双酚A对中国林蛙蝌蚪生长发育的毒性效应

为评价双酚A(BPA)对中国林蛙(Rana chensinensis)蝌蚪的急性毒性,将26期的蝌蚪暴露于浓度为2.4×10-5mol·L-1～4.2×10-5mol·L-1BPA的水体中进行急性毒性实验.结果表明,24、48、72、96h蝌蚪的死亡几率(y)与浓度对数(x)的回归方程分别为y=16.915x-4.1157、y=22.11x-6.1905、y=20.766x-5.3871、y=20.715x-5.351;半数致死浓度(LC50)分别为3.47×10-5、3.28×10-5、3.20×10-5、3.16×10-5mol·L-1.安全浓度(SC)为0.88×10-5mol·L-1.为探讨在安全浓度以下BPA对中国林蛙蝌蚪生长发育的影响,将林蛙蝌蚪分别于10-5、10-6、10-7mol·L-1BPA的水体中连续暴露直至完全变态,并设10-8、10-9mol·L-1雌二醇(E2)的阳性对照和空白对照,分别测定并统计蝌蚪发育所需的发育时间、体长和体质量.结果表明,蝌蚪对10-5、10-6、10-7mol·L-1BPA与10-8、10-9mol·L-1E2的效应相似,可延缓林蛙幼体的发育时间,导致体长和体质量降低.推测低浓度BPA抑制蝌蚪生长发育的机制之一是干扰了正常的内分泌活动.

Toxicity Effects of Bisphenol A on Growth and Development of Rana chensinensis Tadpoles

A standard method was used to evaluate the acute toxicity of Bisphenol A(BPA)on Rana chensinensis tadpoles at stage 26.Results showed that the regression equation between the death probability(y)and the logarithm of BPA concentration(x)were y=16.915x-4.1157,y=22.11x-6.1905,y=20.766x-5.3871 and y=20.715x-5.351 for 24,48,72 and 96h,respectively,with mean LC50 values were 3.47×10-5,3.28×10-5,3.20×10-5 and 3.16×10-5mol·L-1,respectively.The safe concentration(SC)was 0.88 ×10-5mol·L-1.In order to examine the effects of lower concentration BPA on the growth and development of R.chensinensis tadpoles,the individuals were continuously exposed to 10-5,10-6,10-7 mol·L-1 of BPA till metamorphosis,with 10-8,10-9mol·L-1 of E2 as positive control.The duration of metamorphosis,body length and weight were determined at different stages,respectively.Results showed that BPA had the similar effect of E2.BPA could delay the time of development,and decrease the body length and weight.It was speculated that BPA could suppressed growth and development of tadpoles through disturbing endocrine activity.