The Reserch Of Carbaryl And The Degration Product1-Naphthol On Estrogen Effect In Male Tilapia

Carbaryl is a kind of pesticide, which are used widely.1-Naphthol is the degradated product of carbaryl which are used widely,too.They can go into the water-bodies by the ways of surface water runoff,eluviation,dry or wet sedimentations,and produce toxicological effects on aquatic animals at the same time.These days,a great deal of attention has focused on carbaryl for its large use.The experiments used the male Tilapia as test animal, then researched acute toxicity of carbaryl and1-naphthol to male Tilapias and effects of low concentration of carbaryl,1-naphthol on serum estradiol content, testosterone, vitellogenin, and gonadal maturation coefficient.The results as follows:The result of the acute toxicity:24h,48h,72h and96h LC50of carbaryl to Tilapia were30.21mg/L,25.16mg/L,19.76mg/L,17.86mg/L,respectively. So the safety concentration of carbary to Tilapia was1.79mg/L.The24h,48h,72h and96h LC50of1-naphthol to Tilapia were7.46mg/L,7.21mg/L,6.71mg/L,6.39mg/L, respectively.So the safety concentration of1-naphthol to Tilapia was0.639mg/L. Consequently,carbaryl was low toxic to Tilapia.1-naphthol was middle toxic to Tilapia.After30days of continuous exposure of carbaryl and1-Naphthol,we determined the gonadal maturation coefficient in male Tilapia.The results showed:when the concentration of carbaryl was0.8mg/L,5mg/L,the gonadal maturation coefficient was lower than the control.When the concentration of1-Naphthol was2mg/L, the gonadal maturation coefficient began to reduce.Beacause the carbaryl and1-naphthol are insoluble in water,we make the acetone as solubilizer.In the experiment,we examined whether acerone can effect the endocrine. We found that the concentration of serum estradiol, testosterone in male Tilapia exposed to actone were similar with control.And we can not detect vitellogenin in the serum of male Tipia exposed to acetone. After30days of continuous exposure,we found that when the concentration of carbaryl was0.16mg/L,0.8mg/L,2mg/L,5mg/L,the concerntration of serum estradiol was higher than control(p<0.05).When the concerntration of carbaryl was0.8mg/L,the quantity of serum estradiol was the most.To the male Tilapia exposed to1-naphthol,only when the concentration of1-naphthol was2mg/L,it can effect the concentration of serum estradiol significantly.Then, we researched the concerntration of serum estradiol in male Tilapia at2mg/L carbaryl and2mg/L1-naphthol in different days(3d,14d,23d,30d).To the Tilapia exposed the2mg/L carbary,the concen-tration of serum estradiol increased at23d and30d significantly.At23d,the quantity reached the most compaired with others.To the Tilapia exposed to the2mg/L1-naphthol,the concentration of serum estradiol increased and significantly higher than control(p<0.05).After30days of continuous exposure,we found when the concentration of carbaryl was0.16mg/L,2mg/L.the testosterone was lower than the control.when it was2mg/L,the concentration of testosterone was the lowest.reducing about27%compaired with control.When the concentration of1-naphthol was0.8mg/L,2mg/L,the concentration of testosterone can reduce.The more1-naphthol was,the lower concentration of testosterone was. After14days of continues exposure in2mg/L carbary,the concentration of testosterone began to reduce.At30day,the concentration of testosterone was the lowest(p<0.01).And the concentration of testosterone decreased and significantly lower than control (p<0.05) at30day of exposed to2mg/L1-naphthol.From the results,we can find that the effect of carbaryl is more significant than1-naphthol about the testosterone.In the experiment,we measured the concentration of vitellogenin in male Tilapia exposed to carbaryl and1-naphthol.The resuts showed:in the1-naphthol,we can not find the vitellogenin.To the Tipia exposed to carbaryl,we can find the vitellogenin in5mg/1carbaryl..In order to determine if the cancaryl have the estrogen effect,we exposed the Tilapia in1mg/L carbaryl,4mg/L carbaryl,10μg/L17β-E2,100μg/117β-E2. The result showed that carbaryl and17P-E2can make the serum estradiol increase in male Tipia,and make the vitellogenin produced.But the effect of17β-E2is stronger than the carbaryl.