【作者】 刘永涛；

【导师】 贠克明；

【作者基本信息】 山西医科大学 ， 法医学， 2011， 硕士

【摘要】 目的1.建立拟除虫菊酯类农药在保存检材和埋葬犬尸体中的分解动力学模型;2.改进生物检材中拟除虫菊酯类农药的气相色谱法检测方法,建立GC-ECD、GC/MS检测方法;3.研究拟除虫菊酯类农药在保存检材中的分解动力学、埋葬犬尸体内的分解动力学。方法1.保存检材中分解动力学1.1分组和染毒甲氰菊酯、氯氰菊酯和氰戊菊酯实验组,每实验组犬6只,染毒剂量分别为8LD₅₀、10LD₅₀和10LD₅₀农药原液（按大鼠与犬体型系数推算）,每只犬在2min内经口灌胃染毒。1.2分解动力学研究犬死亡后,立即取血和肝脏。每只犬的血分四等份,分别置于-20℃、4℃、20℃、20℃（1%NaF）环境中保存;每只犬的肝分四等份,分别置于-20℃、4℃、20℃、20℃（4%甲醛）保存,于死后不同时间点二氯甲烷提取,气/质联用法、气相色谱法定性定量检测保存检材中甲氰菊酯、氯氰菊酯和氰戊菊酯的含量,WinNonlin软件拟合分解动力学方程,计算甲氰菊酯、氯氰菊酯和氰戊菊酯在不同条件保存样品中的分解半衰期。2.埋葬犬尸体中分解动力学2.1时间对埋葬尸体中分解动力学的影响2.1.1分组和染毒甲氰菊酯、氯氰菊酯和氰戊菊酯实验组,每实验组犬33只,染毒剂量分别为8LD₅₀、10LD₅₀和10LD₅₀农药原液（按大鼠与犬体型系数推算）,每只犬在2 min内经口灌胃染毒。2.1.2埋葬分解动力学研究犬死亡后,0d的立即解剖取材,将检材放置-20℃冰箱待检,其余装入双层塑料袋中,封口机封一半袋口,埋藏于100 cm 100 cm 150cm的坑内。甲氰菊酯组于埋藏后35d,65d,95d,125d,200d,383d,503d挖掘;氯氰菊酯组于埋葬后30d、60d、90d、210d、360d和480d挖掘;氰戊菊酯组于埋葬后30d、52d、82d、200d、350d和470d挖掘,每次各解剖3只,取材,二氯甲烷提取,GC/MS法、GC-ECD法定性、定量检测其中甲氰菊酯、氯氰菊酯和氰戊菊酯含量。2.2染毒剂量对埋葬尸体中分解动力学的影响2.2.1分组和染毒:甲氰菊酯、氯氰菊酯和氰戊菊酯实验组,每实验组犬6只,每个实验组再随机分两组染不同剂量农药,甲氰菊酯分4LD₅₀和8LD₅₀两个剂量组、氯氰菊酯分2LD₅₀和10LD₅₀两个剂量组、氰戊菊酯分2LD₅₀和10LD₅₀两个剂量组,每只犬在2 min内经口匀速灌胃染毒。2.2.2埋葬分解动力学研究犬死亡后,装入双层塑料中,封口机封一半袋口;埋藏于100 cm 100 cm 150cm的坑内。于埋藏60d后挖掘解剖取检材,二氯甲烷提取,GC/MS法、GC-ECD法定性、定量检测其中甲氰菊酯、氯氰菊酯和氰戊菊酯含量。2.3不同埋葬方式对埋葬犬尸体中分解动力学的影响2.3.1分组和染毒甲氰菊酯、氯氰菊酯和氰戊菊酯实验组,每实验组犬9只,染毒剂量分别为8LD₅₀、10LD₅₀和10LD₅₀农药原液（按大鼠与犬体型系数推算）,每只犬在2 min内经口灌胃染毒。2.3.2埋葬分解动力学研究犬死亡后,每个实验组处理均为:3只装入双层塑料中,封口机封一半袋口;3只装入双层编织袋中,扎口;3只装入60 cm 70 cm 60 cm木箱中,钉盖;均埋藏于100 cm 100 cm 150cm的坑内。于埋藏后60d挖掘解剖取检材,二氯甲烷提取,GC/MS法、GC-ECD法定性、定量检测其中甲氰菊酯、氯氰菊酯和氰戊菊酯含量。2.4埋葬季节（温度）对埋葬犬尸体中分解动力学的影响2.4.1分组和染毒甲氰菊酯、氯氰菊酯和氰戊菊酯实验组,每实验组犬6只,每个实验组再随机分成两组,每组3只,不同时间灌胃染毒埋葬,染毒剂量分别为8LD₅₀、10LD₅₀和10LD₅₀农药原液（按大鼠与犬体型系数推算）,每只犬在2 min内经口灌胃染毒。2.4.2埋葬分解动力学研究犬死亡后,装入双层塑料中,封口机封一半袋口;埋藏于100 cm 100 cm 150cm的坑内。甲氰菊酯组其中3只于09/3/21以8LD₅₀剂量灌胃染毒致死后埋葬,于09/6/6（75d后）挖出,另3只同剂量同方式处死,与09/8/24埋葬,于09/11/8（75d后）挖出;氯氰菊酯组和氰戊菊酯组中每组3只于09/4/11以10LD₅₀剂量灌胃染毒致死后埋葬,于09/6/25（75d后）挖出,另3只同剂量同方式处死,与09/8/24埋葬,于09/11/8（75d后）挖出,分别挖掘解剖取材,二氯甲烷提取,GC/MS法、GC-ECD法定性、定量检测其中甲氰菊酯、氯氰菊酯和氰戊菊酯含量。结果1.保存检材中的分解动力学1.1甲氰菊酯不同保存条件下,血和肝中甲氰菊酯均发生分解,其分解符合一级动力学过程,可用公式C_t=A^*e^-αt+B^*e^-βt和C_t=C₀e^-αt表示。-20℃血和肝保存13d时,甲氰菊酯浓度分别下降为初始浓度的82.6 15.2%和98.2±37.6%,-20℃血保存215d时已检测不到甲氰菊酯,-20℃肝保存345d时甲氰菊酯浓度下降为初始浓度的14.7 9.2%,-20℃血和肝分解半衰期分别为:18.07d、40.57d;4℃血和肝保存13d时,甲氰菊酯浓度分别下降为初始浓度的66.3 26.1%和79.1 31.2%,4℃血保存185d时已检测不到甲氰菊酯,4℃肝保存345d时甲氰菊酯浓度下降为初始浓度的0.9 0.9%,4℃血和肝分解半衰期分别为:15.74d、33.90d;20℃血和肝保存13d时,甲氰菊酯浓度分别下降为初始浓度的63.0±28.3%和85.3 32.1%,20℃血和肝分别保存185d和345d时已检测不到甲氰菊酯,其分解半衰期分别为:13.99d、23.68d;20℃（1%NaF）血保存13d时,甲氰菊酯浓度下降为初始浓度的59.8 21.7%,在保存155d时已检测不到甲氰菊酯,其分解半衰期为9.94d;20℃（4%甲醛）肝保存13d和345d时,甲氰菊酯浓度分别下降为初始浓度的94.5 23.9%和35.825.7%,其分解半衰期为51.97d。1.2氯氰菊酯不同保存条件下,血和肝中氯氰菊酯均发生分解,其分解符合一级动力学过程,可用公式C_t=A^*e^-αt+B^*e^-βt和C_t=C₀e^-αt表示。