敌百虫对斑点叉尾鮰的急性毒性试验

[目的]了解敌百虫对斑点叉尾鮰的急性毒性情况。[方法]以健康斑点叉尾鮰鱼种为试材,平均体重46.7 g,敌百虫设6个浓度梯度(0.1、0.4、0.8、1.2、2.4和3.2 mg/L),在室内常温静水条件下,对斑点叉尾鮰进行急性毒性正交试验。[结果]敌百虫对斑点叉尾鮰的24、48、72、96 h的半致死浓度分别为1.6、1.1、0.8、0.7 mg/L;安全浓度0.07 mg/L。敌百虫毒性强,使用时必须等毒性消失后才能放鱼苗;不同鱼类对敌百虫敏感性有差异很大,斑点叉尾鮰对敌百虫非常敏感,浓度为0.8 mg/L时已有将近50%的鱼死亡,而未死亡的鱼也表现出不同的中毒症状;大剂量使用不仅会出现残留、阻碍鱼类生长,而且还会污染水质。[结论]建议生产上敌百虫与其他药物轮用,使用时须等毒性消失后使用。

Acute Toxicity Test of Trichlorphon on Ictalurus punctatus

[Objective] The purpose was to learn about the acute toxicity of trichlorphon to Ictalurus punctatus.[Method] With healthy I.Punctatus fingerlings with mean body weight of 46.7 g as tested materials, in indoor static water at normal temperature, 6 concn.(0.1, 0.4, 0.8, 1.2, 2.4 and 3.2 mg/L) of trichlorphon were designed for performing orthogonal experiment of acute toxicity on I.Punctatus.[Result] The median lethal concn.of trichlorphon on I.punctatus in 24, 48, 72 and 96 h were 1.6, 1.1, 0.8 and 0.7 mg/L resp.and its safe concn.was 0.07 mg/L.The trichlorphon was heavy-toxicity and when it was applied, the fry could not be put into the water until its toxicity was eliminated.The sensitivities of different fishes to trichlorphon had great difference.The I.punctatus was very sensitive to trichlorphon and when its concn.was 0.8 mg/L, there had been about 50% of fish died and the survival showed different toxic symptom.Its large dosage not only produced residues and inhibited the growth of fishes, but also contaminated water quality.[Conclusion] It was suggested that trichlorphon should be used rotationally with the other insecticides in production, and the later could not be applied until the toxicity of the former was eliminated.