Sukul Premasis, Lamshöft Marc, Zühlke Sebastian, Spiteller Michael
Institute of Environmental Research (INFU), University of Dortmund, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany.
Chemosphere. 2008 Mar;71(4):717-25. doi: 10.1016/j.chemosphere.2007.10.045. Epub 2008 Feb 20.
Photolysis of 14C-sulfadiazine in aqueous solution under simulated sunlight followed first-order kinetics. The impact of H2O2, humic acid, fulvic acid and acetone to enhance the photodegradation of sulfadiazine (SDZ) was studied. Six photoproducts, 4-OH-SDZ, 5-OH-SDZ, N-formyl-SDZ, 4-[2-iminopyrimidine-1(2H)-yl] aniline, 2-aminopyrimidine, and aniline were identified. Extrusion of SO2 was found to be the main degradation process during irradiation. These photoproducts can occur in water and soil upon sunlight exposure, when soil is treated with SDZ contained in manure. Due to photodegradation the experimental half-life of the SDZ in water was 32h and in the presence of photosensitizers the half-life values were 19.3-31.4h, 17.2-31.4h, 12.6-29.8h, and 3.8-30.7h for H2O2, humic acid, fulvic acid, and acetone, respectively depending on the concentration of the photosensitizers. The presence of photosensitizers markedly reduced SDZ persistence, indicating that indirect photolytic processes are important factors governing the photodegradation of SDZ in aqueous environments. Investigation revealed further persistence behavior of SDZ in manure. The half-life value of SDZ in manure was 158h.
在模拟阳光下，水溶液中14C-磺胺嘧啶的光解遵循一级动力学。研究了过氧化氢、腐殖酸、富里酸和丙酮对增强磺胺嘧啶（SDZ）光降解的影响。鉴定出六种光产物，即4-羟基-SDZ、5-羟基-SDZ、N-甲酰基-SDZ、4-[2-亚氨基嘧啶-1(2H)-基]苯胺、2-氨基嘧啶和苯胺。发现辐照过程中SO2的逸出是主要降解过程。当用粪便中含有的SDZ处理土壤时，这些光产物在阳光照射下会出现在水和土壤中。由于光降解，SDZ在水中的实验半衰期为32小时，在存在光敏剂的情况下，根据光敏剂的浓度，过氧化氢、腐殖酸、富里酸和丙酮的半衰期值分别为19.3 - 31.4小时、17.2 - 31.4小时、12.6 - 29.8小时和3.8 - 30.7小时。光敏剂的存在显著降低了SDZ的持久性，表明间接光解过程是控制水环境中SDZ光降解的重要因素。研究还揭示了SDZ在粪便中的进一步持久性行为。SDZ在粪便中的半衰期值为158小时。