-20℃血和肝保存40d时,氯氰菊酯浓度分别下降为初始浓度的64.4±2.8%和91.1±2.9%,保存290d时氯氰菊酯浓度分别下降为初始浓度的42.0 2.9%和76.4 5.8%,其分解半衰期分别为:182.83d、826.01d;4℃血和肝保存40d时,氯氰菊酯浓度分别下降为初始浓度的54.3±1.4%和79.4±5.8%,保存290d时氯氰菊酯浓度分别下降为初始浓度的26.1 10.9%和50.0 20.5%,其分解半衰期分别为:93.76d、327.18d;20℃血和肝保存40d时,氯氰菊酯浓度分别下降为初始浓度的27.5±3.6%和70.5±2.9%,保存290d时20℃血液中的氯氰菊酯浓度下降为初始浓度的11.5 1.4%,其分解半衰期为:10.54d;20℃（1%NaF）血和20℃（4%甲醛）肝保存40d时,氯氰菊酯浓度分别下降为初始浓度的25.3±0.7%和91.1±2.9%,保存290d时,血液中的氯氰菊酯浓度下降为初始浓度的10.8±0.7%和91.1±2.9%,其分解半衰期分别为5.11d和2288.49d。1.3氰戊菊酯不同保存条件下,血和肝中氰戊菊酯均发生分解,其分解符合一级动力学过程,可用公式C_t=A^*e^-αt+B^*e^-βt和C_t=C₀e^-αt表示。-20℃血和肝保存40d时,氰戊菊酯浓度分别下降为初始浓度的73.6±0.5%和95.6±8.6%,保存290d时氰戊菊酯浓度下降为初始浓度的29.6 4.0%和50.2 4.3%,其分解半衰期分别为:110.08d、347.14d;4℃血和肝保存40d时,氰戊菊酯浓度分别下降为初始浓度的26.4±6.4%和78.3±13.0%,保存290d时氰戊菊酯浓度下降为初始浓度的6.4 0.8%和30.4 4.3%,其分解半衰期分别为:36.84d、226.42d;20℃血和肝保存40d时,氰戊菊酯浓度分别下降为初始浓度的33.7±1.1%和47.8±4.3%,保存228d时,血液中的氰戊菊酯浓度下降为初始浓度的6.5 0.8%,其分解半衰期为:24.00d;20℃（1%NaF）血和20℃（4%甲醛）肝保存40d时,氰戊菊酯浓度分别下降为初始浓度的2.4 1.6%和104.3 4.3%,20℃（1%NaF）血在保存228d时已经检测不到氰戊菊酯,而20℃（4%甲醛）肝在保存290d时氰戊菊酯含量下降到初始浓度的86.94.3%,20℃（1%NaF）血和20℃（4%甲醛）肝中氰戊菊酯半衰期分别为6.18d和763.75d。2甲氰菊酯、氯氰菊酯和氰戊菊酯在埋葬犬体内分解动力学2.1时间对埋葬尸体中分解动力学的影响结果显示:甲氰菊酯组显示:8LD₅₀灌胃致死犬埋葬尸体中各脏器药物含量呈先上升后下降的趋势。埋葬95d后尸体心脏、脾脏、肺脏、肾脏、脑、胸肌、右前肢肌、右后肢肌、心血中甲氰菊酯含量升至最高（1.5³.7倍）,之后至383d下降17.6%⁷1.1%;埋葬383d后胃和肝中甲氰菊酯含量升至最高（37.5⁴8.9倍）;氯氰菊酯组显示:10LD₅₀灌胃致死犬埋葬尸体中各脏器中氯氰菊酯含量呈先上升后下降的趋势。埋葬60d后尸体心脏、脾脏、肺脏、肾脏、脑、胃中氯氰菊酯含量升至最高（1.34⁷.22倍）;而胸肌、右后肢肌至210d后升至最高;右前肢肌至360d升至最高,然后逐渐呈下降趋势;氰戊菊酯组显示:10LD₅₀灌胃致死犬埋葬尸体中各脏器氰戊菊酯含量呈先上升后下降的趋势。埋葬350d后尸体心脏、肝脏、脾脏、肾脏、胸肌中氰戊菊酯含量升至最高（5.2²22.1倍）;胃和脑组织至52d时升至最高,然后逐渐呈下降趋势。2.2染毒剂量对埋葬尸体中分解动力学的影响结果显示:甲氰菊酯、氯氰菊酯和氰戊菊酯实验组均显示:高剂量组埋葬犬尸体中心、肝、肾、脑、胃中农药含量明显高于低剂量组埋葬犬,而肌肉中两剂量组农药含量无明显差异。2.3不同埋葬方式对埋葬尸体中分解动力学的影响结果显示:甲氰菊酯实验组显示:埋葬75d塑料袋包装犬尸体心脏、肺、脑、和胃中甲氰菊酯含量显著高于木箱（棺材）方式埋葬犬,木箱（棺材）方式埋葬犬心脏、肝、脾、脑、胸肌、右前肢肌及右后肢肌中甲氰菊酯含量显著高于编织袋包装犬;氯氰菊酯组显示:埋葬75d塑料袋包装犬尸体心脏、肝、肺、脑和胃中氯氰菊酯含量显著高于木箱（棺材）包装犬,木箱（棺材）包装犬心脏、肝、肺、胃、右前肢肌和右后肢肌中氯氰菊酯含量显著高于编织袋包装犬。氰戊菊酯组显示:埋葬75d塑料袋包装犬尸体心脏、脑、右前肢肌和右后肢肌中氰戊菊酯含量显著高于木箱（棺材）包装犬;木箱（棺材）心脏、肺脏、脑、胃及右后肢肌中氰戊菊酯含量显著高于编织袋包装犬。表明编织袋组药物分解最快,棺材次之、塑料袋最慢。2.4埋葬温度（季节）对拟除虫菊酯类农药在埋葬犬体内分解动力学的影响结果显示:甲氰菊酯实验组:3月⁶月埋葬犬尸体中肝、脾、脑、胸肌和右前肢肌甲氰菊酯含量显著高于8月¹1月埋葬犬,其它脏器组织无明显差异;氯氰菊酯实验组:4月⁷月埋葬犬尸体中心、肺、肾、脑、胃、右前肢肌和右后肢肌中氯氰菊酯含量高于8月¹1月埋葬犬;氰戊菊酯实验组:4月⁷月埋葬犬尸体中心、肝、脾、肾、脑、胃、胸肌、右前肢肌和右后肢肌氰戊菊酯含量高于8月¹1月埋葬犬。8月¹1月犬尸体腐败程度明显比3⁶月和4月⁷月埋葬犬严重,且从平均气温讲,3月⁶月和4月⁷月要低于8月¹1月。结论1.建立的甲氰菊酯、氯氰菊酯和氰戊菊酯法医毒物动力学（保存检材中分解动力学和埋藏尸体中分解动力学）研究（动物）模型,可应用于甲氰菊酯、氯氰菊酯和氰戊菊酯中毒案件法医学鉴定和法医毒物动力学的实验研究。2.改进了生物检材中甲氰菊酯、氯氰菊酯和氰戊菊酯的GC-ECD和GC/MS检测方法,该法简便、灵敏、重现性好,可应用于甲氰菊酯、氯氰菊酯和氰戊菊酯中毒死亡的法医学检验。3.甲氰菊酯、氯氰菊酯和氰戊菊酯在保存犬血液和肝脏中可发生分解,只是在不同保存条件下农药分解速率不同。低温保存可以减缓甲氰菊酯、氯氰菊酯和氰戊菊酯的分解速度,使该类药物半衰期延长,在4%甲醛溶液中保存的肝脏分解速度最慢,但添加抑菌剂（1%NaF）可加速血中拟除虫菊酯类农药的分解速度。拟除虫菊酯类农药中毒（死）案件的法医学鉴定中,所取检材应尽快送检和检测,如不能及时送检时,应低温保存,或固体检材放置于4%甲醛溶液中保存,但液体检材中不可添加NaF作为防腐剂。4.甲氰菊酯、氯氰菊酯和氰戊菊酯在不同保存条件保存血和肝中分解符合一级动力学过程二室或一室开放模式,可用C_t=A^*e^-αt+B^*e^-βt（C_t为时间t测得的含量;t表示时间,单位:d;α为第一快速分解相一级分解速率常数,β为第二慢速分解相一级分解速率常数）和C_t=C₀e^-αt表示（C_t为时间t测得的含量;t表示时间,单位:d;α为分解相一级分解速率常数,C₀为初始浓度）表示。在甲氰菊酯、氯氰菊酯和氰戊菊酯中毒（死）案件法医学鉴定时,可采用公式和分解动力学参数推断死亡当时检材内农药浓度或送检当时检材中该农药的浓度,为甲氰菊酯、氯氰菊酯和氰戊菊酯中毒（死）案件法医学鉴定提供科学依据。5.