Abstract:
Fluoroquinolone antibiotics have been extensively used in clinical treatments for human and animal diseases. However, their long-term presence in the environment increases the risk of producing resistance genes and creates a potential threat to ecosystems and the health of humans and animals. Batch equilibrium experiments were utilized to investigate the adsorption and retention behavior and mechanism of the quinolone antibiotic enrofloxacin (ENR) in farmland soil in North China. The adsorption and desorption kinetics of ENR in soil were best fitted by pseudo-second-order model (R2 > 0.999). Both the adsorption and desorption processes of ENR in soil reached equilibrium in 1 h. The desorption amounts of ENR were significantly lower than the adsorption amounts, with the hysteresis coefficient (HI) being less than 0.7. The adsorption thermodynamic process of ENR followed the Linear and Freundlich models (0.965 < R2 < 0.985). Hydrophobic distribution and heterogeneous multimolecular layer adsorption were identified as critical factors in the adsorption process. The adsorption amount of ENR gradually decreased with increasing temperature and the initial concentration of ENR. The adsorption rate of ENR was above 80%, while the desorption rate remained below 15%, indicating strong retention ability. The adsorption rate of ENR in soil decreased with increasing pH, the adsorption rate reached 98.3% at pH 3.0 but only 31.5% at pH 11. The influence of coexisting ions on adsorption primarily depended on their properties, such as ion radius, ionic strength, and hydrolysis properties, and the inhibition of adsorption increased with increasing ionic strength. These findings contribute to understanding the fate and risk of veterinary antibiotics in loess soil in North China.
摘要:
氟喹诺酮类抗生素已广泛用于人类和动物疾病的临床治疗。然而,它们在环境中的长期存在增加了产生抗性基因的风险,并对生态系统以及人类和动物的健康造成潜在威胁。采用批量平衡实验研究了喹诺酮类抗生素恩诺沙星(ENR)在华北农田土壤中的吸附和保留行为及其机理。用拟二阶模型(R2>0.999)拟合了ENR在土壤中的吸附和解吸动力学。ENR在土壤中的吸附和解吸过程均在1h内达到平衡。ENR的解吸量明显低于吸附量。滞后系数(HI)小于0.7。ENR的吸附热力学过程遵循线性和Freundlich模型(0.965