Studies On The Effects Of Carbofuran Methylparathion On Xiangyunji Brain AchE

Studies on the Effects of CarbofuranMethylparathion on Xiangyunji Brain AchEAbstractIn this dissertation. the acute toxicity of carbofuran, methylparation and theirmixed toxicity on Xiangyunji were studied, meanwhile the effects of carbofuran,methylparation and their mixturc on the inhibition and recovery of the activity ofXiangyunji brain AchE as well as their mechanism were investigated. The mainresults were as fOllows'At the water temperature of 23i l C,the 96 hours LC5o of carbofuran toXiangyunji was l .l5mg/l, and that of methylparathion to Xiangyunji was 8.5lmg/l.Accooding to "Regulations for environmental satbty evaluation experiment ofchemical pesticides" issued in China, both of the pesticides were medium toXiangyunji. According to Symth methods, the interaction between the two pesticideswas addition.The inhibition rate of 0.25mg/l carbofuran on Xiangyunji brain AchE reached amaximum(30.9%) after 24 hours treatment, then decreased with time. The inhibitionrate of 2.0mg/l methylparathion on Xiangyunji brain AchE increased with time. andreached a maximum(39.4%) after 96 hours treatment. Similarly, the AchE inhibitionrate in mixture treatment increased with time, and reached a maximum(45.4%) at theend of the experiments(96 hours).The inhibited AchE in Xiangyunji which had been treated with 0.25mg/lcarbotliran for 48 hours recovered soon. After Xiangyunji had been transtbrred intoclean water fOr 96 hours, the inhibited AchE almost recovered completely. However,the inhibited AchE in Xiangyunji which had been treated with 2.0mg/lmethylparathion for 48 hours recovered slowly, and the AchE inhibition rate reached20.l% after Xiangyunji had been being transferred into clean water for 96 hours.Xiangyunji having been treated with mixed 0.25mg/l carbotliran and 2.0mg/lmethylparathion for 48 hours, the recovery of the inhibited AchE was the mostdifficult. Even Xiangyunji had been transferred into clean water for 96 hours, theAchE inhibition rate reached 3l .6%.The experimental results of the two pesticides on Xiangyunji brain AchE in vitroshowed that at certain concentrations, the AchE activity was of postive relevance tothe treatment concentrations of the pesticides. The results also showed theconcentrations of carbofuran, methylparathion required to affect 50% inhibition ofXiangyunji brain AchE were 1.1 8mg/I and 8.26mg/I respectively, which certified the effects in vitro could be used as an index of toxicological assessment.AuthorLin Qintie (Environmental Science and Engineering)Directed by Professor Yang Renbin...