甲氰菊酯、氯氰菊酯和氰戊菊酯灌胃致死犬埋葬尸体各脏器药物含量均呈先上升后下降的趋势。甲氰菊酯、氯氰菊酯和氰戊菊酯分别在埋葬503d、480d和470d后,各组织及脏器中均可检测出该农药;染毒剂量越大的埋葬犬尸体中各脏器中含量明显高于低剂量染毒埋葬犬中的脏器药物含量;埋葬方式对埋葬犬体内甲氰菊酯、氯氰菊酯和氰戊菊酯分解速度均有影响,编织袋埋葬方式组分解最快,棺材组次之、塑料袋最慢;埋葬季节对埋葬犬体内的拟除虫菊酯类农药分解速度也有影响,气温低的季节该类农药在埋葬犬体内分解速度明显低于温度高的季节。6.甲氰菊酯、氯氰菊酯和氰戊菊酯中毒（死）埋葬尸体法医学鉴定时,应根据埋葬时间、服毒剂量、埋葬方式和埋葬季节等对尸体中拟除虫菊酯类农药分解的影响,结合服毒方式和生前抢救情况,综合判断尸体挖掘的价值和可能性,并及早进行尸体挖掘和检测,全面取材进行毒物分析,并可根据其分解规律,充分考虑偶发因素的影响,大致推断中毒致死时尸体内甲氰菊酯、氯氰菊酯和氰戊菊酯的浓度。更多还原

【Abstract】 Objictive1. To develop decomposition kinetics model of pyrethriod insecticides in preserved specimens and buried cadaver of dogs.2. To improve a GC equipped with an ECD and a GC/MS analysis for pyrethriod insecticides determination.3. To investigate the decomposition kinetics of pyrethriod insecticides in preserved specimens and buried cadaver of dogs.Methods1.The decomposition kinetics in preserved samples1.1 Group: Eighteen dogs were allocated into three groups randomly.The first group（sixe dogs） was given an intragastric administration of fenpropathrin with a dose of 8LD₅₀; The second group （sixe dogs） was given an intragastric administration of cypermethrin with a dose of 10LD₅₀; The third group（sixe dogs） was given an intragastric administration of fenvalerate with a dose of 10LD₅₀.1.2 The study on decomposition kinetics: The dogs were dissected as soon as their vital signs disappeared after intoxication. The blood and liver of every dog were divided into four parts. Three of them were preserved at -20℃, 4℃, 20℃respectively;another blood containing 1%NaF or liver fixed with 4% formaldehyde solution were preserved at 20℃. Fenpropathrin, cypermethrin and fenvalerate were determined by the GC equipped with an ECD and a GC/MS on different days after the storage. The equation and parameters of decomposition kinetics were imitated and calculated with WinNonlin program.2. Study on the decomposition kinetics of fenpropathrin cypermethrin fenvalerate in buried cadavers2.1 The effection of time to the decomposition kinetics in buried cadavers.2.1.1 Group: Ninety-nine dogs were allocated into three groups randomly.The first group （Thirty-three dogs） was given an intragastric administration of fenpropathrin with a dose of 8LD₅₀; The second group （Thirty-three dogs） was given an intragastric administration of cyper- methrin with a dose of 10LD₅₀; The third group（Thirty-three dogs） was given an intragastric ad- ministration of fenvalerate with a dose of 10LD₅₀.2.1.2 Study on the decomposition kinetics of buried cadavers: The dogs were put into unsealed plastic bags after the death, buried in the hollow （100 cm 100 cm 150cm）. On 0d,35d,65d,95d,125d,200d,383d and 503d after the burial ,three of the first group dogs were dugged out and dissected, the specimens were collected for fenpropathrin analysis by a GC-ECD and GC/MS. On 0d, 