| Butylene fipronil, a kind of N-substituted phenyl pyrazole compound, was designed and synthesized by Dalian Regar pesticides limited company based on fipronil molecular structure. In order to evaluate environment action of butylene fipronil in water, soils and spinach and the degradation dynamic, degradation mechanism and influence factor, the research studys systemly on detection methods, degradation in water and influence factor, absorption in soils and influence factor, degradation dynamic in spinach and the effect on physiology and biochemistry of spinach. The result of research as follows.1. A method was developed for determination of butylene fipronil residue in spinach, water and soil by solid phase extraction-gas chromatography/mass spectrometry (SPE-GC/MS). The residual of Butylene fipronil were extracted with acetonitrile in spinach and extacted three times with ethyl acetate in water and soils.The extracted solution mixed with NaSO4, NaCl in sequence and then purified by PSA solid phase extraction (SPE).The method was convenient, rapid and showed a good reproducibility. The relative standard deviation of this method was lower than10% (n=6), and the detection limits of butylene fipronil was 0.01mg/L, the quantity detection limits was 0.05mg/kg and good linearity in the range of 0.05mg/L-50mg/L was obtained. The paper studied the fragmentation mechanism of butylene fipronil preliminarily according to its mass spectrometry.2. Photo-degradation of butylene fipronil in aqueous solution was studied considered light source, condense of butylene fipronil in aqueous solution, tempareture, pH value and chemical matters and so on. The result of study showed that the photo-degradation of butylene fipronil could be described by first-order kinetics in water, 0.01mol/L CaCl2 solution, methanol, ethyl acetate and hexane under UV light, the half life was 2.69,2.67,6.30,5.63 and 1.52 hours with temperature at 27℃, but hardly degraded in acetone. Photo-degradation of butylene fipronil conformed to first-order kinetics in water, 0.01mol/L CaCl2 solution and ethyl acetate under sun light, the half life was 2.78, 2.85 and 5.74 hours, but no reaction in hexane, acetone and methanol abviosly. The experiment also studied the effect of light sources, concentration, temperatures and pH value on degradtion rate in order to provide science theory to support application of butylene fipronil. Photo-degradation rate was faster under UV with temperatures increased, when temperature at 7℃, 15℃and 27℃, half time was 7.26h, 3.04h and 1.99h respectively. Photo-degradation rate was different under UV with different pH value, when pH7.0, half time was 2.16h, but with pH value increased or decreased, photo-degration rate became slow, 2.56h when pH4 and 2.41h when pH10. Some chemical compounds were added into aqueous solution of butylene fipronil such as hydrogen peroxide, TiO2, acetone, humic acid, FeSO4, FeSO4+H2O2 (1:1), sodium dodecylbenzenesulfonate, carbamide and tween 80, all these chemical compounds were excited-state quenchers and delayed photo-degradation rate of butylene fipronil in aqueous solution. The chemical structure of photolysis products were studied by gas chromatography mass spectrometry, the results show that photolysis products mainly were fipronil, 3-cyanogen group-5- methallyl amido-1-(2,6-dichlone-4-benzotrifluoride) pyrazole and 3-cyanogen-4-trifluoride-group-5- methallyl amido-1-(2,6-dichlone-4-benzotrifluoride) pyrazole according molecular structure of butylene fipronil and photolysis products'mass spectrometry.3. Adsorption-desorption and eluviation of butylene fipronil in different style soils were investigated and IR of butylene fipronil, and IR of butylene fipronil's reciprocity with humic acid and kaolin clay were studied. There two obvious processes during adsorption course in soils: rapid linearily distribution and low adsorption. Adsorption could be finished whitin 24 hours and the quantity of adsorption by soils had positive correlation with content of organic matter, cation exchange capacity and cosmid in soils. Adsorption-desorption isoterms of butylene fipronil in 5 kind soils were non-linear, and Freundlich equation could describe this course appropriately, coefficient of correlation were greater than 0.97. The results of desorption indicated that the hysteresis phenomena appeared during the desorption prosess, and the hysisters coefficient of butylene fipronil in the 5 soils studied varied from 0.89 to 0.98, which show that there were irreversible chemical adsorption besides physical adsorption. IR of butylene fipronil, humic acid and kaolin clay were studied with infrared analysis technology, and compare them with IR of butylene fipronil-humic acid and butylene fipronil- kaolin clay, elaborated the adsorption mechanism of butylene fipronil in soils. Experiment studied the leaching character of butylene fipronil in 5 kind soils and its influence factors such as organic maters, soil clay and cation exchange capacity. With these ingredients increased, soils could adsorb more butylene fipronil, which was not easy to be leached into lower surface soil, mainly stayed in upper layer 0cm to 5cm of 1#, 3# and 5# soils. Because lower content of organic maters, soil clay and cation exchange capacity in 2# and 4# soil, butylene fipronil was easy to be leached into lower and leaching ability got strong relatively, range enlarge from 0 cm to 15 cm of butylene fipronil in 2# and 4# soils.4. The degradation residual dynamics in spinach and soils were studied after butylene fipronil emulsifiable concentrate 5% application in farm, meanwhile, enzyme activity of peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) and quantity of malondialdehyde (MDA) were determined in order to study the effects of butylene fipronil on physic-cology and biochemistry of spinach. The results show that degradation residual dynamics of butylene fipronil emulsifiable concentrate 5% in spinach and soils could be described by the first order kinetic equiation, and the half time was 1 day in spinach and about 2 days in soils, butylene fipronil belongs to easily degradable pesticides. The degradation residual dynamics in different depth soils were studied after doubled recommended dosage were insufflated. The result show thatwith time go on, butylene fipronil could be absorbed by soils and infiltrated depth was 40 cm after 50 days later. Experiments also studied the influence of different concentration butylene fipronil on enzyme activity and MDA quantity in spinach leaves. The results were observed that there were none enzyme activity influenced except for POD, and the quantity of MDA without change obviously, after 7 days later, the activity of POD returned to normal level which indicated that the spinach was safety after applicated butylene fipronil 7 days according recommended dosage.
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