【作者】 曹维强；

【导师】 王静；

【作者基本信息】 中国农业科学院 ， 农产品质量与食物安全， 2010， 博士

【摘要】 丁烯氟虫腈是我国自主设计并合成的一种N-取代苯基吡唑类新型农药,为了正确评价丁烯氟虫腈环境行为,探明其在水中、土壤中以及菠菜中的降解动态及降解机理和影响因素,本课题对丁烯氟虫腈的检测方法、在水中的降解及影响因素、在土壤中的吸附及影响因素以及在菠菜中降解动态及对菠菜生理生化的影响等方面进行了系统的研究,研究内容及结果如下:1.丁烯氟虫腈在菠菜、水和土壤中的气相色谱-质谱联用检测方法的建立。研究建立了固相萃取(SPE)气相色谱-质谱(GC-MS)测定丁烯氟虫腈残留量的分析方法。研究结果表明菠菜用乙腈提取,水和土壤用乙酸乙酯提取,提取液加无水硫酸钠、氯化钠,过PSA固相萃取柱,采用GC-MS进行检测,方法简单、快速、重现性良好,相对标准偏差小于10%;检测限(S/N=3)为0.01mg/L,定量限为0.05mg/kg,在0.05mg/L -50mg/L范围内具有良好的线性关系,并对质谱图中丁烯氟虫腈的裂解进行了初步解析。2.研究了光源种类、丁烯氟虫腈的浓度、光降解温度、水溶液pH值以及溶液中添加不同化学物质对丁烯氟虫腈光降解动态的影响。研究表明:紫外光和自然光对丁烯氟虫腈的降解影响最大,27℃下,30W紫外灯40cm紫外光照射,丁烯氟虫腈在水中、0.01mol/L氯化钙溶液、甲醇、乙酸乙酯和正己烷中的降解符合一级反应动力学,降解半衰期分别为2.69h、2.67h、6.30h、5.63h和1.52 h,,而在丙酮中不降解;而在日光照射下,丁烯氟虫腈在水中、0.01mol/L氯化钙溶液、乙酸乙酯中的降解反应符合一级反应动力学,降解半衰期分别为2.78h、2.85h和5.74h,而在甲醇、正己烷和丙酮中没有发生明显的降解反应;丁烯氟虫腈水溶液在7℃、15℃和27℃条件下,分别用相同的紫外灯照射,其光降解半衰期t1/2分别为7.26h、3.04h和1.99h,表明随着温度的升高,丁烯氟虫腈在水溶液中的光降解速度加快;在相同的温度和紫外光的照射下,不同的pH值溶液中丁烯氟虫腈所表现出的降解动态有所不同,在中性水中降解半衰期最短,降解速度最快,光降解半衰期t1/2=2.16h,而在pH4和pH10溶液中半衰期变长,降解速度放慢,光降解半衰期分别为2.56h和2.41h;在丁烯氟虫腈水溶液中添加了过氧化氢、二氧化钛、丙酮、腐殖酸、硫酸亚铁、硫酸亚铁+过氧化氢、十二烷基苯磺酸钠、尿素以及土温80等化合物,结果表明以上化合物不同程度的减缓了丁烯氟虫腈的光降解速度,表现出一定的光淬灭性;水溶液中的丁烯氟虫腈,其水解速率随着温度的升高和pH值的降低而加快,水解反应符合一级反应动力学方程;对丁烯氟虫腈紫外光照射后产生的新物质利用气相色谱-质谱仪进行分析,结合丁烯氟虫腈的化学结构和光降解物的质谱图,结合质谱解析技术推断出可能的降解产物为:3-氰基-5-甲代烯丙基氨基-1-(2,6-二氯-4-三氟甲基苯基)吡唑(a)、氟虫腈(b)和3-氰基-4-三氟甲基-5-甲代烯丙基氨基-1-(2,6-二氯-4-三氟甲基苯基)吡唑(c)。3.试验研究了丁烯氟虫腈在不同土壤中的吸附-解吸作用、淋溶作用以及利用红外光谱技术研究了丁烯氟虫腈与土壤中重要的成份腐植酸和高岭土的相互作用机理。研究结果表明:丁烯氟虫腈在土壤中的水解速率符合一级反应动力学方程,且随着温度的升高而加快;丁烯氟虫腈在土壤中的吸附过程分为2个较为明显的阶段:快速的线性分配阶段和慢速的吸附阶段,并且在24h内能够达到吸附平衡,确定丁烯氟虫腈的吸附平衡时间为24h,吸附量与土壤中有机质成份、阳离子交换量和粘粒含量成正相关;丁烯氟虫腈的吸附-解吸过程表现为非线性, Freundlich方程很好地拟合了丁烯氟虫腈的吸附和解吸等温线,拟合度均大于0.97,丁烯氟虫腈在土壤中的吸附-解吸过程存在一定的滞后现象,滞后系数从0.89-0.98,说明丁烯氟虫腈的吸附除物理作用外,还存在不可逆的化学吸附,导致解吸滞后现象的出现;利用红外光谱技术研究了丁烯氟虫腈、腐植酸以及高岭土的红外光谱图,并与丁烯氟虫腈与腐植酸和高岭土相互作用后的红外光谱图进行了比较,解析了相互作用的机理;研究了丁烯氟虫腈在不同土壤中的淋溶特性,对于有机质、粘粒含量和阳离子交换量较高的1#、3#和5#土壤来说,丁烯氟虫腈的淋溶作用较弱,主要存在于土壤0cm-5cm的表层,而对于有机质、粘粒含量和阳离子交换量较低的2#和4#土壤来说,淋溶作用相对较强,丁烯氟虫腈主要存在于0cm-15cm深度土壤中。4.研究了不同浓度的5%丁烯氟虫腈乳油在以菠菜为试验作物进行喷施后,在菠菜和土壤中的降解残留动态,以及喷施农药后通过测定菠菜叶片中POD、SOD、CAT等酶的活性以及MDA的含量研究丁烯氟虫腈对菠菜生理生化活动的影响。研究结果表明:不同剂量的5%丁烯氟虫腈乳油喷施在菠菜叶面上和土壤中以后其降解动态符合一级反应降解动力学方程,菠菜中降解半衰期均在1d左右,推荐剂量土壤中的降解半衰期为2.16d,属于易降解农药;以2倍推荐剂量研究不同深度土壤中丁烯氟虫腈的残留动态,表明随着时间的推移,丁烯氟虫腈能够驻留在土壤中,并有一定的迁移性,经过50d,其迁移深度达到40cm,但浓度已经低于检测定量限;研究了不同剂量的5%丁烯氟虫腈乳油喷施在菠菜叶面上以后对菠菜生理生化反应的影响,结果显示除POD酶活性增加外,其他酶的活性和丙二醛的含量同对照相比,没有发生明显的变化,推荐剂量和2倍推荐剂量与空白相比对POD酶活性的影响在第7d时,已经没有明显差别,甚至略低于空白对照的过氧化物酶活性,表明丁烯氟虫腈对菠菜生理活性的影响不大,按照规定剂量喷施丁烯氟虫腈,7d后食用菠菜是安全的。更多还原

【Abstract】 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.更多还原