30d, 60d, 90d, 210d, 360d and 480d after the burial, three of the second group dogs were dugged out and dissected, the specimens were collected for cypermethrin analysis by a GC-ECD and GC/MS. On 0d, 30d, 52d, 82d, 200d, 350d and 470d, after the burial, three of the third group dogs were dugged out and dissected, the specimens were collected for fenvalerate analysis by a GC-ECD and GC/MS.2.2 The effection of doses on the decomposition kinetics in buried cadavers.2.2.1 Group: Eighteen dogs were allocated into three groups randomly. The first group（six dogs） was given an intragastric administration of fenpropathrin with the doses of 4LD₅₀ and 8LD₅₀; there were three dogs in each dose group. The second group （six dogs） was given an intragastric administration of cypermethrin with the doses of 2LD₅₀ and 10LD₅₀; there were three dogs in each dose group. The third group（six dogs） was given an intragastric administration of fenvalerate with the doses of 2LD₅₀ and 10LD₅₀; there were three dogs in each dose group.2.2.2 Study on the decomposition kinetics of buried cadavers: The dogs were put into semi-sealed plastic bags after the death, buried in the pits（100 cm 100 cm 150cm）. On 60d after the burial, the dogs were dugged out, dissected, and the specimens were collected for fenpropathrin, cypermethrin or fenvalerate cypermethrin analysis by a GC-ECD and GC/MS.2.3 The effection of burial way on the decomposition kinetics in buried cadavers.2.3.1 Group: Twenty-seven dogs were allocated into three groups randomly. The first group （nine dogs） was given an intragastric administration of fenpropathrin with a dose of 8LD₅₀; the second group （nine dogs） was given an intragastric administration of cypermethrin with a dose of 10LD₅₀; the third group（nine dogs） was given an intragastric administration of fenvalerate with a dose of 10LD₅₀.2.3.2 The dogs were put into semi-sealed plastic bags, woven bags and wooden cases （coffins） respectively after the death, buried in the pits（100 cm 100 cm 150cm）. On 60d after the burial, the dogs were dugged out, dissected, and the specimens were collected for fenpropathrin, cypermethrin or fenvalerate cypermethrin analysis by a GC-ECD and GC/MS.2.4 The effection of temprerature on the decomposition kinetics in buried cadavers.2.4.1 Group: Eighteen dogs were allocated into three groups randomly. The first group（six dogs） was given an intragastric administration of fenpropathrin with a dose of 8LD₅₀. The second group （six dogs） was given an intragastric administration of cypermethrin with a dose of 10LD₅₀; the third group（six dogs） was given an intragastric administration of fenvalerate with a dose of 10LD₅₀.2.4.2 Study on the decomposition kinetics of buried cadavers: The dogs were put into semi-sealed plastic bags after the death, buried