2006 Annual Report 4d.Progress report. This report serves to document research conducted under a specific cooperative research agreement between the USDA and the University of California, Riverside. Additional details of research can be found in the report for the parent project 5310-12130-007-00-D. Methods Were Developed to Reduce Pharmaceutical Pollution. Sulfadimethoxine is a widely used sulfonamide veterinary antibiotic and a source of agricultural contamination; therefore, information is needed about its degradation kinetics in manure under aerobic conditions. Based on an analysis of first-order kinetics and the assumption that sulfadimethoxine availability for degradation in manure could be limiting, a new kinetic model was developed and was found to fit the degradation kinetics well. The degradation rate in sterile manure was found to be much lower than in non-sterile manure, indicating that biodegradation is important in degrading this compound. Increasing moisture, temperature, and mixing fresh manure with contaminated manure was found to increase sulfadimethoxine degradation. This research provides information that can be used to greatly diminishing sulfadimethoxine contamination and significantly reducing sulfadimethoxine inputs into the environment.