a high moisture and storing the manure in a moderately warm place under aerobic conditions, can greatly enhance the degradation of sulfadimethoxine in manure. This approach will effectively eliminate this contaminant from the environment.