in the pits （100 cm×100 cm×150cm）. For the fir st group, three dogs were buried on 09/3/21 and dugged out on 09/6/6（75days）, the other three dogs were buried on 09/8/24 and dugged out on 09/11/8. For the second group, three dogs were buried them on 09/4/11 and dugged out on 09/6/25（75days）, the other three dogs were buried on 09/8/24 and dugged out on 09/11/8. For the third group, three dogs were buried on 09/4/11 and dugged out on 09/6/25（after 75days）, the other three dogs were buried on 09/8/24 and dugged out on 09/11/8. The dogs were dissected, and the specimens were collected for fenpropathrin, cypermethrin or fenvalerate cypermethrin analysis by a GC-ECD and GC/MS.Results1. The decomposition kinetics of pyrethriod insecticides in preserving specimen1.1 Fenpropathrin:The decomposition kinetics of fenpropathrin in preserved blood and liver fit to the first-order kinetic process.The common equation were C_t=A^*e^-αt+B^*e^-βt and C_t=C₀e^-αt. Compared with the 0 d, the content of fenpropathrin in preserved blood and liver at-20℃descended significantly to 82.6±15.2% and 98.2±37.6% on 13 d. The fenpropathrin could not be detected in blood preserved at -20℃on the 215^th d, but the content of fenpropathrin in liver preserved at -20℃descended to 14.7 9.2%. The decomposition half-life of fenpropathrin in blood and liver at -20℃were 18.07days and 40.57days respectively; Compared with the 0d, the content of fenpropathrin in blood and liver preserved at 4℃descended significantly to 66.326.1% and 79.1 31.2% on 13 d; the fenpropathrin could not be detected in blood preserved at 4℃on 185 d, but the content of fenpropathrin in liver preserved at 4℃descended to 0.90.9% on 345 d; the decomposition half-life of fenpropathrin in blood and liver preserved at 4℃were 15.74 d and 33.90d. Compared with the 0 d, the content of fenpropathrin in blood and liver preserved at 20℃descended significantly to 63.0±28.3% and 85.3 32.1% on 13 d. The fenpropathrincould not be detected in blood and liver preserved at 20℃on 185 d and 345 d respectively. The decomposition half-life of fenpropathrin in blood and liver preserved at 20℃were 13.99days and 23.68days respectively; Compared with the 0 d, the content of fenpropathrin in blood preserved at 20℃and containing 1%NaF descended significantly to 59.8 21.7% on 13d, it could not be detected on 155 d, the half-life of fenpropathrin in blood preserved at 20℃and containing 1%NaF was 9.94days; the content of fenpropathrin in liver stored at 20℃（fixed with 4% formaldehyde） descended to 94.5 23.9% on 13 d, the half-life was 51.97days.1.2 Cypermethrin: The decomposition kinetics of cypermethrin in preserved blood and liver fit to the first-order kinetic process.The common equation were C_t=A^*e^-αt+B^*e^-βt and C_t=C₀e^-αt. Compared with the 0 