Yang Ji-Feng, Ying Guang-Guo, Yang Li-Hua, Zhao Jian-Liang, Liu Feng, Tao Ran, Yu Zhi-Qiang, Peng Ping'an
State Key Laboratory of Organic Geochemistry, Chinese Academy of Sciences, Guangzhou Institute of Geochemistry, Guangzhou, China.
J Environ Sci Health B. 2009 Mar;44(3):241-8. doi: 10.1080/03601230902728245.
This study investigated the degradation of sulfadiazine in three soils and also determined its sorption and hydrolysis behaviors as well. At the spike concentration of 10 mg/kg, the half-lives for sulfadiazine in the aerobic nonsterile soils ranged from 12 days to 18 days. Sulfadiazine was more persistent in the anoxic soils with the half-lives ranging between 57 days and 237 days and soil microorganisms played little role in the dissipation process under anoxic conditions. The decline in sulfadiazine concentrations was also observed in the sterile soils under aerobic conditions. Hydrolysis could not explain this phenomena as hydrolysis of sulfadiazine was pH dependent. Sulfadiazine only hydrolyzed to a very limited degree at acidic pH. Increased sorption was observed for sulfadiazine in soil 1 (pH 4.3) when the contact time increased to 14 days, but no significant increase in sorption was found for soil 2 (pH 7.2) and soil 3 (pH 8.5).