为了研究抗生素在华南地区农业环境中的行为特征,采用批平衡试验研究了泰乐菌素在华南地区典型农业土壤上的吸附动力学和热力学特性.结果表明:泰乐菌素的吸附与土壤的pH呈负相关,与w(OC)没有明显的相关性;泰乐菌素的吸附动力学符合二级动力学模型,吸附速率可能主要由颗粒间扩散过程控制;吸附是自发进行的吸热过程.研究显示,泰乐菌素易在南亚热带农业土壤中残留,应当重视其潜在的环境风险.
In order to understand the environmental behavior of antibiotics on agriculture soil in South China,a typical veterinary drug, tylosin,was investigated using batch experiments to determine its sorption kinetic and thermodynamic properties on the four typical agricultural soils in South China. The results showed that the sorption of tylosin was negatively correlated with the pH of the soil,with no significant correlation with organic matter content. A pseudo second-order rate equation could fit the sorption data well,indicating that the sorption rate might be controlled by intra-particle diffusion process. Sorption was a spontaneous and endothermic process. This study suggests that tylosin tends to remain in the agriculture soil of south subtropical regions,and its potential environmental risk should be considered.