d, the content of cypermethrin in blood and liver preserved at-20℃descended significantly to 64.4±2.8% and 91.1±2.9% on 40d, 42.0 2.9% and 76.45.8% on 290d, the decomposition half-life were 182.83 days and 826.01days respectively; Compared with the 0d, the content of cypermethrin in blood and liver preserved at 4℃ descended significantly to 54.3±1.4% and 79.4±5.8% on 40 d, 26.1 10.9% and 50.0 20.5% on 290d, the decomposition half-life were 93.76 days and 327.18 days respectively. Compared with the 0d, the content of cypermethrin in blood and liver preserved at 20℃descended significantly to 27.5±3.6% and 70.5±2.9% on 40d, the content of cypermethrin in preserved blood descended to 11.5 1.4% on 290d, the decomposition half-life of cypermethrin in blood preserved at 20℃was 10.54 days; Compared with the 0d, the content of cypermethrin in blood containing 1% NaF and liver fixed with formaldehyde preserve at 20℃descended significantly to 25.3±0.7% and 91.1±2.9% on 40d, 10.8±0.7% and 91.1±2.9% on 290d, the decomposition half-lifes were 5.11 days and 2288.49 days respectively.1.3 Fenvalerate: The decomposition kinetics of fenvalerate in preserved blood and liver fit to the first-order kinetic process.The common equation were C_t=A^*e^-αt+B^*e^-βt and C_t=C₀e^-αt. Compared with the 0d, the content of fenvalerate in blood and liver preserved at-20℃descended significantly to 73.6±0.5% and 95.6±8.6% on 40d, 29.6 4.0% and 50.2 4.3% on 290d, the decomposition half-lifes were 110.08 days and 347.14days; Compared with the 0d, the content of fenvalerate in blood and liver preserved at 4℃descended significantly to 26.4±6.4% and 78.3±13.0% on 40d, 6.4 0.8% and 30.4 4.3% on 290d, the decomposition half-lifes were 36.84 days and 226.42days. Compared with the 0d, the content of fenvalerate in blood and liver preserved at 20℃descended significantly to 33.7±1.1% and 47.8±4.3% on 40d; the content of fenvalerate in preserved blood descended to 6.5 0.8% on 290d; the decomposition half-lifes of fenvalerate in blood preserved at 20℃was 24.00 days; Compared with the 0d, the content of fenvalerate in blood（1% NaF） and liver（fixed with formaldehyde） preserved at 20℃descended significantly to 2.4 1.6% and 104.3 4.3% on 40d; fenvalerate could not be detected out in blood （1%NaF） preserved at 20℃on 228d, but the content of fenvalerate in liver preserved at 20℃（fixed with formaldehyde） only descended significantly to 86.9 4.3% on 290d; the decomposition half-lifes of fenvalerate in blood（1% NaF） and liver（fixed with formaldehyde） preserved at 20℃were 6.18 days and 763.75 days respectively.2.Decomposition kinetics of in pyrethriod in buried cadavers of dogs2.1 The effection of time on the decomposition kinetics in buried cadavers:Fenpropathrin group:Decomposition kinetics of fenpropathrin