两种不同剂型毒死蜱对四种环境生物的毒性评价

按照化学农药环境安全评价试验准则方法,测定了40%毒死蜱乳油和30%毒死蜱微囊悬浮剂对鱼类、鸟类、家蚕和蜜蜂4种环境生物的毒性。结果表明,毒死蜱乳油对斑马鱼LC50值（96 h）为0.68 mg.L^-1,毒死蜱微囊悬浮剂的LC50为47.30 mg.L^-1;毒死蜱乳油对鹌鹑的毒性LD50为7.45 mg.kg^-1,毒死蜱微囊悬浮剂的LD50为56.97 mg.kg^-1。食下毒叶法结果表明,毒死蜱乳油对2-4龄家蚕幼虫LC50值（48 h,25℃）分别为0.82、1.87 mg.L^-1与4.35 mg.L^-1,毒死蜱微囊悬浮剂为2.48、4.22 mg.L-1与8.35 mg.L^-1;家蚕幼虫在药膜上爬行1、10、30 min与60 min后,毒死蜱乳油对3龄家蚕幼虫的LD50值（48 h,25℃）分别为3.18、0.68、0.41μg.cm^-2与0.38μg.cm^-2,其微囊悬浮剂LD50值分别为6.92、1.58、1.18μg.cm^-2与0.48μg.cm^-2;毒死蜱乳油和微囊悬浮剂对蜜蜂48 h的LC50分别为0.53 mg.L^-1和2.32 mg.L^-1。上述结果表明,毒死蜱微囊悬浮剂对4种环境生物的安全性明显高于乳油。

Toxicity Assessment of Two Different Formulations of Chlorpyrifos to Four Environmental Organisms

The toxicities of two different formulations of chlorpyrifos,emulsifiable concentrate（EC）and capsule suspension（CS）,to 4 species of environmental organisms were evaluated,according to the commendatory general method named Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticide.The results indicated that LC5（096 h）of chlorpyrifos EC to zebra fish（Brachydanio rerio）was 0.68 mg.L-1 and another formulation of the insecticide,chlorpyrifos CS was 47.30 mg.L-1,respectively.The results also showed that the LD50 of chlorpyrifos EC to quail（Coturnix japonica）was 7.45 mg.kg-1,but the different formulation of chlorpyrifos CS to the same tested bird was 56.97 mg.kg-1.Meanwhile,the toxicities of the different insecticide formulations to silkworm（Bombyx mori L.）were evaluated in the laboratory using the leaf dipping method.The results indicated that the LC50（48 h,25 ℃）of chlorpyrifos EC to silkworm was 0.82,1.87 mg.L-1 and 4.35 mg.L-1 for the second,third and fourth-instar,respectively but the LC5（048 h,25 ℃）of another formulation,chlor-pyrifos CS to the tested animal was 2.48,4.22 mg.L-1 and 8.35 mg.L-1,respectively.After contact of silkworm with filter paper treated by chlorpyrifos in time of 1,10,30 min and 60 min,the LD50（48 h,25 ℃）of chlorpyrifos EC to third-instar larvae was 3.18,0.68,0.41,0.38 μg.cm-2 and the LD5（048 h,25 ℃）of chlorpyrifos CS to silkworm was 6.92,1.58,1.18,0.48 μg.cm-2,respectively.The results also indicated that the LC5（048 h）to bee（Apis mellifera L.）of chlorpyrifos EC or chlorpyrifos CS was 0.53 mg.L-1 or 2.32 mg.L-1,respectively.The results indicated that safety of chlorpyrifos CS to 4 species of environmental organisms was obviously higher than that of chlorpyrifos EC.