Research On Environmental Behaviors And Pollution Control Technology Of Florfenicol And Olaquindox

With the development of animal husbandry, veterinary drugs are widely used to treat diseases, infeetion every year and exereted into the environment more and more; Veterinary drugs pollution on ecological environment is becoming heavier. Thus, research objectives should be focused on not only the veterinary drugs pharmacology and toxicology, but also the environmental behaviors and pollution control technology.Widely-used as veterinary medicine in the animal and poultry production, the metabolites of florfenicol and olaquindox are complex and various in animal, and approximately 25%～75% dugs and its metabolites can enter the environment with stable manure, impacting on the eco-environment and human health. Now, there was little research about environmental behaviors and pollution control technology of florfenicol and olaquindox. In order to provided basic data for environmental risk assessmen and pollution control, the transport and degradation of florfenicol and olaquindox in environmental and influeneing factors, the pollution control technology of olaquindox and its metabolites(MQCA) of simulated biological reactor in pig manure were studied. The results are briefly summarized as below:Firstly, methods for detecting the residue of florfenicol and olaquindox in soils and water was established. The result showed:useing Supersonic Method, the sample was extracted with methanol,60℃ultrapure water and cleansed with LC-C18, HLB solid phase extraction cartridge for florfenicol and olaquindox respectively. The method has good linear, low detection limit, high recovery in soils, good reproducibility and is suitable to detect florfenicol and olaquindox in acidic, basic and neutral soils; A methods for detecting the residue of olaquindox and its metabolite 3-methylquinoxaline-2-carboxylic acid(MQCA) in pig manure was established. Useing Supersonic Method at room temperature, the sample was extracted with 5%methanol, cleansed with HLB solid phase extraction cartridge and tested with LC-MS. The method has low detection limit, high recovery in the manure and is suitable to detect the olaquindox and MQCA in the pig manure. Secondly, degradation behaviors of florfenicol and olaquindox were investigated under the condition of soil and water. Degradation and its influencing factors of florfenicol and olaquindox in soils was mainly studyied in five kind of soils. The results indicated that florfenicol degraded relatively fast in northeast black soil, Shanxi fluvo-aquic soil, Fujian paday soil and slowly In Jiangxi red soil and Changshu paday soil, the degradation half life were 15.1d,2.5d,10.6d,68.0d and 77.Od respectively; Olaquindox degraded relatively fast in five tested soil and the degradation half life under 22.Od. The degradation of olaquindox is easier in alkaline soil. Microorganisms play a significant role for the degradation of florfenicol and olaquindox. High-temperature is beneficial to the degradation of florfenicol and olaquindox in soils.Hydrolysis of florfenicol and olaquindox was studied under the condition of different pH value and temperature. The result showed:at temperature of 25℃, hydrolysis of florfenicol was slow in pH 4 and fast in pH 4,9, and the half life was 533.2d,105.0d and 231.0d respectively; At temperature of 25℃, olaquindox was very stable in pH 4,7,9. The hydrolysis rate of florfenicol increased at higher temperatures; At temperature of 50℃, the hydrolysis half-time of florfenicol were 77.0d,73.0d and 4.1d, well below its at 25℃. Temperature had no effect on the hydrolysis of olaquindox in pH 4,7; However, high temperature was beneficial to the hydrolysis of olaquindox and the hydrolysis half-time of it were 3465d and 247d at temperature of 25 and 50℃. Temperature could affect the hydrolysis rate of olaquindox under the alkaline condition.Thirdly, the adsorption and leaching behavior and its affecting factors of florfenicol and olaquindox in different soils in the laboratory were investigated using batch equilibration technique. The sorption behavior of florfenicol and olaquindox in five soils could be well fitted by both the Langmuir and Freundlich model. Sorption distribution coefficients KF for five tested soils were very small, suggesting that florfenicol and olaquindox could not be easely adsorbed on soils; There were good correlations between KF of florfenicol and olaquindox on the five different kinds of soils and the soil properties, such as organic matter and cation exchange capacity. Temperature could affect the sorption of florfenicol and olaquindox on soil and the lower temperature was favorable to the sorption of olaquindox on soil; Lower ionic strength were favorable to the sorption of olaquindox on soil. florfenicol is easier to move in the five tested soils; Olaquindox is difficult totransfer in northeast black soil, and easer in Jiangxi red soil, Changshu paday soil, Shanxi fluvo-aquic soil and Nanjing yellow brown soil; The contentof organic materials and CEC has obvious influence on its mobility.Fourthly, In use of simulated biological reactor technology, the pollution control of olaquindox and its metabolites(MQCA) were explored and researched. The result showed:olaquindox in pig manure rapidly degraded into MQCA, and MQCA also degraded fastly in simulated biological reactor. Biological reactor technology is an effective measure to control the pollution of olaquindox and its metabolites(MQCA).