in buried cadavers of dogs which died from an intragastric administration of 8LD₅₀. The fenpropathrin content in heart, spleen,lung,kidney, brain,pectoralis muscles, muscle of the right anterior limb,muscle of the right posterior limb reduced gradually to 17.6%-71.1% of the 0 d after it rised to the peak on 95 d. While the gastric wall and liver had a rise trends until the 383d. Cypermethrin group: Decomposition kinetics of in cypermethrin in buried cadavers of dogs which died from an intragastric administration of 10LD₅₀. The cypermethrin content of heart ,spleen ,lung ,kidney ,brain ,gastric wall reduced gradually after it rised to the peak on 60d.While the pectoralis muscles and muscle of the right posterior limb rised to the peak point on 210d.Then the cypermethrin content of the samples reduced gradually. Fenvalerate group: Decomposition kinetics of in fenvalerate in buried cadavers of dogs which died from an intragastric administration of 10LD₅₀. The fenvalerate content in heart、liver、kindy reduced gradually after it rised to the peak point on 350d. The fenvalerate content in brain and gastric wall rised to the peak point on 52 d.2.2 The effection of doses to the decomposition kinetics in buried cadavers: The results of the three experimental groups（fenpropathrin,cypermethrin,fenvalerate） showned that the drug content of the high dose group was higher than the low dose group in the heart,liver,kindy,brain and gastric wall .But the drug content in muscles had no significant difference between the two dose groups.2.3 The effection of burial way to the decomposition kinetics in buried cadavers: The experimental group of fenpropathrin showed that the fenpropathrin content, detected in the heart, lung, brain and gastric wall, was higher in plastic bags than those in wooden box after 75 days. The fenpropathrin content, detected in the heart, liver, spleen,brain, muscle of the right anterior limb and muscle of the right posterior limb, was higher in the wooden box than those in woven bag; Cypermethrin group: the cypermethrin content, detected in the heart,liver, lung, brain and gastric wall, was higher in plastic bags than those in wooden box after 75 days. The cypermethrin content, detected in the heart, liver, lung, gastric wall, muscle of the right anterior limb and muscle of the right posterior limb,was higher in in the wooden box than those in woven bag; Fenvalerate group: The fenvalerate content, detected in the heart, brain, muscle of the right anterior limb and muscle of the right posterior limb, was higher in plastic bags than those in wooden box after 75 days. The fenvalerate content, detected in the heart, lung, brain, gastric wall and muscle of the right posterior limb, was higher in the wooden box than those in woven bag.2.4 The effection of temperature to the decomposition kinetics in buried cadavers: The fenpropathrin group: The content of fenpropathrin, detected in the liver,spleen,brain, chest muscle and muscle of the right posterior limb, was higher buried in March to June than those buried in August to November.The other samples had no significant difference. The cypermethrin group: The content of cypermethrin, detected in heart,lung,kindy,spleen,brain and muscle of the right posterior limb, was higher buried in April to July than those buried in August to November. The fenvalerate group: The content of fenvalerate, detected in heart,liver,kindy,spl- een,brain,breast muscle and muscle of the right posterior limb, was higher buried in April to July than those buried in August to November.The rot leave of the dog remains which buried in August to November was more seriously than those in April to July. The average temperature in April to July and March to June is lower than August to November. Conclusion1. The dogs decomposition kinetics model of fenpropathrin, cypermethrin and fenvalerate have been developed, which can be applied to forensic identification, study on forensic toxicokinetics.2. The improved GC-ECD and GC-MS methods can be used in the forensic identification and forensic toxic kinetics study on fenpropathrin, cypermethrin and fenvalerate poisoning death.3. Fenpropathrin, cypermethrin and fenvalerate in specimens were found to be decomposed at various kinds preserved environment. Cryopreservation and formaldehyde can slow down the decomposition of the pyrethroids insecticides; But the NaF can speed up the decomposition.We suggest that the specimens for analysis should be submitted as soon as possible, NaF should not be added into the samples.4. The decomposition kinetics of fenpropathrin, cypermethrin and fenvalerate in blood and liver fit to the first-order kinetic process. The common equation was C_t=A^*e^-αt+B^*e^-βt and C_t=C₀e^-αt, which could be used to conclude the concentrations of fenpropathrin, cypermethrin and fenvalerate when the specimen were collected.5. The content of fenpropathrin, cypermethrin and fenvalerate in the samples of buried dogs showed a firstly increase and a next decrease. The fenpropathrin, cypermethrin and fenvalerat could be detected on 503 days, 480 days and 470 days after the bural. The decomposition kinetics of fenpropathrin, cypermethrin and fenvalerate in buried dogs showed a dose, burial ways and temperature dependent.6. In the forensic identification of buried cadavers of fenpropathrin, cypermethrin and fenvalerate poisoning death, we shoud take the whole situations into the consideration, which include buried time, buried way and buried seasons, and so on. Cadaver-dugging and toxic analysis should be carried out as soon as possible.更多还原